diff --git a/.github/workflows/golangci-lint.yml b/.github/workflows/golangci-lint.yml
index 927ae79a..768ceb4e 100644
--- a/.github/workflows/golangci-lint.yml
+++ b/.github/workflows/golangci-lint.yml
@@ -4,18 +4,21 @@ on:
     branches:
     - master
   pull_request:
+
 permissions:
   contents: read
+
 jobs:
   golangci:
     name: lint
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-22.04
     steps:
-      - uses: actions/setup-go@v3
+      - uses: actions/setup-go@v5
         with:
-          go-version: '^1.20'
-      - uses: actions/checkout@v3
+          cache: false
+          go-version: '1.20'
+      - uses: actions/checkout@v4
       - name: golangci-lint
-        uses: golangci/golangci-lint-action@v3
+        uses: golangci/golangci-lint-action@v4
         with:
-          version: latest
+          args: --timeout=60m
diff --git a/.github/workflows/revive.yml b/.github/workflows/revive.yml
new file mode 100644
index 00000000..60ef0b3a
--- /dev/null
+++ b/.github/workflows/revive.yml
@@ -0,0 +1,20 @@
+name: revive
+on:
+  push:
+    branches:
+    - master
+  pull_request:
+
+permissions:
+  contents: read
+
+jobs:
+  revive:
+    runs-on: ubuntu-22.04
+    steps:
+      - uses: actions/setup-go@v5
+        with:
+          cache: false
+          go-version: '1.20'
+      - uses: actions/checkout@v4
+      - uses: morphy2k/revive-action@v2
diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index 1d6983cc..4eafaa96 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -6,12 +6,14 @@ on:
   pull_request:
 jobs:
   test:
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-22.04
     steps:
-      - uses: actions/setup-go@v3
+      - uses: actions/setup-go@v5
         with:
-          go-version: '^1.20'
-      - uses: actions/checkout@v3
-      - uses: n8maninger/action-golang-test@v1
+          cache: false
+          go-version: '1.20'
+      - uses: actions/checkout@v4
+      - uses: n8maninger/action-golang-test@v2
         with:
           args: "-race;-timeout=30m"
+
diff --git a/.golangci.yml b/.golangci.yml
index b896e60e..30a8a1c8 100644
--- a/.golangci.yml
+++ b/.golangci.yml
@@ -109,6 +109,56 @@ linters-settings:
   lll:
     line-length: 132
 
+  revive:
+    ignore-generated-header: true
+    severity: error
+    confidence: 0.1
+    errorCode: 0
+    warningCode: 0
+    rules:
+      - name: atomic
+      - name: blank-imports
+      - name: comment-spacings
+      - name: confusing-results
+      - name: constant-logical-expr
+      - name: context-as-argument
+      - name: context-keys-type
+      - name: datarace
+      - name: defer
+      - name: dot-imports
+      - name: duplicated-imports
+      - name: early-return
+      - name: error-strings
+      - name: errorf
+      - name: exported
+      - name: file-header
+      - name: identical-branches
+      - name: import-alias-naming
+      - name: import-shadowing
+      - name: increment-decrement
+      - name: indent-error-flow
+      - name: modifies-value-receiver
+      - name: range-val-address
+      - name: range-val-in-closure
+      - name: range
+      - name: receiver-naming
+      - name: string-of-int
+      - name: superfluous-else
+      - name: time-equal
+      - name: time-naming
+      - name: unchecked-type-assertion
+      - name: unhandled-error
+        arguments:
+          - "fmt.Fprint"
+          - "fmt.Fprintf"
+      - name: unnecessary-stmt
+      - name: unused-parameter
+      - name: unused-receiver
+      - name: use-any
+      - name: useless-break
+      - name: var-naming
+      - name: waitgroup-by-value
+
   stylecheck:
     checks: [ "all", "-ST1000" ]
 
diff --git a/api/submitblindedproposalopts.go b/api/submitblindedproposalopts.go
index 8355f47d..4edb2f3c 100644
--- a/api/submitblindedproposalopts.go
+++ b/api/submitblindedproposalopts.go
@@ -13,7 +13,7 @@
 
 package api
 
-import v2 "github.com/attestantio/go-eth2-client/api/v2"
+import apiv2 "github.com/attestantio/go-eth2-client/api/v2"
 
 // SubmitBlindedProposalOpts are the options for submitting proposals.
 type SubmitBlindedProposalOpts struct {
@@ -23,5 +23,5 @@ type SubmitBlindedProposalOpts struct {
 	Proposal *VersionedSignedBlindedProposal
 
 	// BroadcastValidation is the validation required of the consensus node before broadcasting the proposal.
-	BroadcastValidation *v2.BroadcastValidation
+	BroadcastValidation *apiv2.BroadcastValidation
 }
diff --git a/api/submitproposalopts.go b/api/submitproposalopts.go
index 48884913..fafe1984 100644
--- a/api/submitproposalopts.go
+++ b/api/submitproposalopts.go
@@ -13,7 +13,7 @@
 
 package api
 
-import v2 "github.com/attestantio/go-eth2-client/api/v2"
+import apiv2 "github.com/attestantio/go-eth2-client/api/v2"
 
 // SubmitProposalOpts are the options for submitting proposals.
 type SubmitProposalOpts struct {
@@ -23,5 +23,5 @@ type SubmitProposalOpts struct {
 	Proposal *VersionedSignedProposal
 
 	// BroadcastValidation is the validation required of the consensus node before broadcasting the proposal.
-	BroadcastValidation *v2.BroadcastValidation
+	BroadcastValidation *apiv2.BroadcastValidation
 }
diff --git a/api/v1/capella/generate.go b/api/v1/capella/generate.go
index 99ada52b..8262a319 100644
--- a/api/v1/capella/generate.go
+++ b/api/v1/capella/generate.go
@@ -16,5 +16,4 @@ package capella
 // Need to `go install github.com/ferranbt/fastssz/sszgen@latest` for this to work.
 //go:generate rm -f blindedbeaconblockbody_ssz.go blindedbeaconblock_ssz.go signedblindedbeaconblock_ssz.go
 //go:generate sszgen --include ../../../spec/phase0,../../../spec/altair,../../../spec/bellatrix,../../../spec/capella -path . --suffix ssz -objs BlindedBeaconBlockBody,BlindedBeaconBlock,SignedBlindedBeaconBlock
-//nogo:generate sszgen --include ../../../spec/phase0,../../../spec/altair,../../../spec/bellatrix,../../../spec/capella --exclude-objs=blindedBeaconBlockBodyJSON,blindedBeaconBlockBodyYAML,blindedBeaconBlockJSON,blindedBeaconBlockYAML,signedBlindedBeaconBlockJSON,signedBlindedBeaconBlockYAML -path . --suffix ssz -objs BlindedBeaconBlockBody,BlindedBeaconBlock,SignedBlindedBeaconBlock
 //go:generate goimports -w blindedbeaconblockbody_ssz.go blindedbeaconblock_ssz.go signedblindedbeaconblock_ssz.go
diff --git a/api/v1/deneb/blockcontents_yaml.go b/api/v1/deneb/blockcontents_yaml.go
index 578fae5e..356e6e90 100644
--- a/api/v1/deneb/blockcontents_yaml.go
+++ b/api/v1/deneb/blockcontents_yaml.go
@@ -46,15 +46,15 @@ func (b *BlockContents) MarshalYAML() ([]byte, error) {
 // UnmarshalYAML implements yaml.Unmarshaler.
 func (b *BlockContents) UnmarshalYAML(input []byte) error {
 	// We unmarshal to the JSON struct to save on duplicate code.
-	var data blockContentsJSON
-	if err := yaml.Unmarshal(input, &data); err != nil {
+	var unmarshaled blockContentsJSON
+	if err := yaml.Unmarshal(input, &unmarshaled); err != nil {
 		return errors.Wrap(err, "failed to unmarshal YAML")
 	}
 
-	bytes, err := json.Marshal(data)
+	marshaled, err := json.Marshal(unmarshaled)
 	if err != nil {
 		return errors.Wrap(err, "failed to marshal JSON")
 	}
 
-	return b.UnmarshalJSON(bytes)
+	return b.UnmarshalJSON(marshaled)
 }
diff --git a/api/v1/deneb/signedblockcontents_yaml.go b/api/v1/deneb/signedblockcontents_yaml.go
index 9daab627..f5a4ac0a 100644
--- a/api/v1/deneb/signedblockcontents_yaml.go
+++ b/api/v1/deneb/signedblockcontents_yaml.go
@@ -46,15 +46,15 @@ func (s *SignedBlockContents) MarshalYAML() ([]byte, error) {
 // UnmarshalYAML implements yaml.Unmarshaler.
 func (s *SignedBlockContents) UnmarshalYAML(input []byte) error {
 	// We unmarshal to the JSON struct to save on duplicate code.
-	var data signedBlockContentsJSON
-	if err := yaml.Unmarshal(input, &data); err != nil {
+	var unmarshaled signedBlockContentsJSON
+	if err := yaml.Unmarshal(input, &unmarshaled); err != nil {
 		return errors.Wrap(err, "failed to unmarshal YAML")
 	}
 
-	bytes, err := json.Marshal(data)
+	marshaled, err := json.Marshal(unmarshaled)
 	if err != nil {
 		return errors.Wrap(err, "failed to marshal JSON")
 	}
 
-	return s.UnmarshalJSON(bytes)
+	return s.UnmarshalJSON(marshaled)
 }
diff --git a/api/v1/event.go b/api/v1/event.go
index 5de4ddb8..8a991d39 100644
--- a/api/v1/event.go
+++ b/api/v1/event.go
@@ -27,7 +27,7 @@ type Event struct {
 	// Topic is the topic of the event.
 	Topic string
 	// Data is the data of the event.
-	Data interface{}
+	Data any
 }
 
 // SupportedEventTopics is a map of supported event topics.
@@ -45,8 +45,8 @@ var SupportedEventTopics = map[string]bool{
 
 // eventJSON is the spec representation of the struct.
 type eventJSON struct {
-	Topic string                 `json:"topic"`
-	Data  map[string]interface{} `json:"data"`
+	Topic string         `json:"topic"`
+	Data  map[string]any `json:"data"`
 }
 
 // MarshalJSON implements json.Marshaler.
@@ -56,7 +56,7 @@ func (e *Event) MarshalJSON() ([]byte, error) {
 	if err != nil {
 		return nil, errors.Wrap(err, "failed to marshal data")
 	}
-	var unmarshalled map[string]interface{}
+	var unmarshalled map[string]any
 	if err := json.Unmarshal(data, &unmarshalled); err != nil {
 		return nil, errors.Wrap(err, "failed to unmarshal data")
 	}
diff --git a/api/v1/forkchoice.go b/api/v1/forkchoice.go
index 1693810c..d890b4a9 100644
--- a/api/v1/forkchoice.go
+++ b/api/v1/forkchoice.go
@@ -173,20 +173,20 @@ type ForkChoiceNode struct {
 	// ExecutiionBlockHash is the execution block hash of the node.
 	ExecutionBlockHash phase0.Root
 	// ExtraData is the extra data of the node.
-	ExtraData map[string]interface{}
+	ExtraData map[string]any
 }
 
 // forkChoiceNodeJSON is the json representation of the struct.
 type forkChoiceNodeJSON struct {
-	Slot               string                 `json:"slot"`
-	BlockRoot          string                 `json:"block_root"`
-	ParentRoot         string                 `json:"parent_root"`
-	JustifiedEpoch     string                 `json:"justified_epoch"`
-	FinalizedEpoch     string                 `json:"finalized_epoch"`
-	Weight             string                 `json:"weight"`
-	Validity           string                 `json:"validity"`
-	ExecutionBlockHash string                 `json:"execution_block_hash"`
-	ExtraData          map[string]interface{} `json:"extra_data,omitempty"`
+	Slot               string         `json:"slot"`
+	BlockRoot          string         `json:"block_root"`
+	ParentRoot         string         `json:"parent_root"`
+	JustifiedEpoch     string         `json:"justified_epoch"`
+	FinalizedEpoch     string         `json:"finalized_epoch"`
+	Weight             string         `json:"weight"`
+	Validity           string         `json:"validity"`
+	ExecutionBlockHash string         `json:"execution_block_hash"`
+	ExtraData          map[string]any `json:"extra_data,omitempty"`
 }
 
 // MarshalJSON implements json.Marshaler.
diff --git a/api/versionedsignedproposal.go b/api/versionedsignedproposal.go
index 41de741a..0993661e 100644
--- a/api/versionedsignedproposal.go
+++ b/api/versionedsignedproposal.go
@@ -43,7 +43,7 @@ type VersionedSignedProposal struct {
 	DenebBlinded     *apiv1deneb.SignedBlindedBeaconBlock
 }
 
-// AssertPresnet throws an error if the expected proposal
+// AssertPresent throws an error if the expected proposal
 // given the version and blinded fields is not present.
 func (v *VersionedSignedProposal) AssertPresent() error {
 	switch v.Version {
diff --git a/auto/service.go b/auto/service.go
index 06920648..7bf31570 100644
--- a/auto/service.go
+++ b/auto/service.go
@@ -16,7 +16,7 @@ package auto
 import (
 	"context"
 
-	client "github.com/attestantio/go-eth2-client"
+	consensusclient "github.com/attestantio/go-eth2-client"
 	"github.com/attestantio/go-eth2-client/http"
 	"github.com/pkg/errors"
 	"github.com/rs/zerolog"
@@ -28,7 +28,7 @@ var log zerolog.Logger
 
 // New creates a new Ethereum 2 client service, trying different implementations at the given address.
 // Deprecated.  Use the `http` module instead.
-func New(ctx context.Context, params ...Parameter) (client.Service, error) {
+func New(ctx context.Context, params ...Parameter) (consensusclient.Service, error) {
 	parameters, err := parseAndCheckParameters(params...)
 	if err != nil {
 		return nil, errors.Wrap(err, "problem with parameters")
@@ -51,7 +51,7 @@ func New(ctx context.Context, params ...Parameter) (client.Service, error) {
 	return nil, errors.New("failed to connect to Ethereum 2 client with any known method")
 }
 
-func tryHTTP(ctx context.Context, parameters *parameters) (client.Service, error) {
+func tryHTTP(ctx context.Context, parameters *parameters) (consensusclient.Service, error) {
 	httpParameters := make([]http.Parameter, 0)
 	httpParameters = append(httpParameters, http.WithLogLevel(parameters.logLevel))
 	httpParameters = append(httpParameters, http.WithAddress(parameters.address))
diff --git a/go.mod b/go.mod
index fb3e3e48..8ba9d963 100644
--- a/go.mod
+++ b/go.mod
@@ -4,19 +4,20 @@ go 1.20
 
 require (
 	github.com/ferranbt/fastssz v0.1.3
-	github.com/goccy/go-yaml v1.9.2
+	github.com/goccy/go-yaml v1.11.3
 	github.com/golang/snappy v0.0.4
 	github.com/holiman/uint256 v1.2.4
 	github.com/huandu/go-clone v1.6.0
 	github.com/huandu/go-clone/generic v1.6.0
 	github.com/pkg/errors v0.9.1
 	github.com/prometheus/client_golang v1.16.0
-	github.com/prysmaticlabs/go-bitfield v0.0.0-20210809151128-385d8c5e3fb7
+	github.com/prysmaticlabs/go-bitfield v0.0.0-20240328144219-a1caa50c3a1e
 	github.com/r3labs/sse/v2 v2.10.0
 	github.com/rs/zerolog v1.32.0
 	github.com/stretchr/testify v1.8.4
 	go.opentelemetry.io/otel v1.16.0
-	golang.org/x/crypto v0.20.0
+	go.opentelemetry.io/otel/trace v1.16.0
+	golang.org/x/crypto v0.22.0
 	golang.org/x/sync v0.2.0
 )
 
@@ -41,9 +42,8 @@ require (
 	github.com/prometheus/procfs v0.10.1 // indirect
 	github.com/rogpeppe/go-internal v1.11.0 // indirect
 	go.opentelemetry.io/otel/metric v1.16.0 // indirect
-	go.opentelemetry.io/otel/trace v1.16.0 // indirect
 	golang.org/x/net v0.21.0 // indirect
-	golang.org/x/sys v0.17.0 // indirect
+	golang.org/x/sys v0.19.0 // indirect
 	golang.org/x/xerrors v0.0.0-20231012003039-104605ab7028 // indirect
 	google.golang.org/protobuf v1.30.0 // indirect
 	gopkg.in/cenkalti/backoff.v1 v1.1.0 // indirect
diff --git a/go.sum b/go.sum
index 9ae03b72..1488e36e 100644
--- a/go.sum
+++ b/go.sum
@@ -7,7 +7,6 @@ github.com/creack/pty v1.1.9/go.mod h1:oKZEueFk5CKHvIhNR5MUki03XCEU+Q6VDXinZuGJ3
 github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
 github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
-github.com/fatih/color v1.10.0/go.mod h1:ELkj/draVOlAH/xkhN6mQ50Qd0MPOk5AAr3maGEBuJM=
 github.com/fatih/color v1.16.0 h1:zmkK9Ngbjj+K0yRhTVONQh1p/HknKYSlNT+vZCzyokM=
 github.com/fatih/color v1.16.0/go.mod h1:fL2Sau1YI5c0pdGEVCbKQbLXB6edEj1ZgiY4NijnWvE=
 github.com/ferranbt/fastssz v0.1.3 h1:ZI+z3JH05h4kgmFXdHuR1aWYsgrg7o+Fw7/NCzM16Mo=
@@ -17,15 +16,11 @@ github.com/go-logr/logr v1.2.4 h1:g01GSCwiDw2xSZfjJ2/T9M+S6pFdcNtFYsp+Y43HYDQ=
 github.com/go-logr/logr v1.2.4/go.mod h1:jdQByPbusPIv2/zmleS9BjJVeZ6kBagPoEUsqbVz/1A=
 github.com/go-logr/stdr v1.2.2 h1:hSWxHoqTgW2S2qGc0LTAI563KZ5YKYRhT3MFKZMbjag=
 github.com/go-logr/stdr v1.2.2/go.mod h1:mMo/vtBO5dYbehREoey6XUKy/eSumjCCveDpRre4VKE=
-github.com/go-playground/assert/v2 v2.0.1/go.mod h1:VDjEfimB/XKnb+ZQfWdccd7VUvScMdVu0Titje2rxJ4=
 github.com/go-playground/locales v0.13.0 h1:HyWk6mgj5qFqCT5fjGBuRArbVDfE4hi8+e8ceBS/t7Q=
-github.com/go-playground/locales v0.13.0/go.mod h1:taPMhCMXrRLJO55olJkUXHZBHCxTMfnGwq/HNwmWNS8=
 github.com/go-playground/universal-translator v0.17.0 h1:icxd5fm+REJzpZx7ZfpaD876Lmtgy7VtROAbHHXk8no=
-github.com/go-playground/universal-translator v0.17.0/go.mod h1:UkSxE5sNxxRwHyU+Scu5vgOQjsIJAF8j9muTVoKLVtA=
 github.com/go-playground/validator/v10 v10.4.1 h1:pH2c5ADXtd66mxoE0Zm9SUhxE20r7aM3F26W0hOn+GE=
-github.com/go-playground/validator/v10 v10.4.1/go.mod h1:nlOn6nFhuKACm19sB/8EGNn9GlaMV7XkbRSipzJ0Ii4=
-github.com/goccy/go-yaml v1.9.2 h1:2Njwzw+0+pjU2gb805ZC1B/uBuAs2VcZ3K+ZgHwDs7w=
-github.com/goccy/go-yaml v1.9.2/go.mod h1:U/jl18uSupI5rdI2jmuCswEA2htH9eXfferR3KfscvA=
+github.com/goccy/go-yaml v1.11.3 h1:B3W9IdWbvrUu2OYQGwvU1nZtvMQJPBKgBUuweJjLj6I=
+github.com/goccy/go-yaml v1.11.3/go.mod h1:wKnAMd44+9JAAnGQpWVEgBzGt3YuTaQ4uXoHvE4m7WU=
 github.com/godbus/dbus/v5 v5.0.4/go.mod h1:xhWf0FNVPg57R7Z0UbKHbJfkEywrmjJnf7w5xrFpKfA=
 github.com/golang/protobuf v1.2.0/go.mod h1:6lQm79b+lXiMfvg/cZm0SGofjICqVBUtrP5yJMmIC1U=
 github.com/golang/protobuf v1.3.5/go.mod h1:6O5/vntMXwX2lRkT1hjjk0nAC1IDOTvTlVgjlRvqsdk=
@@ -50,11 +45,8 @@ github.com/kr/pretty v0.3.1 h1:flRD4NNwYAUpkphVc1HcthR4KEIFJ65n8Mw5qdRn3LE=
 github.com/kr/text v0.2.0 h1:5Nx0Ya0ZqY2ygV366QzturHI13Jq95ApcVaJBhpS+AY=
 github.com/kr/text v0.2.0/go.mod h1:eLer722TekiGuMkidMxC/pM04lWEeraHUUmBw8l2grE=
 github.com/leodido/go-urn v1.2.0 h1:hpXL4XnriNwQ/ABnpepYM/1vCLWNDfUNts8dX3xTG6Y=
-github.com/leodido/go-urn v1.2.0/go.mod h1:+8+nEpDfqqsY+g338gtMEUOtuK+4dEMhiQEgxpxOKII=
-github.com/mattn/go-colorable v0.1.8/go.mod h1:u6P/XSegPjTcexA+o6vUJrdnUu04hMope9wVRipJSqc=
 github.com/mattn/go-colorable v0.1.13 h1:fFA4WZxdEF4tXPZVKMLwD8oUnCTTo08duU7wxecdEvA=
 github.com/mattn/go-colorable v0.1.13/go.mod h1:7S9/ev0klgBDR4GtXTXX8a3vIGJpMovkB8vQcUbaXHg=
-github.com/mattn/go-isatty v0.0.12/go.mod h1:cbi8OIDigv2wuxKPP5vlRcQ1OAZbq2CE4Kysco4FUpU=
 github.com/mattn/go-isatty v0.0.16/go.mod h1:kYGgaQfpe5nmfYZH+SKPsOc2e4SrIfOl2e/yFXSvRLM=
 github.com/mattn/go-isatty v0.0.19/go.mod h1:W+V8PltTTMOvKvAeJH7IuucS94S2C6jfK/D7dTCTo3Y=
 github.com/mattn/go-isatty v0.0.20 h1:xfD0iDuEKnDkl03q4limB+vH+GxLEtL/jb4xVJSWWEY=
@@ -77,8 +69,8 @@ github.com/prometheus/common v0.42.0 h1:EKsfXEYo4JpWMHH5cg+KOUWeuJSov1Id8zGR8eeI
 github.com/prometheus/common v0.42.0/go.mod h1:xBwqVerjNdUDjgODMpudtOMwlOwf2SaTr1yjz4b7Zbc=
 github.com/prometheus/procfs v0.10.1 h1:kYK1Va/YMlutzCGazswoHKo//tZVlFpKYh+PymziUAg=
 github.com/prometheus/procfs v0.10.1/go.mod h1:nwNm2aOCAYw8uTR/9bWRREkZFxAUcWzPHWJq+XBB/FM=
-github.com/prysmaticlabs/go-bitfield v0.0.0-20210809151128-385d8c5e3fb7 h1:0tVE4tdWQK9ZpYygoV7+vS6QkDvQVySboMVEIxBJmXw=
-github.com/prysmaticlabs/go-bitfield v0.0.0-20210809151128-385d8c5e3fb7/go.mod h1:wmuf/mdK4VMD+jA9ThwcUKjg3a2XWM9cVfFYjDyY4j4=
+github.com/prysmaticlabs/go-bitfield v0.0.0-20240328144219-a1caa50c3a1e h1:ATgOe+abbzfx9kCPeXIW4fiWyDdxlwHw07j8UGhdTd4=
+github.com/prysmaticlabs/go-bitfield v0.0.0-20240328144219-a1caa50c3a1e/go.mod h1:wmuf/mdK4VMD+jA9ThwcUKjg3a2XWM9cVfFYjDyY4j4=
 github.com/r3labs/sse/v2 v2.10.0 h1:hFEkLLFY4LDifoHdiCN/LlGBAdVJYsANaLqNYa1l/v0=
 github.com/r3labs/sse/v2 v2.10.0/go.mod h1:Igau6Whc+F17QUgML1fYe1VPZzTV6EMCnYktEmkNJ7I=
 github.com/rogpeppe/go-internal v1.11.0 h1:cWPaGQEPrBb5/AsnsZesgZZ9yb1OQ+GOISoDNXVBh4M=
@@ -99,10 +91,8 @@ go.opentelemetry.io/otel/metric v1.16.0/go.mod h1:QE47cpOmkwipPiefDwo2wDzwJrlfxx
 go.opentelemetry.io/otel/trace v1.16.0 h1:8JRpaObFoW0pxuVPapkgH8UhHQj+bJW8jJsCZEu5MQs=
 go.opentelemetry.io/otel/trace v1.16.0/go.mod h1:Yt9vYq1SdNz3xdjZZK7wcXv1qv2pwLkqr2QVwea0ef0=
 golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
-golang.org/x/crypto v0.0.0-20200622213623-75b288015ac9/go.mod h1:LzIPMQfyMNhhGPhUkYOs5KpL4U8rLKemX1yGLhDgUto=
-golang.org/x/crypto v0.20.0 h1:jmAMJJZXr5KiCw05dfYK9QnqaqKLYXijU23lsEdcQqg=
-golang.org/x/crypto v0.20.0/go.mod h1:Xwo95rrVNIoSMx9wa1JroENMToLWn3RNVrTBpLHgZPQ=
-golang.org/x/net v0.0.0-20190404232315-eb5bcb51f2a3/go.mod h1:t9HGtf8HONx5eT2rtn7q6eTqICYqUVnKs3thJo3Qplg=
+golang.org/x/crypto v0.22.0 h1:g1v0xeRhjcugydODzvb3mEM9SQ0HGp9s/nh3COQ/C30=
+golang.org/x/crypto v0.22.0/go.mod h1:vr6Su+7cTlO45qkww3VDJlzDn0ctJvRgYbC2NvXHt+M=
 golang.org/x/net v0.0.0-20191116160921-f9c825593386/go.mod h1:z5CRVTTTmAJ677TzLLGU+0bjPO0LkuOLi4/5GtJWs/s=
 golang.org/x/net v0.21.0 h1:AQyQV4dYCvJ7vGmJyKki9+PBdyvhkSd8EIx/qb0AYv4=
 golang.org/x/net v0.21.0/go.mod h1:bIjVDfnllIU7BJ2DNgfnXvpSvtn8VRwhlsaeUTyUS44=
@@ -110,20 +100,14 @@ golang.org/x/sync v0.0.0-20181221193216-37e7f081c4d4/go.mod h1:RxMgew5VJxzue5/jJ
 golang.org/x/sync v0.2.0 h1:PUR+T4wwASmuSTYdKjYHI5TD22Wy5ogLU5qZCOLxBrI=
 golang.org/x/sync v0.2.0/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
 golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
-golang.org/x/sys v0.0.0-20190412213103-97732733099d/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
-golang.org/x/sys v0.0.0-20200116001909-b77594299b42/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
-golang.org/x/sys v0.0.0-20200223170610-d5e6a3e2c0ae/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20220811171246-fbc7d0a398ab/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/sys v0.5.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/sys v0.6.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/sys v0.12.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
-golang.org/x/sys v0.17.0 h1:25cE3gD+tdBA7lp7QfhuV+rJiE9YXTcS3VG1SqssI/Y=
-golang.org/x/sys v0.17.0/go.mod h1:/VUhepiaJMQUp4+oa/7Zr1D23ma6VTLIYjOOTFZPUcA=
+golang.org/x/sys v0.19.0 h1:q5f1RH2jigJ1MoAWp2KTp3gm5zAGFUTarQZ5U386+4o=
+golang.org/x/sys v0.19.0/go.mod h1:/VUhepiaJMQUp4+oa/7Zr1D23ma6VTLIYjOOTFZPUcA=
 golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
-golang.org/x/text v0.3.2/go.mod h1:bEr9sfX3Q8Zfm5fL9x+3itogRgK3+ptLWKqgva+5dAk=
-golang.org/x/tools v0.0.0-20180917221912-90fa682c2a6e/go.mod h1:n7NCudcB/nEzxVGmLbDWY5pfWTLqBcC2KZ6jyYvM4mQ=
 golang.org/x/xerrors v0.0.0-20191204190536-9bdfabe68543/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
-golang.org/x/xerrors v0.0.0-20200804184101-5ec99f83aff1/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
 golang.org/x/xerrors v0.0.0-20231012003039-104605ab7028 h1:+cNy6SZtPcJQH3LJVLOSmiC7MMxXNOb3PU/VUEz+EhU=
 golang.org/x/xerrors v0.0.0-20231012003039-104605ab7028/go.mod h1:NDW/Ps6MPRej6fsCIbMTohpP40sJ/P/vI1MoTEGwX90=
 google.golang.org/protobuf v1.26.0-rc.1/go.mod h1:jlhhOSvTdKEhbULTjvd4ARK9grFBp09yW+WbY/TyQbw=
diff --git a/http/attestationdata.go b/http/attestationdata.go
index 3f490b20..8e73efa8 100644
--- a/http/attestationdata.go
+++ b/http/attestationdata.go
@@ -53,7 +53,7 @@ func (s *Service) AttestationData(ctx context.Context,
 	}
 }
 
-func (s *Service) attestationDataFromJSON(_ context.Context,
+func (*Service) attestationDataFromJSON(_ context.Context,
 	opts *api.AttestationDataOpts,
 	httpResponse *httpResponse,
 ) (
diff --git a/http/attestationpool.go b/http/attestationpool.go
index e6038c85..ab2b10b0 100644
--- a/http/attestationpool.go
+++ b/http/attestationpool.go
@@ -53,7 +53,7 @@ func (s *Service) AttestationPool(ctx context.Context,
 	}
 }
 
-func (s *Service) attestationPoolFromJSON(_ context.Context,
+func (*Service) attestationPoolFromJSON(_ context.Context,
 	opts *api.AttestationPoolOpts,
 	httpResponse *httpResponse,
 ) (
diff --git a/http/beaconcommittees.go b/http/beaconcommittees.go
index fef059bd..fe1e289d 100644
--- a/http/beaconcommittees.go
+++ b/http/beaconcommittees.go
@@ -20,7 +20,7 @@ import (
 	"fmt"
 
 	client "github.com/attestantio/go-eth2-client"
-	api "github.com/attestantio/go-eth2-client/api"
+	"github.com/attestantio/go-eth2-client/api"
 	apiv1 "github.com/attestantio/go-eth2-client/api/v1"
 )
 
diff --git a/http/beaconstate.go b/http/beaconstate.go
index 0d62dfdd..6e61597b 100644
--- a/http/beaconstate.go
+++ b/http/beaconstate.go
@@ -62,7 +62,7 @@ func (s *Service) BeaconState(ctx context.Context,
 	}
 }
 
-func (s *Service) beaconStateFromSSZ(res *httpResponse) (*api.Response[*spec.VersionedBeaconState], error) {
+func (*Service) beaconStateFromSSZ(res *httpResponse) (*api.Response[*spec.VersionedBeaconState], error) {
 	response := &api.Response[*spec.VersionedBeaconState]{
 		Data: &spec.VersionedBeaconState{
 			Version: res.consensusVersion,
@@ -103,7 +103,7 @@ func (s *Service) beaconStateFromSSZ(res *httpResponse) (*api.Response[*spec.Ver
 	return response, nil
 }
 
-func (s *Service) beaconStateFromJSON(res *httpResponse) (*api.Response[*spec.VersionedBeaconState], error) {
+func (*Service) beaconStateFromJSON(res *httpResponse) (*api.Response[*spec.VersionedBeaconState], error) {
 	response := &api.Response[*spec.VersionedBeaconState]{
 		Data: &spec.VersionedBeaconState{
 			Version: res.consensusVersion,
diff --git a/http/blindedproposal.go b/http/blindedproposal.go
index 11724fba..f1f8d143 100644
--- a/http/blindedproposal.go
+++ b/http/blindedproposal.go
@@ -108,7 +108,7 @@ func (s *Service) BlindedProposal(ctx context.Context,
 	return response, nil
 }
 
-func (s *Service) blindedProposalFromSSZ(res *httpResponse) (*api.Response[*api.VersionedBlindedProposal], error) {
+func (*Service) blindedProposalFromSSZ(res *httpResponse) (*api.Response[*api.VersionedBlindedProposal], error) {
 	response := &api.Response[*api.VersionedBlindedProposal]{
 		Data: &api.VersionedBlindedProposal{
 			Version: res.consensusVersion,
@@ -139,7 +139,7 @@ func (s *Service) blindedProposalFromSSZ(res *httpResponse) (*api.Response[*api.
 	return response, nil
 }
 
-func (s *Service) blindedProposalFromJSON(res *httpResponse) (*api.Response[*api.VersionedBlindedProposal], error) {
+func (*Service) blindedProposalFromJSON(res *httpResponse) (*api.Response[*api.VersionedBlindedProposal], error) {
 	response := &api.Response[*api.VersionedBlindedProposal]{
 		Data: &api.VersionedBlindedProposal{
 			Version: res.consensusVersion,
diff --git a/http/blobsidecars.go b/http/blobsidecars.go
index 7743305c..d6f3cfe6 100644
--- a/http/blobsidecars.go
+++ b/http/blobsidecars.go
@@ -63,7 +63,7 @@ func (s *Service) BlobSidecars(ctx context.Context,
 	return response, nil
 }
 
-func (s *Service) blobSidecarsFromSSZ(res *httpResponse) (*api.Response[[]*deneb.BlobSidecar], error) {
+func (*Service) blobSidecarsFromSSZ(res *httpResponse) (*api.Response[[]*deneb.BlobSidecar], error) {
 	response := &api.Response[[]*deneb.BlobSidecar]{}
 
 	data := &api.BlobSidecars{}
@@ -76,7 +76,7 @@ func (s *Service) blobSidecarsFromSSZ(res *httpResponse) (*api.Response[[]*deneb
 	return response, nil
 }
 
-func (s *Service) blobSidecarsFromJSON(res *httpResponse) (*api.Response[[]*deneb.BlobSidecar], error) {
+func (*Service) blobSidecarsFromJSON(res *httpResponse) (*api.Response[[]*deneb.BlobSidecar], error) {
 	response := &api.Response[[]*deneb.BlobSidecar]{}
 
 	var err error
diff --git a/http/errors.go b/http/errors.go
new file mode 100644
index 00000000..53488092
--- /dev/null
+++ b/http/errors.go
@@ -0,0 +1,19 @@
+// Copyright © 2024 Attestant Limited.
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package http
+
+import "errors"
+
+// ErrIncorrectType is returned when the multi client obtain a response type it is not expecting.
+var ErrIncorrectType = errors.New("incorrect response type")
diff --git a/http/events.go b/http/events.go
index 8d8ada7e..fbaaace8 100644
--- a/http/events.go
+++ b/http/events.go
@@ -25,7 +25,7 @@ import (
 	"strings"
 	"time"
 
-	client "github.com/attestantio/go-eth2-client"
+	consensusclient "github.com/attestantio/go-eth2-client"
 	api "github.com/attestantio/go-eth2-client/api/v1"
 	"github.com/attestantio/go-eth2-client/spec/altair"
 	"github.com/attestantio/go-eth2-client/spec/capella"
@@ -35,12 +35,12 @@ import (
 )
 
 // Events feeds requested events with the given topics to the supplied handler.
-func (s *Service) Events(ctx context.Context, topics []string, handler client.EventHandlerFunc) error {
+func (s *Service) Events(ctx context.Context, topics []string, handler consensusclient.EventHandlerFunc) error {
 	if err := s.assertIsActive(ctx); err != nil {
 		return err
 	}
 	if len(topics) == 0 {
-		return errors.Join(errors.New("no topics supplied"), client.ErrInvalidOptions)
+		return errors.Join(errors.New("no topics supplied"), consensusclient.ErrInvalidOptions)
 	}
 
 	// #nosec G404
@@ -58,10 +58,10 @@ func (s *Service) Events(ctx context.Context, topics []string, handler client.Ev
 	if err != nil {
 		return errors.Join(errors.New("invalid endpoint"), err)
 	}
-	url := s.base.ResolveReference(reference).String()
-	log.Trace().Str("url", url).Msg("GET request to events stream")
+	callURL := s.base.ResolveReference(reference).String()
+	log.Trace().Str("url", callURL).Msg("GET request to events stream")
 
-	client := sse.NewClient(url)
+	client := sse.NewClient(callURL)
 	client.Connection.Transport = &http.Transport{
 		Dial: (&net.Dialer{
 			Timeout:   2 * time.Second,
@@ -92,7 +92,7 @@ func (s *Service) Events(ctx context.Context, topics []string, handler client.Ev
 }
 
 // handleEvent parses an event and passes it on to the handler.
-func (s *Service) handleEvent(ctx context.Context, msg *sse.Event, handler client.EventHandlerFunc) {
+func (*Service) handleEvent(ctx context.Context, msg *sse.Event, handler consensusclient.EventHandlerFunc) {
 	log := zerolog.Ctx(ctx)
 
 	if handler == nil {
diff --git a/http/farfutureepoch.go b/http/farfutureepoch.go
index 19dc2b53..d15b10a7 100644
--- a/http/farfutureepoch.go
+++ b/http/farfutureepoch.go
@@ -20,6 +20,6 @@ import (
 )
 
 // FarFutureEpoch provides the values for FAR_FUTURE_EOPCH of the chain.
-func (s *Service) FarFutureEpoch(_ context.Context) (phase0.Epoch, error) {
+func (*Service) FarFutureEpoch(_ context.Context) (phase0.Epoch, error) {
 	return phase0.Epoch(0xffffffffffffffff), nil
 }
diff --git a/http/http.go b/http/http.go
index cbe62c73..8e5c161f 100644
--- a/http/http.go
+++ b/http/http.go
@@ -47,11 +47,11 @@ func (s *Service) post(ctx context.Context, endpoint string, body io.Reader) (io
 		e.Str("body", string(bodyBytes)).Msg("POST request")
 	}
 
-	url := urlForCall(s.base, endpoint, "")
+	callURL := urlForCall(s.base, endpoint, "")
 
 	opCtx, cancel := context.WithTimeout(ctx, s.timeout)
 	defer cancel()
-	req, err := http.NewRequestWithContext(opCtx, http.MethodPost, url.String(), body)
+	req, err := http.NewRequestWithContext(opCtx, http.MethodPost, callURL.String(), body)
 	if err != nil {
 		return nil, errors.Join(errors.New("failed to create POST request"), err)
 	}
@@ -65,7 +65,7 @@ func (s *Service) post(ctx context.Context, endpoint string, body io.Reader) (io
 	resp, err := s.client.Do(req)
 	if err != nil {
 		go s.CheckConnectionState(ctx)
-		s.monitorPostComplete(ctx, url.Path, "failed")
+		s.monitorPostComplete(ctx, callURL.Path, "failed")
 
 		return nil, errors.Join(errors.New("failed to call POST endpoint"), err)
 	}
@@ -80,7 +80,7 @@ func (s *Service) post(ctx context.Context, endpoint string, body io.Reader) (io
 	if statusFamily != 2 {
 		log.Debug().Int("status_code", resp.StatusCode).Str("data", string(data)).Msg("POST failed")
 
-		s.monitorPostComplete(ctx, url.Path, "failed")
+		s.monitorPostComplete(ctx, callURL.Path, "failed")
 
 		return nil, &api.Error{
 			Method:     http.MethodPost,
@@ -91,7 +91,7 @@ func (s *Service) post(ctx context.Context, endpoint string, body io.Reader) (io
 	}
 
 	log.Trace().Str("response", string(data)).Msg("POST response")
-	s.monitorPostComplete(ctx, url.Path, "succeeded")
+	s.monitorPostComplete(ctx, callURL.Path, "succeeded")
 
 	return bytes.NewReader(data), nil
 }
@@ -130,13 +130,13 @@ func (s *Service) post2(ctx context.Context,
 		}
 	}
 
-	url := urlForCall(s.base, endpoint, query)
-	log.Trace().Str("url", url.String()).Msg("URL to POST")
-	span.SetAttributes(attribute.String("url", url.String()))
+	callURL := urlForCall(s.base, endpoint, query)
+	log.Trace().Str("url", callURL.String()).Msg("URL to POST")
+	span.SetAttributes(attribute.String("url", callURL.String()))
 
 	opCtx, cancel := context.WithTimeout(ctx, s.timeout)
 	defer cancel()
-	req, err := http.NewRequestWithContext(opCtx, http.MethodPost, url.String(), body)
+	req, err := http.NewRequestWithContext(opCtx, http.MethodPost, callURL.String(), body)
 	if err != nil {
 		return nil, errors.Join(errors.New("failed to create POST request"), err)
 	}
@@ -165,7 +165,7 @@ func (s *Service) post2(ctx context.Context,
 		}
 
 		span.SetStatus(codes.Error, err.Error())
-		s.monitorPostComplete(ctx, url.Path, "failed")
+		s.monitorPostComplete(ctx, callURL.Path, "failed")
 
 		return nil, errors.Join(errors.New("failed to call POST endpoint"), err)
 	}
@@ -189,7 +189,7 @@ func (s *Service) post2(ctx context.Context,
 		}
 
 		span.SetStatus(codes.Error, err.Error())
-		s.monitorPostComplete(ctx, url.Path, "failed")
+		s.monitorPostComplete(ctx, callURL.Path, "failed")
 
 		return nil, errors.Join(errors.New("failed to read POST response"), err)
 	}
@@ -198,7 +198,7 @@ func (s *Service) post2(ctx context.Context,
 		// Nothing returned.  This is not considered an error.
 		span.AddEvent("Received empty response")
 		log.Trace().Msg("Endpoint returned no content")
-		s.monitorPostComplete(ctx, url.Path, "succeeded")
+		s.monitorPostComplete(ctx, callURL.Path, "succeeded")
 
 		return res, nil
 	}
@@ -226,7 +226,7 @@ func (s *Service) post2(ctx context.Context,
 		log.Debug().Int("status_code", resp.StatusCode).RawJSON("response", trimmedResponse).Msg("POST failed")
 
 		span.SetStatus(codes.Error, fmt.Sprintf("Status code %d", resp.StatusCode))
-		s.monitorPostComplete(ctx, url.Path, "failed")
+		s.monitorPostComplete(ctx, callURL.Path, "failed")
 
 		return nil, &api.Error{
 			Method:     http.MethodPost,
@@ -236,7 +236,7 @@ func (s *Service) post2(ctx context.Context,
 		}
 	}
 
-	s.monitorPostComplete(ctx, url.Path, "succeeded")
+	s.monitorPostComplete(ctx, callURL.Path, "succeeded")
 
 	return res, nil
 }
@@ -276,9 +276,9 @@ func (s *Service) get(ctx context.Context,
 	log := s.log.With().Str("id", fmt.Sprintf("%02x", rand.Int31())).Str("address", s.address).Str("endpoint", endpoint).Logger()
 	log.Trace().Msg("GET request")
 
-	url := urlForCall(s.base, endpoint, query)
-	log.Trace().Str("url", url.String()).Msg("URL to GET")
-	span.SetAttributes(attribute.String("url", url.String()))
+	callURL := urlForCall(s.base, endpoint, query)
+	log.Trace().Str("url", callURL.String()).Msg("URL to GET")
+	span.SetAttributes(attribute.String("url", callURL.String()))
 
 	timeout := s.timeout
 	if opts.Timeout != 0 {
@@ -287,7 +287,7 @@ func (s *Service) get(ctx context.Context,
 
 	opCtx, cancel := context.WithTimeout(ctx, timeout)
 	defer cancel()
-	req, err := http.NewRequestWithContext(opCtx, http.MethodGet, url.String(), nil)
+	req, err := http.NewRequestWithContext(opCtx, http.MethodGet, callURL.String(), nil)
 	if err != nil {
 		span.SetStatus(codes.Error, "Failed to create request")
 
@@ -310,7 +310,7 @@ func (s *Service) get(ctx context.Context,
 			// We don't consider context canceled to be a potential connection issue, as the user canceled the context.
 		case errors.Is(err, context.DeadlineExceeded):
 			// We don't consider context deadline exceeded to be a potential connection issue, as the user selected the deadline.
-		case strings.HasSuffix(url.String(), "/node/syncing"):
+		case strings.HasSuffix(callURL.String(), "/node/syncing"):
 			// Special case; if we have called the syncing endpoint and it failed then we don't check the connectino status, as
 			// that calls the syncing endpoint itself and so we find ourselves in an endless loop.
 		default:
@@ -319,7 +319,7 @@ func (s *Service) get(ctx context.Context,
 		}
 
 		span.SetStatus(codes.Error, err.Error())
-		s.monitorGetComplete(ctx, url.Path, "failed")
+		s.monitorGetComplete(ctx, callURL.Path, "failed")
 
 		return nil, errors.Join(errors.New("failed to call GET endpoint"), err)
 	}
@@ -347,7 +347,7 @@ func (s *Service) get(ctx context.Context,
 		}
 
 		span.SetStatus(codes.Error, err.Error())
-		s.monitorGetComplete(ctx, url.Path, "failed")
+		s.monitorGetComplete(ctx, callURL.Path, "failed")
 
 		return nil, errors.Join(errors.New("failed to read GET response"), err)
 	}
@@ -356,7 +356,7 @@ func (s *Service) get(ctx context.Context,
 		// Nothing returned.  This is not considered an error.
 		span.AddEvent("Received empty response")
 		log.Trace().Msg("Endpoint returned no content")
-		s.monitorGetComplete(ctx, url.Path, "succeeded")
+		s.monitorGetComplete(ctx, callURL.Path, "succeeded")
 
 		return res, nil
 	}
@@ -372,8 +372,8 @@ func (s *Service) get(ctx context.Context,
 	))
 
 	if res.contentType == ContentTypeJSON {
-		trimmedResponse := bytes.ReplaceAll(bytes.ReplaceAll(res.body, []byte{0x0a}, []byte{}), []byte{0x0d}, []byte{})
 		if e := log.Trace(); e.Enabled() {
+			trimmedResponse := bytes.ReplaceAll(bytes.ReplaceAll(res.body, []byte{0x0a}, []byte{}), []byte{0x0d}, []byte{})
 			e.RawJSON("body", trimmedResponse).Msg("GET response")
 		}
 	}
@@ -384,7 +384,7 @@ func (s *Service) get(ctx context.Context,
 		log.Debug().Int("status_code", resp.StatusCode).RawJSON("response", trimmedResponse).Msg("GET failed")
 
 		span.SetStatus(codes.Error, fmt.Sprintf("Status code %d", resp.StatusCode))
-		s.monitorGetComplete(ctx, url.Path, "failed")
+		s.monitorGetComplete(ctx, callURL.Path, "failed")
 
 		return nil, &api.Error{
 			Method:     http.MethodGet,
@@ -398,7 +398,7 @@ func (s *Service) get(ctx context.Context,
 		return nil, errors.Join(errors.New("failed to parse consensus version"), err)
 	}
 
-	s.monitorGetComplete(ctx, url.Path, "succeeded")
+	s.monitorGetComplete(ctx, callURL.Path, "succeeded")
 
 	return res, nil
 }
@@ -466,7 +466,10 @@ func metadataFromHeaders(headers map[string]string) map[string]any {
 }
 
 // urlForCall patches together a URL for a call.
-func urlForCall(base *url.URL, endpoint string, query string) *url.URL {
+func urlForCall(base *url.URL,
+	endpoint string,
+	query string,
+) *url.URL {
 	callURL := *base
 	callURL.Path = endpoint
 	if callURL.RawQuery == "" {
diff --git a/http/json.go b/http/json.go
index 43eb0c34..08997fab 100644
--- a/http/json.go
+++ b/http/json.go
@@ -21,7 +21,10 @@ func decodeJSONResponse[T any](body io.Reader, res T) (T, map[string]any, error)
 		return res, nil, errors.Join(errors.New("failed to parse JSON"), err)
 	}
 
-	data := clone.Clone(res).(T)
+	data, isCorrectType := clone.Clone(res).(T)
+	if !isCorrectType {
+		return res, nil, ErrIncorrectType
+	}
 	metadata := make(map[string]any)
 	for k, v := range decoded {
 		switch k {
diff --git a/http/proposal.go b/http/proposal.go
index ca33eb80..f99dd816 100644
--- a/http/proposal.go
+++ b/http/proposal.go
@@ -224,7 +224,7 @@ func (s *Service) beaconBlockProposalFromJSON(res *httpResponse) (*api.Response[
 	return response, nil
 }
 
-func (s *Service) populateProposalDataFromHeaders(response *api.Response[*api.VersionedProposal],
+func (*Service) populateProposalDataFromHeaders(response *api.Response[*api.VersionedProposal],
 	headers map[string]string,
 ) error {
 	for k, v := range headers {
diff --git a/http/service.go b/http/service.go
index 7895230b..a0666ec6 100644
--- a/http/service.go
+++ b/http/service.go
@@ -48,7 +48,7 @@ type Service struct {
 	// lifetime of a beacon node.
 	genesis              *apiv1.Genesis
 	genesisMutex         sync.RWMutex
-	spec                 map[string]interface{}
+	spec                 map[string]any
 	specMutex            sync.RWMutex
 	depositContract      *apiv1.DepositContract
 	depositContractMutex sync.RWMutex
@@ -230,7 +230,7 @@ func (s *Service) checkDVT(ctx context.Context) error {
 }
 
 // Name provides the name of the service.
-func (s *Service) Name() string {
+func (*Service) Name() string {
 	return "Standard (HTTP)"
 }
 
@@ -240,7 +240,7 @@ func (s *Service) Address() string {
 }
 
 // close closes the service, freeing up resources.
-func (s *Service) close() {
+func (*Service) close() {
 }
 
 // CheckConnectionState checks the connection state for the client, potentially updating
diff --git a/http/signedbeaconblock.go b/http/signedbeaconblock.go
index f4bc3c00..2070fa92 100644
--- a/http/signedbeaconblock.go
+++ b/http/signedbeaconblock.go
@@ -65,7 +65,7 @@ func (s *Service) SignedBeaconBlock(ctx context.Context,
 	return response, nil
 }
 
-func (s *Service) signedBeaconBlockFromSSZ(res *httpResponse) (*api.Response[*spec.VersionedSignedBeaconBlock], error) {
+func (*Service) signedBeaconBlockFromSSZ(res *httpResponse) (*api.Response[*spec.VersionedSignedBeaconBlock], error) {
 	response := &api.Response[*spec.VersionedSignedBeaconBlock]{
 		Data: &spec.VersionedSignedBeaconBlock{
 			Version: res.consensusVersion,
@@ -106,7 +106,7 @@ func (s *Service) signedBeaconBlockFromSSZ(res *httpResponse) (*api.Response[*sp
 	return response, nil
 }
 
-func (s *Service) signedBeaconBlockFromJSON(res *httpResponse) (*api.Response[*spec.VersionedSignedBeaconBlock], error) {
+func (*Service) signedBeaconBlockFromJSON(res *httpResponse) (*api.Response[*spec.VersionedSignedBeaconBlock], error) {
 	response := &api.Response[*spec.VersionedSignedBeaconBlock]{
 		Data: &spec.VersionedSignedBeaconBlock{
 			Version: res.consensusVersion,
diff --git a/http/signedbeaconblock_test.go b/http/signedbeaconblock_test.go
index 14b83249..6086c826 100644
--- a/http/signedbeaconblock_test.go
+++ b/http/signedbeaconblock_test.go
@@ -15,6 +15,7 @@ package http_test
 
 import (
 	"context"
+	"errors"
 	"os"
 	"testing"
 
@@ -51,8 +52,15 @@ func TestSignedBeaconBlock(t *testing.T) {
 	for _, test := range tests {
 		t.Run(test.name, func(t *testing.T) {
 			response, err := service.(client.SignedBeaconBlockProvider).SignedBeaconBlock(ctx, test.opts)
-			require.NoError(t, err)
-			require.NotNil(t, response)
+			if err != nil {
+				// The beacon node we are talking to may not have the block.
+				var apiError *api.Error
+				require.True(t, errors.As(err, &apiError))
+				require.Equal(t, 404, apiError.StatusCode)
+			} else {
+				require.NoError(t, err)
+				require.NotNil(t, response)
+			}
 		})
 	}
 }
diff --git a/http/slotduration.go b/http/slotduration.go
index aaa8b608..7dac2959 100644
--- a/http/slotduration.go
+++ b/http/slotduration.go
@@ -31,5 +31,10 @@ func (s *Service) SlotDuration(ctx context.Context) (time.Duration, error) {
 		return 0, err
 	}
 
-	return response.Data["SECONDS_PER_SLOT"].(time.Duration), nil
+	res, isCorrectType := response.Data["SECONDS_PER_SLOT"].(time.Duration)
+	if !isCorrectType {
+		return 0, ErrIncorrectType
+	}
+
+	return res, nil
 }
diff --git a/http/slotsperepoch.go b/http/slotsperepoch.go
index 95efc500..1bd0a797 100644
--- a/http/slotsperepoch.go
+++ b/http/slotsperepoch.go
@@ -30,5 +30,10 @@ func (s *Service) SlotsPerEpoch(ctx context.Context) (uint64, error) {
 		return 0, err
 	}
 
-	return response.Data["SLOTS_PER_EPOCH"].(uint64), nil
+	res, isCorrectType := response.Data["SLOTS_PER_EPOCH"].(uint64)
+	if !isCorrectType {
+		return 0, ErrIncorrectType
+	}
+
+	return res, nil
 }
diff --git a/http/stateid.go b/http/stateid.go
index 390b3871..9421b1ae 100644
--- a/http/stateid.go
+++ b/http/stateid.go
@@ -25,7 +25,7 @@ import (
 )
 
 // SlotFromStateID parses the state ID and returns the relevant slot.
-func (s *Service) SlotFromStateID(_ context.Context, stateID string) (phase0.Slot, error) {
+func (*Service) SlotFromStateID(_ context.Context, stateID string) (phase0.Slot, error) {
 	var slot phase0.Slot
 	switch {
 	case stateID == "genesis":
diff --git a/http/submitbeaconblock_test.go b/http/submitbeaconblock_test.go
index 58dab7c6..4cb260d8 100644
--- a/http/submitbeaconblock_test.go
+++ b/http/submitbeaconblock_test.go
@@ -1,4 +1,4 @@
-// Copyright © 2020, 2021 Attestant Limited.
+// Copyright © 2020 - 2024 Attestant Limited.
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
 // You may obtain a copy of the License at
@@ -83,6 +83,13 @@ func TestSubmitBeaconBlock(t *testing.T) {
 			require.NoError(t, err)
 			require.NotNil(t, res)
 
+			if res.Data.Version != spec.DataVersionPhase0 &&
+				res.Data.Version != spec.DataVersionAltair &&
+				res.Data.Version != spec.DataVersionBellatrix &&
+				res.Data.Version != spec.DataVersionCapella {
+				t.Skip("proposal version not supported by endpoint, skipping test")
+			}
+
 			signedBeaconBlock := &spec.VersionedSignedBeaconBlock{}
 			switch {
 			case res.Data.Phase0 != nil:
diff --git a/http/submitproposal.go b/http/submitproposal.go
index 6580cd4d..0343093c 100644
--- a/http/submitproposal.go
+++ b/http/submitproposal.go
@@ -92,7 +92,7 @@ func (s *Service) submitProposalData(ctx context.Context,
 	return body, contentType, nil
 }
 
-func (s *Service) submitProposalJSON(_ context.Context,
+func (*Service) submitProposalJSON(_ context.Context,
 	proposal *api.VersionedSignedProposal,
 ) (
 	[]byte,
@@ -126,7 +126,7 @@ func (s *Service) submitProposalJSON(_ context.Context,
 	return specJSON, nil
 }
 
-func (s *Service) submitProposalSSZ(_ context.Context,
+func (*Service) submitProposalSSZ(_ context.Context,
 	proposal *api.VersionedSignedProposal,
 ) (
 	[]byte,
diff --git a/http/submitproposal_test.go b/http/submitproposal_test.go
index 50be39bb..a80ecdb0 100644
--- a/http/submitproposal_test.go
+++ b/http/submitproposal_test.go
@@ -21,11 +21,13 @@ import (
 
 	client "github.com/attestantio/go-eth2-client"
 	"github.com/attestantio/go-eth2-client/api"
+	apiv1deneb "github.com/attestantio/go-eth2-client/api/v1/deneb"
 	"github.com/attestantio/go-eth2-client/http"
 	"github.com/attestantio/go-eth2-client/spec"
 	"github.com/attestantio/go-eth2-client/spec/altair"
 	"github.com/attestantio/go-eth2-client/spec/bellatrix"
 	"github.com/attestantio/go-eth2-client/spec/capella"
+	"github.com/attestantio/go-eth2-client/spec/deneb"
 	"github.com/attestantio/go-eth2-client/spec/phase0"
 	"github.com/stretchr/testify/require"
 )
@@ -109,6 +111,14 @@ func TestSubmitProposal(t *testing.T) {
 					Message:   res.Data.Capella,
 					Signature: phase0.BLSSignature([96]byte{0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00}),
 				}
+			case res.Data.Deneb != nil:
+				signedBeaconBlock.Version = spec.DataVersionDeneb
+				signedBeaconBlock.Deneb = &apiv1deneb.SignedBlockContents{
+					SignedBlock: &deneb.SignedBeaconBlock{
+						Message:   res.Data.Deneb.Block,
+						Signature: phase0.BLSSignature([96]byte{0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00}),
+					},
+				}
 			default:
 				t.Fatalf("unknown block version %s", res.Data.Version.String())
 			}
diff --git a/http/submitvalidatorregistrations.go b/http/submitvalidatorregistrations.go
index a36aa526..6ca41a37 100644
--- a/http/submitvalidatorregistrations.go
+++ b/http/submitvalidatorregistrations.go
@@ -35,7 +35,7 @@ func (s *Service) SubmitValidatorRegistrations(ctx context.Context, registration
 
 	// Unwrap versioned registrations.
 	var version *spec.BuilderVersion
-	var unversionedRegistrations []interface{}
+	var unversionedRegistrations []any
 
 	for i := range registrations {
 		if registrations[i] == nil {
diff --git a/http/targetaggregatorspercommittee.go b/http/targetaggregatorspercommittee.go
index dab1e5da..7b5b720c 100644
--- a/http/targetaggregatorspercommittee.go
+++ b/http/targetaggregatorspercommittee.go
@@ -30,5 +30,10 @@ func (s *Service) TargetAggregatorsPerCommittee(ctx context.Context) (uint64, er
 		return 0, err
 	}
 
-	return response.Data["TARGET_AGGREGATORS_PER_COMMITTEE"].(uint64), nil
+	res, isCorrectType := response.Data["TARGET_AGGREGATORS_PER_COMMITTEE"].(uint64)
+	if !isCorrectType {
+		return 0, ErrIncorrectType
+	}
+
+	return res, nil
 }
diff --git a/http/validatorbalances.go b/http/validatorbalances.go
index 24b45824..2a40fd0e 100644
--- a/http/validatorbalances.go
+++ b/http/validatorbalances.go
@@ -108,7 +108,7 @@ func (s *Service) chunkedValidatorBalances(ctx context.Context,
 	}, nil
 }
 
-func (s *Service) validatorBalancesFromJSON(_ context.Context,
+func (*Service) validatorBalancesFromJSON(_ context.Context,
 	httpResponse *httpResponse,
 ) (
 	*api.Response[map[phase0.ValidatorIndex]phase0.Gwei],
diff --git a/mock/aggregateandproofdomain.go b/mock/aggregateandproofdomain.go
index 06cd0639..ddfd1c10 100644
--- a/mock/aggregateandproofdomain.go
+++ b/mock/aggregateandproofdomain.go
@@ -20,6 +20,6 @@ import (
 )
 
 // AggregateAndProofDomain provides the aggregate and proof domain.
-func (s *Service) AggregateAndProofDomain(_ context.Context) (spec.DomainType, error) {
+func (*Service) AggregateAndProofDomain(_ context.Context) (spec.DomainType, error) {
 	return spec.DomainType{0x06, 0x00, 0x00, 0x00}, nil
 }
diff --git a/mock/aggregateattestation.go b/mock/aggregateattestation.go
index 2d0bdc11..8f5765d1 100644
--- a/mock/aggregateattestation.go
+++ b/mock/aggregateattestation.go
@@ -21,7 +21,7 @@ import (
 )
 
 // AggregateAttestation fetches the aggregate attestation given an attestation.
-func (s *Service) AggregateAttestation(_ context.Context,
+func (*Service) AggregateAttestation(_ context.Context,
 	_ *api.AggregateAttestationOpts,
 ) (
 	*api.Response[*phase0.Attestation],
diff --git a/mock/attestationdata.go b/mock/attestationdata.go
index c93d08f0..60af2756 100644
--- a/mock/attestationdata.go
+++ b/mock/attestationdata.go
@@ -21,7 +21,7 @@ import (
 )
 
 // AttestationData fetches the attestation data for the given slot and committee index.
-func (s *Service) AttestationData(_ context.Context,
+func (*Service) AttestationData(_ context.Context,
 	_ *api.AttestationDataOpts,
 ) (
 	*api.Response[*phase0.AttestationData],
diff --git a/mock/attestationpool.go b/mock/attestationpool.go
index 9eb70c51..5f35c7df 100644
--- a/mock/attestationpool.go
+++ b/mock/attestationpool.go
@@ -21,7 +21,7 @@ import (
 )
 
 // AttestationPool fetches the attestation pool for the given slot.
-func (s *Service) AttestationPool(_ context.Context,
+func (*Service) AttestationPool(_ context.Context,
 	_ *api.AttestationPoolOpts,
 ) (
 	*api.Response[[]*phase0.Attestation],
diff --git a/mock/attesterduties.go b/mock/attesterduties.go
index a0affcdb..e2150057 100644
--- a/mock/attesterduties.go
+++ b/mock/attesterduties.go
@@ -22,7 +22,7 @@ import (
 
 // AttesterDuties obtains attester duties.
 // If validatorIndicess is nil it will return all duties for the given epoch.
-func (s *Service) AttesterDuties(_ context.Context, opts *api.AttesterDutiesOpts) (*api.Response[[]*apiv1.AttesterDuty], error) {
+func (*Service) AttesterDuties(_ context.Context, opts *api.AttesterDutiesOpts) (*api.Response[[]*apiv1.AttesterDuty], error) {
 	data := make([]*apiv1.AttesterDuty, len(opts.Indices))
 	for i := range opts.Indices {
 		data[i] = &apiv1.AttesterDuty{
diff --git a/mock/beaconattesterdomain.go b/mock/beaconattesterdomain.go
index 0a0b42b6..e9133d5f 100644
--- a/mock/beaconattesterdomain.go
+++ b/mock/beaconattesterdomain.go
@@ -20,6 +20,6 @@ import (
 )
 
 // BeaconAttesterDomain provides the beacon attester domain.
-func (s *Service) BeaconAttesterDomain(_ context.Context) (spec.DomainType, error) {
+func (*Service) BeaconAttesterDomain(_ context.Context) (spec.DomainType, error) {
 	return spec.DomainType{0x01, 0x00, 0x00, 0x00}, nil
 }
diff --git a/mock/beaconblockheader.go b/mock/beaconblockheader.go
index 9d9ff498..fab8cbbc 100644
--- a/mock/beaconblockheader.go
+++ b/mock/beaconblockheader.go
@@ -22,7 +22,7 @@ import (
 )
 
 // BeaconBlockHeader provides the block header of a given block ID.
-func (s *Service) BeaconBlockHeader(_ context.Context,
+func (*Service) BeaconBlockHeader(_ context.Context,
 	_ *api.BeaconBlockHeaderOpts,
 ) (
 	*api.Response[*apiv1.BeaconBlockHeader],
diff --git a/mock/beaconblockroot.go b/mock/beaconblockroot.go
index 142e45ff..50b7c388 100644
--- a/mock/beaconblockroot.go
+++ b/mock/beaconblockroot.go
@@ -21,7 +21,7 @@ import (
 )
 
 // BeaconBlockRoot fetches a block's root given a block ID.
-func (s *Service) BeaconBlockRoot(_ context.Context,
+func (*Service) BeaconBlockRoot(_ context.Context,
 	_ *api.BeaconBlockRootOpts,
 ) (
 	*api.Response[*phase0.Root],
diff --git a/mock/beaconcommittees.go b/mock/beaconcommittees.go
index 14ae33d3..f9592ad9 100644
--- a/mock/beaconcommittees.go
+++ b/mock/beaconcommittees.go
@@ -21,7 +21,7 @@ import (
 )
 
 // BeaconCommittees fetches all beacon committees for the epoch at the given state.
-func (s *Service) BeaconCommittees(_ context.Context,
+func (*Service) BeaconCommittees(_ context.Context,
 	_ *api.BeaconCommitteesOpts,
 ) (
 	*api.Response[[]*apiv1.BeaconCommittee],
diff --git a/mock/beaconproposerdomain.go b/mock/beaconproposerdomain.go
index 93cd4a94..33447cbb 100644
--- a/mock/beaconproposerdomain.go
+++ b/mock/beaconproposerdomain.go
@@ -20,6 +20,6 @@ import (
 )
 
 // BeaconProposerDomain provides the beacon proposer domain.
-func (s *Service) BeaconProposerDomain(_ context.Context) (spec.DomainType, error) {
+func (*Service) BeaconProposerDomain(_ context.Context) (spec.DomainType, error) {
 	return spec.DomainType{0x00, 0x00, 0x00, 0x00}, nil
 }
diff --git a/mock/beaconstate.go b/mock/beaconstate.go
index f65db42c..54b9994a 100644
--- a/mock/beaconstate.go
+++ b/mock/beaconstate.go
@@ -22,7 +22,7 @@ import (
 )
 
 // BeaconState fetches a beacon state given a state ID.
-func (s *Service) BeaconState(_ context.Context, _ *api.BeaconStateOpts) (*api.Response[*spec.VersionedBeaconState], error) {
+func (*Service) BeaconState(_ context.Context, _ *api.BeaconStateOpts) (*api.Response[*spec.VersionedBeaconState], error) {
 	data := &spec.VersionedBeaconState{
 		Version: spec.DataVersionPhase0,
 		Phase0: &phase0.BeaconState{
diff --git a/mock/beaconstateroot.go b/mock/beaconstateroot.go
index 0a0c1f3d..85fda59d 100644
--- a/mock/beaconstateroot.go
+++ b/mock/beaconstateroot.go
@@ -21,7 +21,7 @@ import (
 )
 
 // BeaconStateRoot fetches a beacon state's root given a state ID.
-func (s *Service) BeaconStateRoot(_ context.Context, _ *api.BeaconStateRootOpts) (*api.Response[*phase0.Root], error) {
+func (*Service) BeaconStateRoot(_ context.Context, _ *api.BeaconStateRootOpts) (*api.Response[*phase0.Root], error) {
 	data := phase0.Root{}
 
 	return &api.Response[*phase0.Root]{
diff --git a/mock/blindedproposal.go b/mock/blindedproposal.go
index bd66eeec..d62c28cc 100644
--- a/mock/blindedproposal.go
+++ b/mock/blindedproposal.go
@@ -24,7 +24,7 @@ import (
 )
 
 // BlindedProposal fetches a blinded proposal for signing.
-func (s *Service) BlindedProposal(_ context.Context,
+func (*Service) BlindedProposal(_ context.Context,
 	opts *api.BlindedProposalOpts,
 ) (
 	*api.Response[*api.VersionedBlindedProposal],
@@ -97,11 +97,11 @@ func (s *Service) BlindedProposal(_ context.Context,
 				},
 			},
 			Graffiti:          opts.Graffiti,
-			ProposerSlashings: []*phase0.ProposerSlashing{},
-			AttesterSlashings: []*phase0.AttesterSlashing{},
+			ProposerSlashings: make([]*phase0.ProposerSlashing, 0),
+			AttesterSlashings: make([]*phase0.AttesterSlashing, 0),
 			Attestations:      attestations,
-			Deposits:          []*phase0.Deposit{},
-			VoluntaryExits:    []*phase0.SignedVoluntaryExit{},
+			Deposits:          make([]*phase0.Deposit, 0),
+			VoluntaryExits:    make([]*phase0.SignedVoluntaryExit, 0),
 		},
 	}
 
diff --git a/mock/depositcontract.go b/mock/depositcontract.go
index dcb4746a..9c73e2e0 100644
--- a/mock/depositcontract.go
+++ b/mock/depositcontract.go
@@ -21,7 +21,7 @@ import (
 )
 
 // DepositContract provides details of the execution layer deposit contract for the chain.
-func (s *Service) DepositContract(_ context.Context, _ *api.DepositContractOpts) (*api.Response[*apiv1.DepositContract], error) {
+func (*Service) DepositContract(_ context.Context, _ *api.DepositContractOpts) (*api.Response[*apiv1.DepositContract], error) {
 	return &api.Response[*apiv1.DepositContract]{
 		Data:     &apiv1.DepositContract{},
 		Metadata: make(map[string]any),
diff --git a/mock/depositdomain.go b/mock/depositdomain.go
index 369d607a..94edbb66 100644
--- a/mock/depositdomain.go
+++ b/mock/depositdomain.go
@@ -20,6 +20,6 @@ import (
 )
 
 // DepositDomain provides the deposit domain.
-func (s *Service) DepositDomain(_ context.Context) (spec.DomainType, error) {
+func (*Service) DepositDomain(_ context.Context) (spec.DomainType, error) {
 	return spec.DomainType{0x03, 0x00, 0x00, 0x00}, nil
 }
diff --git a/mock/events.go b/mock/events.go
index a16750b1..37d13f18 100644
--- a/mock/events.go
+++ b/mock/events.go
@@ -20,6 +20,6 @@ import (
 )
 
 // Events feeds requested events with the given topics to the supplied handler.
-func (s *Service) Events(_ context.Context, _ []string, _ client.EventHandlerFunc) error {
+func (*Service) Events(_ context.Context, _ []string, _ client.EventHandlerFunc) error {
 	return nil
 }
diff --git a/mock/farfutureepoch.go b/mock/farfutureepoch.go
index 3a43a9a3..da1057f8 100644
--- a/mock/farfutureepoch.go
+++ b/mock/farfutureepoch.go
@@ -20,6 +20,6 @@ import (
 )
 
 // FarFutureEpoch provides the values for FAR_FUTURE_EOPCH of the chain.
-func (s *Service) FarFutureEpoch(_ context.Context) (spec.Epoch, error) {
+func (*Service) FarFutureEpoch(_ context.Context) (spec.Epoch, error) {
 	return spec.Epoch(0xffffffffffffffff), nil
 }
diff --git a/mock/finality.go b/mock/finality.go
index 812f054f..edd0255e 100644
--- a/mock/finality.go
+++ b/mock/finality.go
@@ -22,7 +22,7 @@ import (
 )
 
 // Finality provides the finality given a state ID.
-func (s *Service) Finality(_ context.Context, _ *api.FinalityOpts) (*api.Response[*apiv1.Finality], error) {
+func (*Service) Finality(_ context.Context, _ *api.FinalityOpts) (*api.Response[*apiv1.Finality], error) {
 	return &api.Response[*apiv1.Finality]{
 		Data: &apiv1.Finality{
 			Finalized: &phase0.Checkpoint{
diff --git a/mock/forkschedule.go b/mock/forkschedule.go
index 32bef4bf..acbf3d40 100644
--- a/mock/forkschedule.go
+++ b/mock/forkschedule.go
@@ -21,7 +21,7 @@ import (
 )
 
 // ForkSchedule provides details of past and future changes in the chain's fork version.
-func (s *Service) ForkSchedule(_ context.Context, _ *api.ForkScheduleOpts) (*api.Response[[]*spec.Fork], error) {
+func (*Service) ForkSchedule(_ context.Context, _ *api.ForkScheduleOpts) (*api.Response[[]*spec.Fork], error) {
 	data := []*spec.Fork{
 		{
 			PreviousVersion: spec.Version{0x01, 0x02, 0x03, 0x04},
diff --git a/mock/nodepeers.go b/mock/nodepeers.go
index 42cf85b4..5f7c1172 100644
--- a/mock/nodepeers.go
+++ b/mock/nodepeers.go
@@ -21,7 +21,7 @@ import (
 )
 
 // NodePeers provides the peers of the node.
-func (s *Service) NodePeers(_ context.Context, _ *api.NodePeersOpts) (*api.Response[[]*apiv1.Peer], error) {
+func (*Service) NodePeers(_ context.Context, _ *api.NodePeersOpts) (*api.Response[[]*apiv1.Peer], error) {
 	return &api.Response[[]*apiv1.Peer]{
 		Data: []*apiv1.Peer{{
 			PeerID:             "MOCK16Uiu2HAm7ukVy4XugqVShYbLih4H2jBJjYevevznBZaHsmd1FM96",
diff --git a/mock/proposal.go b/mock/proposal.go
index fb679a0a..b70e17fb 100644
--- a/mock/proposal.go
+++ b/mock/proposal.go
@@ -23,7 +23,7 @@ import (
 )
 
 // Proposal fetches a proposal for signing.
-func (s *Service) Proposal(_ context.Context,
+func (*Service) Proposal(_ context.Context,
 	opts *api.ProposalOpts,
 ) (
 	*api.Response[*api.VersionedProposal], error,
@@ -95,11 +95,11 @@ func (s *Service) Proposal(_ context.Context,
 				},
 			},
 			Graffiti:          opts.Graffiti,
-			ProposerSlashings: []*phase0.ProposerSlashing{},
-			AttesterSlashings: []*phase0.AttesterSlashing{},
+			ProposerSlashings: make([]*phase0.ProposerSlashing, 0),
+			AttesterSlashings: make([]*phase0.AttesterSlashing, 0),
 			Attestations:      attestations,
-			Deposits:          []*phase0.Deposit{},
-			VoluntaryExits:    []*phase0.SignedVoluntaryExit{},
+			Deposits:          make([]*phase0.Deposit, 0),
+			VoluntaryExits:    make([]*phase0.SignedVoluntaryExit, 0),
 		},
 	}
 
diff --git a/mock/proposerduties.go b/mock/proposerduties.go
index 7a3f6db6..cdea0cc1 100644
--- a/mock/proposerduties.go
+++ b/mock/proposerduties.go
@@ -22,7 +22,7 @@ import (
 
 // ProposerDuties obtains proposer duties for the given epoch.
 // If validatorIndices is empty all duties are returned, otherwise only matching duties are returned.
-func (s *Service) ProposerDuties(_ context.Context, opts *api.ProposerDutiesOpts) (*api.Response[[]*apiv1.ProposerDuty], error) {
+func (*Service) ProposerDuties(_ context.Context, opts *api.ProposerDutiesOpts) (*api.Response[[]*apiv1.ProposerDuty], error) {
 	data := make([]*apiv1.ProposerDuty, len(opts.Indices))
 	for i := range opts.Indices {
 		data[i] = &apiv1.ProposerDuty{
diff --git a/mock/randaodomain.go b/mock/randaodomain.go
index 86a9937a..315a3093 100644
--- a/mock/randaodomain.go
+++ b/mock/randaodomain.go
@@ -20,6 +20,6 @@ import (
 )
 
 // RANDAODomain provides the RANDAO domain.
-func (s *Service) RANDAODomain(_ context.Context) (spec.DomainType, error) {
+func (*Service) RANDAODomain(_ context.Context) (spec.DomainType, error) {
 	return spec.DomainType{0x02, 0x00, 0x00, 0x00}, nil
 }
diff --git a/mock/selectionproofdomain.go b/mock/selectionproofdomain.go
index 3d62a3eb..6d9d561f 100644
--- a/mock/selectionproofdomain.go
+++ b/mock/selectionproofdomain.go
@@ -20,6 +20,6 @@ import (
 )
 
 // SelectionProofDomain provides the selection proof domain.
-func (s *Service) SelectionProofDomain(_ context.Context) (spec.DomainType, error) {
+func (*Service) SelectionProofDomain(_ context.Context) (spec.DomainType, error) {
 	return spec.DomainType{0x05, 0x00, 0x00, 0x00}, nil
 }
diff --git a/mock/service.go b/mock/service.go
index a94efa09..6662a1f9 100644
--- a/mock/service.go
+++ b/mock/service.go
@@ -76,7 +76,7 @@ func New(ctx context.Context, params ...Parameter) (*Service, error) {
 	}
 
 	// Close the service on context done.
-	go func(s *Service) {
+	go func(*Service) {
 		<-ctx.Done()
 		log.Trace().Msg("Context done; closing connection")
 		s.close()
@@ -105,7 +105,7 @@ func (s *Service) fetchStaticValues(ctx context.Context) error {
 }
 
 // Name provides the name of the service.
-func (s *Service) Name() string {
+func (*Service) Name() string {
 	return "Mock"
 }
 
@@ -115,7 +115,7 @@ func (s *Service) Address() string {
 }
 
 // IsActive returns true if the client is active.
-func (s *Service) IsActive() bool {
+func (*Service) IsActive() bool {
 	return true
 }
 
@@ -125,5 +125,5 @@ func (s *Service) IsSynced() bool {
 }
 
 // close closes the service, freeing up resources.
-func (s *Service) close() {
+func (*Service) close() {
 }
diff --git a/mock/signedbeaconblock.go b/mock/signedbeaconblock.go
index b653a189..5dc997c1 100644
--- a/mock/signedbeaconblock.go
+++ b/mock/signedbeaconblock.go
@@ -22,7 +22,7 @@ import (
 )
 
 // SignedBeaconBlock fetches a signed beacon block given a block ID.
-func (s *Service) SignedBeaconBlock(_ context.Context, _ *api.SignedBeaconBlockOpts) (*api.Response[*spec.VersionedSignedBeaconBlock], error) {
+func (*Service) SignedBeaconBlock(_ context.Context, _ *api.SignedBeaconBlockOpts) (*api.Response[*spec.VersionedSignedBeaconBlock], error) {
 	return &api.Response[*spec.VersionedSignedBeaconBlock]{
 		Data: &spec.VersionedSignedBeaconBlock{
 			Version: spec.DataVersionPhase0,
diff --git a/mock/slotduration.go b/mock/slotduration.go
index 7ac46a29..8a4350a6 100644
--- a/mock/slotduration.go
+++ b/mock/slotduration.go
@@ -19,6 +19,6 @@ import (
 )
 
 // SlotDuration provides the duration of a slot of the chain.
-func (s *Service) SlotDuration(_ context.Context) (time.Duration, error) {
+func (*Service) SlotDuration(_ context.Context) (time.Duration, error) {
 	return 12 * time.Second, nil
 }
diff --git a/mock/slotsperepoch.go b/mock/slotsperepoch.go
index 736729fc..f9f8730d 100644
--- a/mock/slotsperepoch.go
+++ b/mock/slotsperepoch.go
@@ -18,6 +18,6 @@ import (
 )
 
 // SlotsPerEpoch provides the slots per epoch of the chain.
-func (s *Service) SlotsPerEpoch(_ context.Context) (uint64, error) {
+func (*Service) SlotsPerEpoch(_ context.Context) (uint64, error) {
 	return 32, nil
 }
diff --git a/mock/spec.go b/mock/spec.go
index e776565a..f83e3d0c 100644
--- a/mock/spec.go
+++ b/mock/spec.go
@@ -22,7 +22,7 @@ import (
 
 // Spec provides the spec information of the chain.
 // This returns various useful values.
-func (s *Service) Spec(_ context.Context, _ *api.SpecOpts) (*api.Response[map[string]any], error) {
+func (*Service) Spec(_ context.Context, _ *api.SpecOpts) (*api.Response[map[string]any], error) {
 	data := map[string]any{
 		"SECONDS_PER_SLOT": 12 * time.Second,
 		"SLOTS_PER_EPOCH":  uint64(32),
diff --git a/mock/submitaggregateattestations.go b/mock/submitaggregateattestations.go
index 0b62c959..8e20adba 100644
--- a/mock/submitaggregateattestations.go
+++ b/mock/submitaggregateattestations.go
@@ -20,6 +20,6 @@ import (
 )
 
 // SubmitAggregateAttestations submits aggregate attestations.
-func (s *Service) SubmitAggregateAttestations(_ context.Context, _ []*spec.SignedAggregateAndProof) error {
+func (*Service) SubmitAggregateAttestations(_ context.Context, _ []*spec.SignedAggregateAndProof) error {
 	return nil
 }
diff --git a/mock/submitattestations.go b/mock/submitattestations.go
index 255fd5f9..699def7b 100644
--- a/mock/submitattestations.go
+++ b/mock/submitattestations.go
@@ -20,6 +20,6 @@ import (
 )
 
 // SubmitAttestations submits attestations.
-func (s *Service) SubmitAttestations(_ context.Context, _ []*spec.Attestation) error {
+func (*Service) SubmitAttestations(_ context.Context, _ []*spec.Attestation) error {
 	return nil
 }
diff --git a/mock/submitattesterslashing.go b/mock/submitattesterslashing.go
index 849b999a..fe418bff 100644
--- a/mock/submitattesterslashing.go
+++ b/mock/submitattesterslashing.go
@@ -20,6 +20,6 @@ import (
 )
 
 // SubmitAttesterSlashing submits a proposal slashing.
-func (s *Service) SubmitAttesterSlashing(_ context.Context, _ *phase0.AttesterSlashing) error {
+func (*Service) SubmitAttesterSlashing(_ context.Context, _ *phase0.AttesterSlashing) error {
 	return nil
 }
diff --git a/mock/submitbeaconblock.go b/mock/submitbeaconblock.go
index ab8d11e6..7882fb72 100644
--- a/mock/submitbeaconblock.go
+++ b/mock/submitbeaconblock.go
@@ -16,10 +16,10 @@ package mock
 import (
 	"context"
 
-	spec "github.com/attestantio/go-eth2-client/spec"
+	"github.com/attestantio/go-eth2-client/spec"
 )
 
 // SubmitBeaconBlock submits a beacon block.
-func (s *Service) SubmitBeaconBlock(_ context.Context, _ *spec.VersionedSignedBeaconBlock) error {
+func (*Service) SubmitBeaconBlock(_ context.Context, _ *spec.VersionedSignedBeaconBlock) error {
 	return nil
 }
diff --git a/mock/submitbeaconcommitteesubscriptions.go b/mock/submitbeaconcommitteesubscriptions.go
index 81d21304..63d3aba0 100644
--- a/mock/submitbeaconcommitteesubscriptions.go
+++ b/mock/submitbeaconcommitteesubscriptions.go
@@ -20,6 +20,6 @@ import (
 )
 
 // SubmitBeaconCommitteeSubscriptions subscribes to beacon committees.
-func (s *Service) SubmitBeaconCommitteeSubscriptions(_ context.Context, _ []*api.BeaconCommitteeSubscription) error {
+func (*Service) SubmitBeaconCommitteeSubscriptions(_ context.Context, _ []*api.BeaconCommitteeSubscription) error {
 	return nil
 }
diff --git a/mock/submitblindedbeaconblock.go b/mock/submitblindedbeaconblock.go
index c26486cb..97e40676 100644
--- a/mock/submitblindedbeaconblock.go
+++ b/mock/submitblindedbeaconblock.go
@@ -20,6 +20,6 @@ import (
 )
 
 // SubmitBlindedBeaconBlock submits a blinded beacon block.
-func (s *Service) SubmitBlindedBeaconBlock(_ context.Context, _ *api.VersionedSignedBlindedBeaconBlock) error {
+func (*Service) SubmitBlindedBeaconBlock(_ context.Context, _ *api.VersionedSignedBlindedBeaconBlock) error {
 	return nil
 }
diff --git a/mock/submitblstoexecutionchange.go b/mock/submitblstoexecutionchange.go
index 73f9289d..8cd2b8ef 100644
--- a/mock/submitblstoexecutionchange.go
+++ b/mock/submitblstoexecutionchange.go
@@ -20,6 +20,6 @@ import (
 )
 
 // SubmitBLSToExecutionChange submits a BLS to execution address change operation.
-func (s *Service) SubmitBLSToExecutionChange(_ context.Context, _ *capella.SignedBLSToExecutionChange) error {
+func (*Service) SubmitBLSToExecutionChange(_ context.Context, _ *capella.SignedBLSToExecutionChange) error {
 	return nil
 }
diff --git a/mock/submitproposal.go b/mock/submitproposal.go
index 700e532d..d1b0f067 100644
--- a/mock/submitproposal.go
+++ b/mock/submitproposal.go
@@ -20,6 +20,6 @@ import (
 )
 
 // SubmitProposal submits a proposal.
-func (s *Service) SubmitProposal(_ context.Context, _ *api.VersionedSignedProposal) error {
+func (*Service) SubmitProposal(_ context.Context, _ *api.VersionedSignedProposal) error {
 	return nil
 }
diff --git a/mock/submitproposalpreparations.go b/mock/submitproposalpreparations.go
index b6db8859..28648afa 100644
--- a/mock/submitproposalpreparations.go
+++ b/mock/submitproposalpreparations.go
@@ -21,6 +21,6 @@ import (
 
 // SubmitProposalPreparations provides the beacon node with information required if a proposal for the given validators
 // shows up in the next epoch.
-func (s *Service) SubmitProposalPreparations(_ context.Context, _ []*apiv1.ProposalPreparation) error {
+func (*Service) SubmitProposalPreparations(_ context.Context, _ []*apiv1.ProposalPreparation) error {
 	return nil
 }
diff --git a/mock/submitproposalslashing.go b/mock/submitproposalslashing.go
index bf821caf..5a1cd501 100644
--- a/mock/submitproposalslashing.go
+++ b/mock/submitproposalslashing.go
@@ -20,6 +20,6 @@ import (
 )
 
 // SubmitProposalSlashing submits a proposal slashing.
-func (s *Service) SubmitProposalSlashing(_ context.Context, _ *phase0.ProposerSlashing) error {
+func (*Service) SubmitProposalSlashing(_ context.Context, _ *phase0.ProposerSlashing) error {
 	return nil
 }
diff --git a/mock/submitsynccommitteecontributions.go b/mock/submitsynccommitteecontributions.go
index e4cc9cc2..d17b1962 100644
--- a/mock/submitsynccommitteecontributions.go
+++ b/mock/submitsynccommitteecontributions.go
@@ -20,6 +20,6 @@ import (
 )
 
 // SubmitSyncCommitteeContributions submits sync committee contributions.
-func (s *Service) SubmitSyncCommitteeContributions(_ context.Context, _ []*altair.SignedContributionAndProof) error {
+func (*Service) SubmitSyncCommitteeContributions(_ context.Context, _ []*altair.SignedContributionAndProof) error {
 	return nil
 }
diff --git a/mock/submitsynccommitteemessages.go b/mock/submitsynccommitteemessages.go
index 8915d845..d3174758 100644
--- a/mock/submitsynccommitteemessages.go
+++ b/mock/submitsynccommitteemessages.go
@@ -20,6 +20,6 @@ import (
 )
 
 // SubmitSyncCommitteeMessages submits sync committee messages.
-func (s *Service) SubmitSyncCommitteeMessages(_ context.Context, _ []*altair.SyncCommitteeMessage) error {
+func (*Service) SubmitSyncCommitteeMessages(_ context.Context, _ []*altair.SyncCommitteeMessage) error {
 	return nil
 }
diff --git a/mock/submitsynccommitteesubscriptions.go b/mock/submitsynccommitteesubscriptions.go
index 47ce291d..381a829e 100644
--- a/mock/submitsynccommitteesubscriptions.go
+++ b/mock/submitsynccommitteesubscriptions.go
@@ -20,6 +20,6 @@ import (
 )
 
 // SubmitSyncCommitteeSubscriptions subscribes to sync committees.
-func (s *Service) SubmitSyncCommitteeSubscriptions(_ context.Context, _ []*api.SyncCommitteeSubscription) error {
+func (*Service) SubmitSyncCommitteeSubscriptions(_ context.Context, _ []*api.SyncCommitteeSubscription) error {
 	return nil
 }
diff --git a/mock/submitvalidatorregistration.go b/mock/submitvalidatorregistration.go
index c7def11f..7eadf8aa 100644
--- a/mock/submitvalidatorregistration.go
+++ b/mock/submitvalidatorregistration.go
@@ -20,6 +20,6 @@ import (
 )
 
 // SubmitValidatorRegistrations submits a validator registration.
-func (s *Service) SubmitValidatorRegistrations(_ context.Context, _ []*api.VersionedSignedValidatorRegistration) error {
+func (*Service) SubmitValidatorRegistrations(_ context.Context, _ []*api.VersionedSignedValidatorRegistration) error {
 	return nil
 }
diff --git a/mock/submitvoluntaryexit.go b/mock/submitvoluntaryexit.go
index 56d71c8a..d195a90a 100644
--- a/mock/submitvoluntaryexit.go
+++ b/mock/submitvoluntaryexit.go
@@ -20,6 +20,6 @@ import (
 )
 
 // SubmitVoluntaryExit submits a voluntary exit.
-func (s *Service) SubmitVoluntaryExit(_ context.Context, _ *spec.SignedVoluntaryExit) error {
+func (*Service) SubmitVoluntaryExit(_ context.Context, _ *spec.SignedVoluntaryExit) error {
 	return nil
 }
diff --git a/mock/synccommittee.go b/mock/synccommittee.go
index 2e9d8d6f..da68438d 100644
--- a/mock/synccommittee.go
+++ b/mock/synccommittee.go
@@ -21,7 +21,7 @@ import (
 )
 
 // SyncCommittee fetches the sync committee for the given state.
-func (s *Service) SyncCommittee(_ context.Context, _ *api.SyncCommitteeOpts) (*api.Response[*apiv1.SyncCommittee], error) {
+func (*Service) SyncCommittee(_ context.Context, _ *api.SyncCommitteeOpts) (*api.Response[*apiv1.SyncCommittee], error) {
 	return &api.Response[*apiv1.SyncCommittee]{
 		Data:     &apiv1.SyncCommittee{},
 		Metadata: make(map[string]any),
diff --git a/mock/synccommitteecontributionprovider.go b/mock/synccommitteecontributionprovider.go
index ae9814e1..e6dbbc41 100644
--- a/mock/synccommitteecontributionprovider.go
+++ b/mock/synccommitteecontributionprovider.go
@@ -23,7 +23,7 @@ import (
 )
 
 // SyncCommitteeContribution provides a sync committee contribution.
-func (s *Service) SyncCommitteeContribution(_ context.Context, _ *api.SyncCommitteeContributionOpts) (*api.Response[*altair.SyncCommitteeContribution], error) {
+func (*Service) SyncCommitteeContribution(_ context.Context, _ *api.SyncCommitteeContributionOpts) (*api.Response[*altair.SyncCommitteeContribution], error) {
 	return &api.Response[*altair.SyncCommitteeContribution]{
 		Data: &altair.SyncCommitteeContribution{
 			Slot: 5,
diff --git a/mock/synccommitteeduties.go b/mock/synccommitteeduties.go
index 53d31efa..7988f390 100644
--- a/mock/synccommitteeduties.go
+++ b/mock/synccommitteeduties.go
@@ -21,7 +21,7 @@ import (
 )
 
 // SyncCommitteeDuties obtains sync committee duties.
-func (s *Service) SyncCommitteeDuties(_ context.Context, opts *api.SyncCommitteeDutiesOpts) (*api.Response[[]*apiv1.SyncCommitteeDuty], error) {
+func (*Service) SyncCommitteeDuties(_ context.Context, opts *api.SyncCommitteeDutiesOpts) (*api.Response[[]*apiv1.SyncCommitteeDuty], error) {
 	data := make([]*apiv1.SyncCommitteeDuty, len(opts.Indices))
 	for i := range opts.Indices {
 		data[i] = &apiv1.SyncCommitteeDuty{
diff --git a/mock/targetaggregatorspercommittee.go b/mock/targetaggregatorspercommittee.go
index 4cc0f9aa..4f4113a5 100644
--- a/mock/targetaggregatorspercommittee.go
+++ b/mock/targetaggregatorspercommittee.go
@@ -18,6 +18,6 @@ import (
 )
 
 // TargetAggregatorsPerCommittee provides the target number of aggregators for each attestation committee.
-func (s *Service) TargetAggregatorsPerCommittee(_ context.Context) (uint64, error) {
+func (*Service) TargetAggregatorsPerCommittee(_ context.Context) (uint64, error) {
 	return 4, nil
 }
diff --git a/mock/validatorbalances.go b/mock/validatorbalances.go
index 719efb8a..d2658613 100644
--- a/mock/validatorbalances.go
+++ b/mock/validatorbalances.go
@@ -24,7 +24,7 @@ import (
 // stateID can be a slot number or state root, or one of the special values "genesis", "head", "justified" or "finalized".
 // validatorIndices is a list of validator indices to restrict the returned values.  If no validators are supplied no filter
 // will be applied.
-func (s *Service) ValidatorBalances(_ context.Context, _ *api.ValidatorBalancesOpts) (*api.Response[map[phase0.ValidatorIndex]phase0.Gwei], error) {
+func (*Service) ValidatorBalances(_ context.Context, _ *api.ValidatorBalancesOpts) (*api.Response[map[phase0.ValidatorIndex]phase0.Gwei], error) {
 	return &api.Response[map[phase0.ValidatorIndex]phase0.Gwei]{
 		Data:     map[phase0.ValidatorIndex]phase0.Gwei{},
 		Metadata: make(map[string]any),
diff --git a/mock/validators.go b/mock/validators.go
index 9c75f701..e8bb30c9 100644
--- a/mock/validators.go
+++ b/mock/validators.go
@@ -22,7 +22,7 @@ import (
 )
 
 // Validators provides the validators, with their balance and status, for a given state.
-func (s *Service) Validators(_ context.Context, _ *api.ValidatorsOpts) (*api.Response[map[phase0.ValidatorIndex]*apiv1.Validator], error) {
+func (*Service) Validators(_ context.Context, _ *api.ValidatorsOpts) (*api.Response[map[phase0.ValidatorIndex]*apiv1.Validator], error) {
 	return &api.Response[map[phase0.ValidatorIndex]*apiv1.Validator]{
 		Data:     map[phase0.ValidatorIndex]*apiv1.Validator{},
 		Metadata: make(map[string]any),
diff --git a/mock/voluntaryexitdomain.go b/mock/voluntaryexitdomain.go
index 90c94b41..cbbc508b 100644
--- a/mock/voluntaryexitdomain.go
+++ b/mock/voluntaryexitdomain.go
@@ -20,6 +20,6 @@ import (
 )
 
 // VoluntaryExitDomain provides the voluntary exit domain.
-func (s *Service) VoluntaryExitDomain(_ context.Context) (spec.DomainType, error) {
+func (*Service) VoluntaryExitDomain(_ context.Context) (spec.DomainType, error) {
 	return spec.DomainType{0x04, 0x00, 0x00, 0x00}, nil
 }
diff --git a/mock/voluntaryexitpool.go b/mock/voluntaryexitpool.go
index 22c1a313..dff81050 100644
--- a/mock/voluntaryexitpool.go
+++ b/mock/voluntaryexitpool.go
@@ -21,7 +21,7 @@ import (
 )
 
 // VoluntaryExitPool fetches the voluntary exit pool.
-func (s *Service) VoluntaryExitPool(_ context.Context, _ *api.VoluntaryExitPoolOpts) (*api.Response[[]*spec.SignedVoluntaryExit], error) {
+func (*Service) VoluntaryExitPool(_ context.Context, _ *api.VoluntaryExitPoolOpts) (*api.Response[[]*spec.SignedVoluntaryExit], error) {
 	res := make([]*spec.SignedVoluntaryExit, 5)
 	for i := 0; i < 5; i++ {
 		res[i] = &spec.SignedVoluntaryExit{
diff --git a/multi/aggregateattestation.go b/multi/aggregateattestation.go
index 0f6d3c20..ff0f7f8d 100644
--- a/multi/aggregateattestation.go
+++ b/multi/aggregateattestation.go
@@ -28,7 +28,7 @@ func (s *Service) AggregateAttestation(ctx context.Context,
 	*api.Response[*phase0.Attestation],
 	error,
 ) {
-	res, err := s.doCall(ctx, func(ctx context.Context, client consensusclient.Service) (interface{}, error) {
+	res, err := s.doCall(ctx, func(ctx context.Context, client consensusclient.Service) (any, error) {
 		aggregate, err := client.(consensusclient.AggregateAttestationProvider).AggregateAttestation(ctx, opts)
 		if err != nil {
 			return nil, err
@@ -40,5 +40,10 @@ func (s *Service) AggregateAttestation(ctx context.Context,
 		return nil, err
 	}
 
-	return res.(*api.Response[*phase0.Attestation]), nil
+	response, isResponse := res.(*api.Response[*phase0.Attestation])
+	if !isResponse {
+		return nil, ErrIncorrectType
+	}
+
+	return response, nil
 }
diff --git a/multi/attestationdata.go b/multi/attestationdata.go
index ce9f627e..0c825396 100644
--- a/multi/attestationdata.go
+++ b/multi/attestationdata.go
@@ -28,7 +28,7 @@ func (s *Service) AttestationData(ctx context.Context,
 	*api.Response[*phase0.AttestationData],
 	error,
 ) {
-	res, err := s.doCall(ctx, func(ctx context.Context, client consensusclient.Service) (interface{}, error) {
+	res, err := s.doCall(ctx, func(ctx context.Context, client consensusclient.Service) (any, error) {
 		attestationData, err := client.(consensusclient.AttestationDataProvider).AttestationData(ctx, opts)
 		if err != nil {
 			return nil, err
@@ -40,5 +40,10 @@ func (s *Service) AttestationData(ctx context.Context,
 		return nil, err
 	}
 
-	return res.(*api.Response[*phase0.AttestationData]), nil
+	response, isResponse := res.(*api.Response[*phase0.AttestationData])
+	if !isResponse {
+		return nil, ErrIncorrectType
+	}
+
+	return response, nil
 }
diff --git a/multi/attestationpool.go b/multi/attestationpool.go
index 46bc2f3f..0228fbba 100644
--- a/multi/attestationpool.go
+++ b/multi/attestationpool.go
@@ -28,7 +28,7 @@ func (s *Service) AttestationPool(ctx context.Context,
 	*api.Response[[]*phase0.Attestation],
 	error,
 ) {
-	res, err := s.doCall(ctx, func(ctx context.Context, client consensusclient.Service) (interface{}, error) {
+	res, err := s.doCall(ctx, func(ctx context.Context, client consensusclient.Service) (any, error) {
 		attestationPool, err := client.(consensusclient.AttestationPoolProvider).AttestationPool(ctx, opts)
 		if err != nil {
 			return nil, err
@@ -40,5 +40,10 @@ func (s *Service) AttestationPool(ctx context.Context,
 		return nil, err
 	}
 
-	return res.(*api.Response[[]*phase0.Attestation]), nil
+	response, isResponse := res.(*api.Response[[]*phase0.Attestation])
+	if !isResponse {
+		return nil, ErrIncorrectType
+	}
+
+	return response, nil
 }
diff --git a/multi/attesterduties.go b/multi/attesterduties.go
index 3483af80..de0d0ce1 100644
--- a/multi/attesterduties.go
+++ b/multi/attesterduties.go
@@ -29,7 +29,7 @@ func (s *Service) AttesterDuties(ctx context.Context,
 	*api.Response[[]*apiv1.AttesterDuty],
 	error,
 ) {
-	res, err := s.doCall(ctx, func(ctx context.Context, client consensusclient.Service) (interface{}, error) {
+	res, err := s.doCall(ctx, func(ctx context.Context, client consensusclient.Service) (any, error) {
 		block, err := client.(consensusclient.AttesterDutiesProvider).AttesterDuties(ctx, opts)
 		if err != nil {
 			return nil, err
@@ -41,5 +41,10 @@ func (s *Service) AttesterDuties(ctx context.Context,
 		return nil, err
 	}
 
-	return res.(*api.Response[[]*apiv1.AttesterDuty]), nil
+	response, isResponse := res.(*api.Response[[]*apiv1.AttesterDuty])
+	if !isResponse {
+		return nil, ErrIncorrectType
+	}
+
+	return response, nil
 }
diff --git a/multi/beaconblockheader.go b/multi/beaconblockheader.go
index ceb255bf..1ebb8844 100644
--- a/multi/beaconblockheader.go
+++ b/multi/beaconblockheader.go
@@ -28,7 +28,7 @@ func (s *Service) BeaconBlockHeader(ctx context.Context,
 	*api.Response[*apiv1.BeaconBlockHeader],
 	error,
 ) {
-	res, err := s.doCall(ctx, func(ctx context.Context, client consensusclient.Service) (interface{}, error) {
+	res, err := s.doCall(ctx, func(ctx context.Context, client consensusclient.Service) (any, error) {
 		beaconBlockHeader, err := client.(consensusclient.BeaconBlockHeadersProvider).BeaconBlockHeader(ctx, opts)
 		if err != nil {
 			return nil, err
@@ -40,5 +40,10 @@ func (s *Service) BeaconBlockHeader(ctx context.Context,
 		return nil, err
 	}
 
-	return res.(*api.Response[*apiv1.BeaconBlockHeader]), nil
+	response, isResponse := res.(*api.Response[*apiv1.BeaconBlockHeader])
+	if !isResponse {
+		return nil, ErrIncorrectType
+	}
+
+	return response, nil
 }
diff --git a/multi/beaconblockroot.go b/multi/beaconblockroot.go
index 98bdbb1c..f3a2e32f 100644
--- a/multi/beaconblockroot.go
+++ b/multi/beaconblockroot.go
@@ -28,7 +28,7 @@ func (s *Service) BeaconBlockRoot(ctx context.Context,
 	*api.Response[*phase0.Root],
 	error,
 ) {
-	res, err := s.doCall(ctx, func(ctx context.Context, client consensusclient.Service) (interface{}, error) {
+	res, err := s.doCall(ctx, func(ctx context.Context, client consensusclient.Service) (any, error) {
 		root, err := client.(consensusclient.BeaconBlockRootProvider).BeaconBlockRoot(ctx, opts)
 		if err != nil {
 			return nil, err
@@ -40,5 +40,10 @@ func (s *Service) BeaconBlockRoot(ctx context.Context,
 		return nil, err
 	}
 
-	return res.(*api.Response[*phase0.Root]), nil
+	response, isResponse := res.(*api.Response[*phase0.Root])
+	if !isResponse {
+		return nil, ErrIncorrectType
+	}
+
+	return response, nil
 }
diff --git a/multi/beaconcommittees.go b/multi/beaconcommittees.go
index d6b1eae0..ad7145b2 100644
--- a/multi/beaconcommittees.go
+++ b/multi/beaconcommittees.go
@@ -28,7 +28,7 @@ func (s *Service) BeaconCommittees(ctx context.Context,
 	*api.Response[[]*apiv1.BeaconCommittee],
 	error,
 ) {
-	res, err := s.doCall(ctx, func(ctx context.Context, client consensusclient.Service) (interface{}, error) {
+	res, err := s.doCall(ctx, func(ctx context.Context, client consensusclient.Service) (any, error) {
 		beaconCommittees, err := client.(consensusclient.BeaconCommitteesProvider).BeaconCommittees(ctx, opts)
 		if err != nil {
 			return nil, err
@@ -40,5 +40,10 @@ func (s *Service) BeaconCommittees(ctx context.Context,
 		return nil, err
 	}
 
-	return res.(*api.Response[[]*apiv1.BeaconCommittee]), nil
+	response, isResponse := res.(*api.Response[[]*apiv1.BeaconCommittee])
+	if !isResponse {
+		return nil, ErrIncorrectType
+	}
+
+	return response, nil
 }
diff --git a/multi/beaconstate.go b/multi/beaconstate.go
index 91c718bb..b2bd8150 100644
--- a/multi/beaconstate.go
+++ b/multi/beaconstate.go
@@ -23,7 +23,7 @@ import (
 
 // BeaconState fetches a beacon state.
 func (s *Service) BeaconState(ctx context.Context, opts *api.BeaconStateOpts) (*api.Response[*spec.VersionedBeaconState], error) {
-	res, err := s.doCall(ctx, func(ctx context.Context, client consensusclient.Service) (interface{}, error) {
+	res, err := s.doCall(ctx, func(ctx context.Context, client consensusclient.Service) (any, error) {
 		beaconState, err := client.(consensusclient.BeaconStateProvider).BeaconState(ctx, opts)
 		if err != nil {
 			return nil, err
@@ -35,5 +35,10 @@ func (s *Service) BeaconState(ctx context.Context, opts *api.BeaconStateOpts) (*
 		return nil, err
 	}
 
-	return res.(*api.Response[*spec.VersionedBeaconState]), nil
+	response, isResponse := res.(*api.Response[*spec.VersionedBeaconState])
+	if !isResponse {
+		return nil, ErrIncorrectType
+	}
+
+	return response, nil
 }
diff --git a/multi/blobsidecars.go b/multi/blobsidecars.go
index 941fe4fb..ddcdcb60 100644
--- a/multi/blobsidecars.go
+++ b/multi/blobsidecars.go
@@ -22,8 +22,12 @@ import (
 )
 
 // BlobSidecars fetches the blob sidecars given options.
-func (s *Service) BlobSidecars(ctx context.Context, opts *api.BlobSidecarsOpts) ([]*deneb.BlobSidecar, error) {
-	res, err := s.doCall(ctx, func(ctx context.Context, client consensusclient.Service) (interface{}, error) {
+func (s *Service) BlobSidecars(ctx context.Context,
+	opts *api.BlobSidecarsOpts,
+) (*api.Response[[]*deneb.BlobSidecar],
+	error,
+) {
+	res, err := s.doCall(ctx, func(ctx context.Context, client consensusclient.Service) (any, error) {
 		blobSidecars, err := client.(consensusclient.BlobSidecarsProvider).BlobSidecars(ctx, opts)
 		if err != nil {
 			return nil, err
@@ -34,9 +38,11 @@ func (s *Service) BlobSidecars(ctx context.Context, opts *api.BlobSidecarsOpts)
 	if err != nil {
 		return nil, err
 	}
-	if res == nil {
-		return nil, nil
+
+	response, isResponse := res.(*api.Response[[]*deneb.BlobSidecar])
+	if !isResponse {
+		return nil, ErrIncorrectType
 	}
 
-	return res.([]*deneb.BlobSidecar), nil
+	return response, nil
 }
diff --git a/multi/client.go b/multi/client.go
index 86c3a135..ecc748a6 100644
--- a/multi/client.go
+++ b/multi/client.go
@@ -129,7 +129,7 @@ func (s *Service) activateClient(ctx context.Context, client consensusclient.Ser
 
 // callFunc is the definition for a call function.  It provides a generic return interface
 // to allow the caller to unpick the results as it sees fit.
-type callFunc func(ctx context.Context, client consensusclient.Service) (interface{}, error)
+type callFunc func(ctx context.Context, client consensusclient.Service) (any, error)
 
 // errHandlerFunc is the definition for an error handler function.  It looks at the error
 // returned from the client, potentially rewrites it, and also states if the error should
@@ -137,7 +137,7 @@ type callFunc func(ctx context.Context, client consensusclient.Service) (interfa
 type errHandlerFunc func(ctx context.Context, client consensusclient.Service, err error) (bool, error)
 
 // doCall carries out a call on the active clients in turn until one succeeds.
-func (s *Service) doCall(ctx context.Context, call callFunc, errHandler errHandlerFunc) (interface{}, error) {
+func (s *Service) doCall(ctx context.Context, call callFunc, errHandler errHandlerFunc) (any, error) {
 	log := s.log.With().Logger()
 	ctx = log.WithContext(ctx)
 
@@ -159,7 +159,7 @@ func (s *Service) doCall(ctx context.Context, call callFunc, errHandler errHandl
 	}
 
 	var err error
-	var res interface{}
+	var res any
 	for _, client := range activeClients {
 		res, err = call(ctx, client)
 		if err != nil {
@@ -209,7 +209,7 @@ func (s *Service) doCall(ctx context.Context, call callFunc, errHandler errHandl
 
 // providerInfo returns information on the provider.
 // Currently this just returns the name of the service (lighthouse/teku/etc.).
-func (s *Service) providerInfo(ctx context.Context, provider consensusclient.Service) string {
+func (*Service) providerInfo(ctx context.Context, provider consensusclient.Service) string {
 	providerName := "<unknown>"
 	nodeVersionProvider, isNodeVersionProvider := provider.(consensusclient.NodeVersionProvider)
 	if isNodeVersionProvider {
diff --git a/multi/client_internal_test.go b/multi/client_internal_test.go
index dbef8e1c..7c2095bc 100644
--- a/multi/client_internal_test.go
+++ b/multi/client_internal_test.go
@@ -53,7 +53,7 @@ func TestDeactivateMulti(t *testing.T) {
 	multi := s.(*Service)
 
 	var wg sync.WaitGroup
-	starter := make(chan interface{})
+	starter := make(chan any)
 	for i := 0; i < 256; i++ {
 		wg.Add(1)
 		go func() {
@@ -100,7 +100,7 @@ func TestActivateMulti(t *testing.T) {
 	multi.deactivateClient(ctx, erroringClient2)
 
 	var wg sync.WaitGroup
-	starter := make(chan interface{})
+	starter := make(chan any)
 	for i := 0; i < 256; i++ {
 		wg.Add(1)
 		go func() {
diff --git a/multi/depositcontract.go b/multi/depositcontract.go
index 98999a0e..06210e3d 100644
--- a/multi/depositcontract.go
+++ b/multi/depositcontract.go
@@ -28,7 +28,7 @@ func (s *Service) DepositContract(ctx context.Context,
 	*api.Response[*apiv1.DepositContract],
 	error,
 ) {
-	res, err := s.doCall(ctx, func(ctx context.Context, client consensusclient.Service) (interface{}, error) {
+	res, err := s.doCall(ctx, func(ctx context.Context, client consensusclient.Service) (any, error) {
 		aggregate, err := client.(consensusclient.DepositContractProvider).DepositContract(ctx, opts)
 		if err != nil {
 			return nil, err
@@ -40,5 +40,10 @@ func (s *Service) DepositContract(ctx context.Context,
 		return nil, err
 	}
 
-	return res.(*api.Response[*apiv1.DepositContract]), nil
+	response, isResponse := res.(*api.Response[*apiv1.DepositContract])
+	if !isResponse {
+		return nil, ErrIncorrectType
+	}
+
+	return response, nil
 }
diff --git a/multi/domain.go b/multi/domain.go
index 7aab8d85..69ec7c7c 100644
--- a/multi/domain.go
+++ b/multi/domain.go
@@ -33,7 +33,7 @@ func (s *Service) Domain(ctx context.Context,
 	phase0.Domain,
 	error,
 ) {
-	res, err := s.doCall(ctx, func(ctx context.Context, client consensusclient.Service) (interface{}, error) {
+	res, err := s.doCall(ctx, func(ctx context.Context, client consensusclient.Service) (any, error) {
 		domain, err := client.(consensusclient.DomainProvider).Domain(ctx, domainType, epoch)
 		if err != nil {
 			return nil, err
@@ -48,7 +48,12 @@ func (s *Service) Domain(ctx context.Context,
 		return phase0.Domain{}, err
 	}
 
-	return res.(phase0.Domain), nil
+	response, isResponse := res.(phase0.Domain)
+	if !isResponse {
+		return phase0.Domain{}, ErrIncorrectType
+	}
+
+	return response, nil
 }
 
 // GenesisDomain provides a domain for a given domain type.
@@ -58,7 +63,7 @@ func (s *Service) GenesisDomain(ctx context.Context,
 	phase0.Domain,
 	error,
 ) {
-	res, err := s.doCall(ctx, func(ctx context.Context, client consensusclient.Service) (interface{}, error) {
+	res, err := s.doCall(ctx, func(ctx context.Context, client consensusclient.Service) (any, error) {
 		domain, err := client.(consensusclient.DomainProvider).GenesisDomain(ctx, domainType)
 		if err != nil {
 			return nil, err
@@ -73,5 +78,10 @@ func (s *Service) GenesisDomain(ctx context.Context,
 		return phase0.Domain{}, err
 	}
 
-	return res.(phase0.Domain), nil
+	response, isResponse := res.(phase0.Domain)
+	if !isResponse {
+		return phase0.Domain{}, ErrIncorrectType
+	}
+
+	return response, nil
 }
diff --git a/multi/errors.go b/multi/errors.go
new file mode 100644
index 00000000..0324cafc
--- /dev/null
+++ b/multi/errors.go
@@ -0,0 +1,19 @@
+// Copyright © 2024 Attestant Limited.
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package multi
+
+import "errors"
+
+// ErrIncorrectType is returned when the multi client obtain a response type it is not expecting.
+var ErrIncorrectType = errors.New("incorrect response type")
diff --git a/multi/farfutureepoch.go b/multi/farfutureepoch.go
index 6ed1efc5..63d6cfe3 100644
--- a/multi/farfutureepoch.go
+++ b/multi/farfutureepoch.go
@@ -23,7 +23,7 @@ import (
 
 // FarFutureEpoch provides the far future epoch of the chain.
 func (s *Service) FarFutureEpoch(ctx context.Context) (phase0.Epoch, error) {
-	res, err := s.doCall(ctx, func(ctx context.Context, client consensusclient.Service) (interface{}, error) {
+	res, err := s.doCall(ctx, func(ctx context.Context, client consensusclient.Service) (any, error) {
 		epoch, err := client.(consensusclient.FarFutureEpochProvider).FarFutureEpoch(ctx)
 		if err != nil {
 			return nil, err
@@ -38,5 +38,10 @@ func (s *Service) FarFutureEpoch(ctx context.Context) (phase0.Epoch, error) {
 		return 0, err
 	}
 
-	return res.(phase0.Epoch), nil
+	response, isResponse := res.(phase0.Epoch)
+	if !isResponse {
+		return 0, ErrIncorrectType
+	}
+
+	return response, nil
 }
diff --git a/multi/finality.go b/multi/finality.go
index 54bb0eb8..94ad4dc1 100644
--- a/multi/finality.go
+++ b/multi/finality.go
@@ -23,7 +23,7 @@ import (
 
 // Finality provides the finality given a state ID.
 func (s *Service) Finality(ctx context.Context, opts *api.FinalityOpts) (*api.Response[*apiv1.Finality], error) {
-	res, err := s.doCall(ctx, func(ctx context.Context, client consensusclient.Service) (interface{}, error) {
+	res, err := s.doCall(ctx, func(ctx context.Context, client consensusclient.Service) (any, error) {
 		finality, err := client.(consensusclient.FinalityProvider).Finality(ctx, opts)
 		if err != nil {
 			return nil, err
@@ -35,5 +35,10 @@ func (s *Service) Finality(ctx context.Context, opts *api.FinalityOpts) (*api.Re
 		return nil, err
 	}
 
-	return res.(*api.Response[*apiv1.Finality]), nil
+	response, isResponse := res.(*api.Response[*apiv1.Finality])
+	if !isResponse {
+		return nil, ErrIncorrectType
+	}
+
+	return response, nil
 }
diff --git a/multi/fork.go b/multi/fork.go
index 060377a3..8500b111 100644
--- a/multi/fork.go
+++ b/multi/fork.go
@@ -28,7 +28,7 @@ func (s *Service) Fork(ctx context.Context,
 	*api.Response[*phase0.Fork],
 	error,
 ) {
-	res, err := s.doCall(ctx, func(ctx context.Context, client consensusclient.Service) (interface{}, error) {
+	res, err := s.doCall(ctx, func(ctx context.Context, client consensusclient.Service) (any, error) {
 		fork, err := client.(consensusclient.ForkProvider).Fork(ctx, opts)
 		if err != nil {
 			return nil, err
@@ -40,5 +40,10 @@ func (s *Service) Fork(ctx context.Context,
 		return nil, err
 	}
 
-	return res.(*api.Response[*phase0.Fork]), nil
+	response, isResponse := res.(*api.Response[*phase0.Fork])
+	if !isResponse {
+		return nil, ErrIncorrectType
+	}
+
+	return response, nil
 }
diff --git a/multi/forkchoice.go b/multi/forkchoice.go
new file mode 100644
index 00000000..c34c8036
--- /dev/null
+++ b/multi/forkchoice.go
@@ -0,0 +1,49 @@
+// Copyright © 2024 Attestant Limited.
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package multi
+
+import (
+	"context"
+
+	consensusclient "github.com/attestantio/go-eth2-client"
+	"github.com/attestantio/go-eth2-client/api"
+	apiv1 "github.com/attestantio/go-eth2-client/api/v1"
+)
+
+// ForkChoice fetches all current fork choice context.
+func (s *Service) ForkChoice(ctx context.Context,
+	opts *api.ForkChoiceOpts,
+) (
+	*api.Response[*apiv1.ForkChoice],
+	error,
+) {
+	res, err := s.doCall(ctx, func(ctx context.Context, client consensusclient.Service) (any, error) {
+		aggregate, err := client.(consensusclient.ForkChoiceProvider).ForkChoice(ctx, opts)
+		if err != nil {
+			return nil, err
+		}
+
+		return aggregate, nil
+	}, nil)
+	if err != nil {
+		return nil, err
+	}
+
+	response, isResponse := res.(*api.Response[*apiv1.ForkChoice])
+	if !isResponse {
+		return nil, ErrIncorrectType
+	}
+
+	return response, nil
+}
diff --git a/multi/forkschedule.go b/multi/forkschedule.go
index 08b910bc..1b645f61 100644
--- a/multi/forkschedule.go
+++ b/multi/forkschedule.go
@@ -28,7 +28,7 @@ func (s *Service) ForkSchedule(ctx context.Context,
 	*api.Response[[]*phase0.Fork],
 	error,
 ) {
-	res, err := s.doCall(ctx, func(ctx context.Context, client consensusclient.Service) (interface{}, error) {
+	res, err := s.doCall(ctx, func(ctx context.Context, client consensusclient.Service) (any, error) {
 		forkSchedule, err := client.(consensusclient.ForkScheduleProvider).ForkSchedule(ctx, opts)
 		if err != nil {
 			return nil, err
@@ -40,5 +40,10 @@ func (s *Service) ForkSchedule(ctx context.Context,
 		return nil, err
 	}
 
-	return res.(*api.Response[[]*phase0.Fork]), nil
+	response, isResponse := res.(*api.Response[[]*phase0.Fork])
+	if !isResponse {
+		return nil, ErrIncorrectType
+	}
+
+	return response, nil
 }
diff --git a/multi/genesis.go b/multi/genesis.go
index d6cf002e..cb067469 100644
--- a/multi/genesis.go
+++ b/multi/genesis.go
@@ -28,7 +28,7 @@ func (s *Service) Genesis(ctx context.Context,
 	*api.Response[*apiv1.Genesis],
 	error,
 ) {
-	res, err := s.doCall(ctx, func(ctx context.Context, client consensusclient.Service) (interface{}, error) {
+	res, err := s.doCall(ctx, func(ctx context.Context, client consensusclient.Service) (any, error) {
 		genesis, err := client.(consensusclient.GenesisProvider).Genesis(ctx, opts)
 		if err != nil {
 			return nil, err
@@ -40,5 +40,10 @@ func (s *Service) Genesis(ctx context.Context,
 		return nil, err
 	}
 
-	return res.(*api.Response[*apiv1.Genesis]), nil
+	response, isResponse := res.(*api.Response[*apiv1.Genesis])
+	if !isResponse {
+		return nil, ErrIncorrectType
+	}
+
+	return response, nil
 }
diff --git a/multi/genesistime.go b/multi/genesistime.go
index 6a8c7a30..0e7b8ac5 100644
--- a/multi/genesistime.go
+++ b/multi/genesistime.go
@@ -25,7 +25,7 @@ import (
 //
 // Deprecated: use Genesis().
 func (s *Service) GenesisTime(ctx context.Context) (time.Time, error) {
-	res, err := s.doCall(ctx, func(ctx context.Context, client consensusclient.Service) (interface{}, error) {
+	res, err := s.doCall(ctx, func(ctx context.Context, client consensusclient.Service) (any, error) {
 		genesisTime, err := client.(consensusclient.GenesisTimeProvider).GenesisTime(ctx)
 		if err != nil {
 			return nil, err
@@ -40,5 +40,10 @@ func (s *Service) GenesisTime(ctx context.Context) (time.Time, error) {
 		return time.Time{}, err
 	}
 
-	return res.(time.Time), nil
+	response, isResponse := res.(time.Time)
+	if !isResponse {
+		return time.Time{}, ErrIncorrectType
+	}
+
+	return response, nil
 }
diff --git a/multi/nodepeers.go b/multi/nodepeers.go
index 085f22d0..5dd7316d 100644
--- a/multi/nodepeers.go
+++ b/multi/nodepeers.go
@@ -23,7 +23,7 @@ import (
 
 // NodePeers provides the peers of the node.
 func (s *Service) NodePeers(ctx context.Context, opts *api.NodePeersOpts) (*api.Response[[]*apiv1.Peer], error) {
-	res, err := s.doCall(ctx, func(ctx context.Context, client consensusclient.Service) (interface{}, error) {
+	res, err := s.doCall(ctx, func(ctx context.Context, client consensusclient.Service) (any, error) {
 		nodePeers, err := client.(consensusclient.NodePeersProvider).NodePeers(ctx, opts)
 		if err != nil {
 			return nil, err
@@ -35,5 +35,10 @@ func (s *Service) NodePeers(ctx context.Context, opts *api.NodePeersOpts) (*api.
 		return nil, err
 	}
 
-	return res.(*api.Response[[]*apiv1.Peer]), nil
+	response, isResponse := res.(*api.Response[[]*apiv1.Peer])
+	if !isResponse {
+		return nil, ErrIncorrectType
+	}
+
+	return response, nil
 }
diff --git a/multi/nodesyncing.go b/multi/nodesyncing.go
index 760827b2..118d21b3 100644
--- a/multi/nodesyncing.go
+++ b/multi/nodesyncing.go
@@ -28,7 +28,7 @@ func (s *Service) NodeSyncing(ctx context.Context,
 	*api.Response[*apiv1.SyncState],
 	error,
 ) {
-	res, err := s.doCall(ctx, func(ctx context.Context, client consensusclient.Service) (interface{}, error) {
+	res, err := s.doCall(ctx, func(ctx context.Context, client consensusclient.Service) (any, error) {
 		nodeSyncing, err := client.(consensusclient.NodeSyncingProvider).NodeSyncing(ctx, opts)
 		if err != nil {
 			return nil, err
@@ -40,5 +40,10 @@ func (s *Service) NodeSyncing(ctx context.Context,
 		return nil, err
 	}
 
-	return res.(*api.Response[*apiv1.SyncState]), nil
+	response, isResponse := res.(*api.Response[*apiv1.SyncState])
+	if !isResponse {
+		return nil, ErrIncorrectType
+	}
+
+	return response, nil
 }
diff --git a/multi/nodeversion.go b/multi/nodeversion.go
index a5d21ef0..eb4008e0 100644
--- a/multi/nodeversion.go
+++ b/multi/nodeversion.go
@@ -22,7 +22,7 @@ import (
 
 // NodeVersion provides the version information of the node.
 func (s *Service) NodeVersion(ctx context.Context, opts *api.NodeVersionOpts) (*api.Response[string], error) {
-	res, err := s.doCall(ctx, func(ctx context.Context, client consensusclient.Service) (interface{}, error) {
+	res, err := s.doCall(ctx, func(ctx context.Context, client consensusclient.Service) (any, error) {
 		aggregate, err := client.(consensusclient.NodeVersionProvider).NodeVersion(ctx, opts)
 		if err != nil {
 			return nil, err
@@ -34,5 +34,10 @@ func (s *Service) NodeVersion(ctx context.Context, opts *api.NodeVersionOpts) (*
 		return nil, err
 	}
 
-	return res.(*api.Response[string]), nil
+	response, isResponse := res.(*api.Response[string])
+	if !isResponse {
+		return nil, ErrIncorrectType
+	}
+
+	return response, nil
 }
diff --git a/multi/proposal.go b/multi/proposal.go
index 5290e234..59d4ec34 100644
--- a/multi/proposal.go
+++ b/multi/proposal.go
@@ -27,7 +27,7 @@ func (s *Service) Proposal(ctx context.Context,
 	*api.Response[*api.VersionedProposal],
 	error,
 ) {
-	res, err := s.doCall(ctx, func(ctx context.Context, client consensusclient.Service) (interface{}, error) {
+	res, err := s.doCall(ctx, func(ctx context.Context, client consensusclient.Service) (any, error) {
 		block, err := client.(consensusclient.ProposalProvider).Proposal(ctx, opts)
 		if err != nil {
 			return nil, err
@@ -39,5 +39,10 @@ func (s *Service) Proposal(ctx context.Context,
 		return nil, err
 	}
 
-	return res.(*api.Response[*api.VersionedProposal]), nil
+	response, isResponse := res.(*api.Response[*api.VersionedProposal])
+	if !isResponse {
+		return nil, ErrIncorrectType
+	}
+
+	return response, nil
 }
diff --git a/multi/proposerduties.go b/multi/proposerduties.go
index afcafc43..c5e592ca 100644
--- a/multi/proposerduties.go
+++ b/multi/proposerduties.go
@@ -29,7 +29,7 @@ func (s *Service) ProposerDuties(ctx context.Context,
 	*api.Response[[]*apiv1.ProposerDuty],
 	error,
 ) {
-	res, err := s.doCall(ctx, func(ctx context.Context, client consensusclient.Service) (interface{}, error) {
+	res, err := s.doCall(ctx, func(ctx context.Context, client consensusclient.Service) (any, error) {
 		block, err := client.(consensusclient.ProposerDutiesProvider).ProposerDuties(ctx, opts)
 		if err != nil {
 			return nil, err
@@ -41,5 +41,10 @@ func (s *Service) ProposerDuties(ctx context.Context,
 		return nil, err
 	}
 
-	return res.(*api.Response[[]*apiv1.ProposerDuty]), nil
+	response, isResponse := res.(*api.Response[[]*apiv1.ProposerDuty])
+	if !isResponse {
+		return nil, ErrIncorrectType
+	}
+
+	return response, nil
 }
diff --git a/multi/service.go b/multi/service.go
index 5e9460ef..e28d0ac6 100644
--- a/multi/service.go
+++ b/multi/service.go
@@ -118,7 +118,7 @@ func New(ctx context.Context, params ...Parameter) (consensusclient.Service, err
 }
 
 // Name returns the name of the client implementation.
-func (s *Service) Name() string {
+func (*Service) Name() string {
 	return "multi"
 }
 
diff --git a/multi/service_test.go b/multi/service_test.go
index 8f6ee560..e5cfd1d3 100644
--- a/multi/service_test.go
+++ b/multi/service_test.go
@@ -113,10 +113,12 @@ func TestInterfaces(t *testing.T) {
 	assert.Implements(t, (*client.BeaconCommitteeSubscriptionsSubmitter)(nil), s)
 	assert.Implements(t, (*client.BeaconStateProvider)(nil), s)
 	assert.Implements(t, (*client.BlindedBeaconBlockSubmitter)(nil), s)
+	assert.Implements(t, (*client.BlobSidecarsProvider)(nil), s)
 	assert.Implements(t, (*client.ValidatorRegistrationsSubmitter)(nil), s)
 	assert.Implements(t, (*client.DepositContractProvider)(nil), s)
 	assert.Implements(t, (*client.EventsProvider)(nil), s)
 	assert.Implements(t, (*client.FinalityProvider)(nil), s)
+	assert.Implements(t, (*client.ForkChoiceProvider)(nil), s)
 	assert.Implements(t, (*client.ForkProvider)(nil), s)
 	assert.Implements(t, (*client.ForkScheduleProvider)(nil), s)
 	assert.Implements(t, (*client.GenesisProvider)(nil), s)
diff --git a/multi/signedbeaconblock.go b/multi/signedbeaconblock.go
index fd1a0b9e..171df398 100644
--- a/multi/signedbeaconblock.go
+++ b/multi/signedbeaconblock.go
@@ -28,7 +28,7 @@ func (s *Service) SignedBeaconBlock(ctx context.Context,
 	*api.Response[*spec.VersionedSignedBeaconBlock],
 	error,
 ) {
-	res, err := s.doCall(ctx, func(ctx context.Context, client consensusclient.Service) (interface{}, error) {
+	res, err := s.doCall(ctx, func(ctx context.Context, client consensusclient.Service) (any, error) {
 		block, err := client.(consensusclient.SignedBeaconBlockProvider).SignedBeaconBlock(ctx, opts)
 		if err != nil {
 			return nil, err
@@ -40,5 +40,10 @@ func (s *Service) SignedBeaconBlock(ctx context.Context,
 		return nil, err
 	}
 
-	return res.(*api.Response[*spec.VersionedSignedBeaconBlock]), nil
+	response, isResponse := res.(*api.Response[*spec.VersionedSignedBeaconBlock])
+	if !isResponse {
+		return nil, ErrIncorrectType
+	}
+
+	return response, nil
 }
diff --git a/multi/slotduration.go b/multi/slotduration.go
index a559849c..ae5754da 100644
--- a/multi/slotduration.go
+++ b/multi/slotduration.go
@@ -25,7 +25,7 @@ import (
 //
 // Deprecated: use Spec().
 func (s *Service) SlotDuration(ctx context.Context) (time.Duration, error) {
-	res, err := s.doCall(ctx, func(ctx context.Context, client consensusclient.Service) (interface{}, error) {
+	res, err := s.doCall(ctx, func(ctx context.Context, client consensusclient.Service) (any, error) {
 		duration, err := client.(consensusclient.SlotDurationProvider).SlotDuration(ctx)
 		if err != nil {
 			return nil, err
@@ -40,5 +40,10 @@ func (s *Service) SlotDuration(ctx context.Context) (time.Duration, error) {
 		return 0, err
 	}
 
-	return res.(time.Duration), nil
+	response, isResponse := res.(time.Duration)
+	if !isResponse {
+		return 0, ErrIncorrectType
+	}
+
+	return response, nil
 }
diff --git a/multi/slotsperepoch.go b/multi/slotsperepoch.go
index b56f3cc1..b16f831c 100644
--- a/multi/slotsperepoch.go
+++ b/multi/slotsperepoch.go
@@ -24,7 +24,7 @@ import (
 //
 // Deprecated: use Spec().
 func (s *Service) SlotsPerEpoch(ctx context.Context) (uint64, error) {
-	res, err := s.doCall(ctx, func(ctx context.Context, client consensusclient.Service) (interface{}, error) {
+	res, err := s.doCall(ctx, func(ctx context.Context, client consensusclient.Service) (any, error) {
 		slotsPerEpoch, err := client.(consensusclient.SlotsPerEpochProvider).SlotsPerEpoch(ctx)
 		if err != nil {
 			return nil, err
@@ -39,5 +39,10 @@ func (s *Service) SlotsPerEpoch(ctx context.Context) (uint64, error) {
 		return 0, err
 	}
 
-	return res.(uint64), nil
+	response, isResponse := res.(uint64)
+	if !isResponse {
+		return 0, ErrIncorrectType
+	}
+
+	return response, nil
 }
diff --git a/multi/spec.go b/multi/spec.go
index 2557d248..e7404dc7 100644
--- a/multi/spec.go
+++ b/multi/spec.go
@@ -27,7 +27,7 @@ func (s *Service) Spec(ctx context.Context,
 	*api.Response[map[string]any],
 	error,
 ) {
-	res, err := s.doCall(ctx, func(ctx context.Context, client consensusclient.Service) (interface{}, error) {
+	res, err := s.doCall(ctx, func(ctx context.Context, client consensusclient.Service) (any, error) {
 		aggregate, err := client.(consensusclient.SpecProvider).Spec(ctx, opts)
 		if err != nil {
 			return nil, err
@@ -39,5 +39,10 @@ func (s *Service) Spec(ctx context.Context,
 		return nil, err
 	}
 
-	return res.(*api.Response[map[string]any]), nil
+	response, isResponse := res.(*api.Response[map[string]any])
+	if !isResponse {
+		return nil, ErrIncorrectType
+	}
+
+	return response, nil
 }
diff --git a/multi/stateroot.go b/multi/stateroot.go
index 2fa62f52..dd1c59ed 100644
--- a/multi/stateroot.go
+++ b/multi/stateroot.go
@@ -28,7 +28,7 @@ func (s *Service) BeaconStateRoot(ctx context.Context,
 	*api.Response[*phase0.Root],
 	error,
 ) {
-	res, err := s.doCall(ctx, func(ctx context.Context, client consensusclient.Service) (interface{}, error) {
+	res, err := s.doCall(ctx, func(ctx context.Context, client consensusclient.Service) (any, error) {
 		stateRoot, err := client.(consensusclient.BeaconStateRootProvider).BeaconStateRoot(ctx, opts)
 		if err != nil {
 			return nil, err
@@ -40,5 +40,10 @@ func (s *Service) BeaconStateRoot(ctx context.Context,
 		return nil, err
 	}
 
-	return res.(*api.Response[*phase0.Root]), nil
+	response, isResponse := res.(*api.Response[*phase0.Root])
+	if !isResponse {
+		return nil, ErrIncorrectType
+	}
+
+	return response, nil
 }
diff --git a/multi/submitaggregateattestations.go b/multi/submitaggregateattestations.go
index 1010a5f8..0329d201 100644
--- a/multi/submitaggregateattestations.go
+++ b/multi/submitaggregateattestations.go
@@ -24,7 +24,7 @@ import (
 func (s *Service) SubmitAggregateAttestations(ctx context.Context,
 	aggregateAndProofs []*phase0.SignedAggregateAndProof,
 ) error {
-	_, err := s.doCall(ctx, func(ctx context.Context, client consensusclient.Service) (interface{}, error) {
+	_, err := s.doCall(ctx, func(ctx context.Context, client consensusclient.Service) (any, error) {
 		err := client.(consensusclient.AggregateAttestationsSubmitter).SubmitAggregateAttestations(ctx, aggregateAndProofs)
 		if err != nil {
 			return nil, err
diff --git a/multi/submitattestations.go b/multi/submitattestations.go
index c0a3ec68..faa0baa5 100644
--- a/multi/submitattestations.go
+++ b/multi/submitattestations.go
@@ -25,7 +25,7 @@ import (
 func (s *Service) SubmitAttestations(ctx context.Context,
 	attestations []*phase0.Attestation,
 ) error {
-	_, err := s.doCall(ctx, func(ctx context.Context, client consensusclient.Service) (interface{}, error) {
+	_, err := s.doCall(ctx, func(ctx context.Context, client consensusclient.Service) (any, error) {
 		err := client.(consensusclient.AttestationsSubmitter).SubmitAttestations(ctx, attestations)
 		if err != nil {
 			return nil, err
diff --git a/multi/submitbeaconblock.go b/multi/submitbeaconblock.go
index b7c3455c..81283ac8 100644
--- a/multi/submitbeaconblock.go
+++ b/multi/submitbeaconblock.go
@@ -24,7 +24,7 @@ import (
 //
 // Deprecated: this will not work from the deneb hard-fork onwards.  Use SubmitProposal() instead.
 func (s *Service) SubmitBeaconBlock(ctx context.Context, block *spec.VersionedSignedBeaconBlock) error {
-	_, err := s.doCall(ctx, func(ctx context.Context, client consensusclient.Service) (interface{}, error) {
+	_, err := s.doCall(ctx, func(ctx context.Context, client consensusclient.Service) (any, error) {
 		err := client.(consensusclient.BeaconBlockSubmitter).SubmitBeaconBlock(ctx, block)
 		if err != nil {
 			return nil, err
diff --git a/multi/submitbeaconcommitteesubscriptions.go b/multi/submitbeaconcommitteesubscriptions.go
index 324b182d..96fe1d59 100644
--- a/multi/submitbeaconcommitteesubscriptions.go
+++ b/multi/submitbeaconcommitteesubscriptions.go
@@ -24,7 +24,7 @@ import (
 func (s *Service) SubmitBeaconCommitteeSubscriptions(ctx context.Context,
 	subscriptions []*api.BeaconCommitteeSubscription,
 ) error {
-	_, err := s.doCall(ctx, func(ctx context.Context, client consensusclient.Service) (interface{}, error) {
+	_, err := s.doCall(ctx, func(ctx context.Context, client consensusclient.Service) (any, error) {
 		err := client.(consensusclient.BeaconCommitteeSubscriptionsSubmitter).SubmitBeaconCommitteeSubscriptions(ctx, subscriptions)
 		if err != nil {
 			return nil, err
diff --git a/multi/submitblindedbeaconblock.go b/multi/submitblindedbeaconblock.go
index 9b1a71c0..a4c10672 100644
--- a/multi/submitblindedbeaconblock.go
+++ b/multi/submitblindedbeaconblock.go
@@ -24,7 +24,7 @@ import (
 //
 // Deprecated: this will not work from the deneb hard-fork onwards.  Use SubmitBlindedProposal() instead.
 func (s *Service) SubmitBlindedBeaconBlock(ctx context.Context, block *api.VersionedSignedBlindedBeaconBlock) error {
-	_, err := s.doCall(ctx, func(ctx context.Context, client consensusclient.Service) (interface{}, error) {
+	_, err := s.doCall(ctx, func(ctx context.Context, client consensusclient.Service) (any, error) {
 		err := client.(consensusclient.BlindedBeaconBlockSubmitter).SubmitBlindedBeaconBlock(ctx, block)
 		if err != nil {
 			return nil, err
diff --git a/multi/submitproposal.go b/multi/submitproposal.go
index df058c66..6d6d9831 100644
--- a/multi/submitproposal.go
+++ b/multi/submitproposal.go
@@ -24,7 +24,7 @@ import (
 func (s *Service) SubmitProposal(ctx context.Context,
 	opts *api.SubmitProposalOpts,
 ) error {
-	_, err := s.doCall(ctx, func(ctx context.Context, client consensusclient.Service) (interface{}, error) {
+	_, err := s.doCall(ctx, func(ctx context.Context, client consensusclient.Service) (any, error) {
 		err := client.(consensusclient.ProposalSubmitter).SubmitProposal(ctx, opts)
 		if err != nil {
 			return nil, err
diff --git a/multi/submitproposalpreparations.go b/multi/submitproposalpreparations.go
index 9f9cd55b..87d25e46 100644
--- a/multi/submitproposalpreparations.go
+++ b/multi/submitproposalpreparations.go
@@ -25,7 +25,7 @@ import (
 func (s *Service) SubmitProposalPreparations(ctx context.Context,
 	preparations []*apiv1.ProposalPreparation,
 ) error {
-	_, err := s.doCall(ctx, func(ctx context.Context, client consensusclient.Service) (interface{}, error) {
+	_, err := s.doCall(ctx, func(ctx context.Context, client consensusclient.Service) (any, error) {
 		err := client.(consensusclient.ProposalPreparationsSubmitter).SubmitProposalPreparations(ctx, preparations)
 		if err != nil {
 			return nil, err
diff --git a/multi/submitsynccommitteecontributions.go b/multi/submitsynccommitteecontributions.go
index f2af9117..bc59d2dc 100644
--- a/multi/submitsynccommitteecontributions.go
+++ b/multi/submitsynccommitteecontributions.go
@@ -24,7 +24,7 @@ import (
 func (s *Service) SubmitSyncCommitteeContributions(ctx context.Context,
 	contributionAndProofs []*altair.SignedContributionAndProof,
 ) error {
-	_, err := s.doCall(ctx, func(ctx context.Context, client consensusclient.Service) (interface{}, error) {
+	_, err := s.doCall(ctx, func(ctx context.Context, client consensusclient.Service) (any, error) {
 		err := client.(consensusclient.SyncCommitteeContributionsSubmitter).SubmitSyncCommitteeContributions(ctx, contributionAndProofs)
 		if err != nil {
 			return nil, err
diff --git a/multi/submitsynccommitteemessages.go b/multi/submitsynccommitteemessages.go
index 2948ab63..4153ee48 100644
--- a/multi/submitsynccommitteemessages.go
+++ b/multi/submitsynccommitteemessages.go
@@ -24,7 +24,7 @@ import (
 func (s *Service) SubmitSyncCommitteeMessages(ctx context.Context,
 	messages []*altair.SyncCommitteeMessage,
 ) error {
-	_, err := s.doCall(ctx, func(ctx context.Context, client consensusclient.Service) (interface{}, error) {
+	_, err := s.doCall(ctx, func(ctx context.Context, client consensusclient.Service) (any, error) {
 		err := client.(consensusclient.SyncCommitteeMessagesSubmitter).SubmitSyncCommitteeMessages(ctx, messages)
 		if err != nil {
 			return nil, err
diff --git a/multi/submitsynccommitteesubscriptions.go b/multi/submitsynccommitteesubscriptions.go
index c23c119b..e33e4be1 100644
--- a/multi/submitsynccommitteesubscriptions.go
+++ b/multi/submitsynccommitteesubscriptions.go
@@ -24,7 +24,7 @@ import (
 func (s *Service) SubmitSyncCommitteeSubscriptions(ctx context.Context,
 	subscriptions []*api.SyncCommitteeSubscription,
 ) error {
-	_, err := s.doCall(ctx, func(ctx context.Context, client consensusclient.Service) (interface{}, error) {
+	_, err := s.doCall(ctx, func(ctx context.Context, client consensusclient.Service) (any, error) {
 		err := client.(consensusclient.SyncCommitteeSubscriptionsSubmitter).SubmitSyncCommitteeSubscriptions(ctx, subscriptions)
 		if err != nil {
 			return nil, err
diff --git a/multi/submitvalidatorregistrations.go b/multi/submitvalidatorregistrations.go
index bed43ad2..26d64390 100644
--- a/multi/submitvalidatorregistrations.go
+++ b/multi/submitvalidatorregistrations.go
@@ -22,7 +22,7 @@ import (
 
 // SubmitValidatorRegistrations submits a validator registration.
 func (s *Service) SubmitValidatorRegistrations(ctx context.Context, registrations []*api.VersionedSignedValidatorRegistration) error {
-	_, err := s.doCall(ctx, func(ctx context.Context, client consensusclient.Service) (interface{}, error) {
+	_, err := s.doCall(ctx, func(ctx context.Context, client consensusclient.Service) (any, error) {
 		err := client.(consensusclient.ValidatorRegistrationsSubmitter).SubmitValidatorRegistrations(ctx, registrations)
 		if err != nil {
 			return nil, err
diff --git a/multi/submitvoluntaryexit.go b/multi/submitvoluntaryexit.go
index 0f1c72b5..d6ebc24f 100644
--- a/multi/submitvoluntaryexit.go
+++ b/multi/submitvoluntaryexit.go
@@ -22,7 +22,7 @@ import (
 
 // SubmitVoluntaryExit submits a voluntary exit.
 func (s *Service) SubmitVoluntaryExit(ctx context.Context, voluntaryExit *phase0.SignedVoluntaryExit) error {
-	_, err := s.doCall(ctx, func(ctx context.Context, client consensusclient.Service) (interface{}, error) {
+	_, err := s.doCall(ctx, func(ctx context.Context, client consensusclient.Service) (any, error) {
 		err := client.(consensusclient.VoluntaryExitSubmitter).SubmitVoluntaryExit(ctx, voluntaryExit)
 		if err != nil {
 			return nil, err
diff --git a/multi/synccommitteecontribution.go b/multi/synccommitteecontribution.go
index 4486bfb8..8e57cdd6 100644
--- a/multi/synccommitteecontribution.go
+++ b/multi/synccommitteecontribution.go
@@ -28,7 +28,7 @@ func (s *Service) SyncCommitteeContribution(ctx context.Context,
 	*api.Response[*altair.SyncCommitteeContribution],
 	error,
 ) {
-	res, err := s.doCall(ctx, func(ctx context.Context, client consensusclient.Service) (interface{}, error) {
+	res, err := s.doCall(ctx, func(ctx context.Context, client consensusclient.Service) (any, error) {
 		block, err := client.(consensusclient.SyncCommitteeContributionProvider).SyncCommitteeContribution(ctx, opts)
 		if err != nil {
 			return nil, err
@@ -40,5 +40,10 @@ func (s *Service) SyncCommitteeContribution(ctx context.Context,
 		return nil, err
 	}
 
-	return res.(*api.Response[*altair.SyncCommitteeContribution]), nil
+	response, isResponse := res.(*api.Response[*altair.SyncCommitteeContribution])
+	if !isResponse {
+		return nil, ErrIncorrectType
+	}
+
+	return response, nil
 }
diff --git a/multi/synccommitteeduties.go b/multi/synccommitteeduties.go
index 3324fdfc..5723323a 100644
--- a/multi/synccommitteeduties.go
+++ b/multi/synccommitteeduties.go
@@ -29,7 +29,7 @@ func (s *Service) SyncCommitteeDuties(ctx context.Context,
 	*api.Response[[]*apiv1.SyncCommitteeDuty],
 	error,
 ) {
-	res, err := s.doCall(ctx, func(ctx context.Context, client consensusclient.Service) (interface{}, error) {
+	res, err := s.doCall(ctx, func(ctx context.Context, client consensusclient.Service) (any, error) {
 		response, err := client.(consensusclient.SyncCommitteeDutiesProvider).SyncCommitteeDuties(ctx, opts)
 		if err != nil {
 			return nil, err
@@ -41,5 +41,10 @@ func (s *Service) SyncCommitteeDuties(ctx context.Context,
 		return nil, err
 	}
 
-	return res.(*api.Response[[]*apiv1.SyncCommitteeDuty]), nil
+	response, isResponse := res.(*api.Response[[]*apiv1.SyncCommitteeDuty])
+	if !isResponse {
+		return nil, ErrIncorrectType
+	}
+
+	return response, nil
 }
diff --git a/multi/synccommittees.go b/multi/synccommittees.go
index 36b4ca5a..94626dd4 100644
--- a/multi/synccommittees.go
+++ b/multi/synccommittees.go
@@ -23,7 +23,7 @@ import (
 
 // SyncCommittee fetches the sync committee for the given state.
 func (s *Service) SyncCommittee(ctx context.Context, opts *api.SyncCommitteeOpts) (*api.Response[*apiv1.SyncCommittee], error) {
-	res, err := s.doCall(ctx, func(ctx context.Context, client consensusclient.Service) (interface{}, error) {
+	res, err := s.doCall(ctx, func(ctx context.Context, client consensusclient.Service) (any, error) {
 		block, err := client.(consensusclient.SyncCommitteesProvider).SyncCommittee(ctx, opts)
 		if err != nil {
 			return nil, err
@@ -35,5 +35,10 @@ func (s *Service) SyncCommittee(ctx context.Context, opts *api.SyncCommitteeOpts
 		return nil, err
 	}
 
-	return res.(*api.Response[*apiv1.SyncCommittee]), nil
+	response, isResponse := res.(*api.Response[*apiv1.SyncCommittee])
+	if !isResponse {
+		return nil, ErrIncorrectType
+	}
+
+	return response, nil
 }
diff --git a/multi/targetaggregatorspercommittee.go b/multi/targetaggregatorspercommittee.go
index 8e234f55..ca91ae75 100644
--- a/multi/targetaggregatorspercommittee.go
+++ b/multi/targetaggregatorspercommittee.go
@@ -24,7 +24,7 @@ import (
 //
 // Deprecated:  Use Spec().
 func (s *Service) TargetAggregatorsPerCommittee(ctx context.Context) (uint64, error) {
-	res, err := s.doCall(ctx, func(ctx context.Context, client consensusclient.Service) (interface{}, error) {
+	res, err := s.doCall(ctx, func(ctx context.Context, client consensusclient.Service) (any, error) {
 		aggregators, err := client.(consensusclient.TargetAggregatorsPerCommitteeProvider).TargetAggregatorsPerCommittee(ctx)
 		if err != nil {
 			return nil, err
@@ -39,5 +39,10 @@ func (s *Service) TargetAggregatorsPerCommittee(ctx context.Context) (uint64, er
 		return 0, err
 	}
 
-	return res.(uint64), nil
+	response, isResponse := res.(uint64)
+	if !isResponse {
+		return 0, ErrIncorrectType
+	}
+
+	return response, nil
 }
diff --git a/multi/validatorbalances.go b/multi/validatorbalances.go
index 90f6503b..949177b2 100644
--- a/multi/validatorbalances.go
+++ b/multi/validatorbalances.go
@@ -28,7 +28,7 @@ func (s *Service) ValidatorBalances(ctx context.Context,
 	*api.Response[map[phase0.ValidatorIndex]phase0.Gwei],
 	error,
 ) {
-	res, err := s.doCall(ctx, func(ctx context.Context, client consensusclient.Service) (interface{}, error) {
+	res, err := s.doCall(ctx, func(ctx context.Context, client consensusclient.Service) (any, error) {
 		block, err := client.(consensusclient.ValidatorBalancesProvider).ValidatorBalances(ctx, opts)
 		if err != nil {
 			return nil, err
@@ -40,5 +40,10 @@ func (s *Service) ValidatorBalances(ctx context.Context,
 		return nil, err
 	}
 
-	return res.(*api.Response[map[phase0.ValidatorIndex]phase0.Gwei]), nil
+	response, isResponse := res.(*api.Response[map[phase0.ValidatorIndex]phase0.Gwei])
+	if !isResponse {
+		return nil, ErrIncorrectType
+	}
+
+	return response, nil
 }
diff --git a/multi/validators.go b/multi/validators.go
index 33cfeddd..121864eb 100644
--- a/multi/validators.go
+++ b/multi/validators.go
@@ -29,7 +29,7 @@ func (s *Service) Validators(ctx context.Context,
 	*api.Response[map[phase0.ValidatorIndex]*apiv1.Validator],
 	error,
 ) {
-	res, err := s.doCall(ctx, func(ctx context.Context, client consensusclient.Service) (interface{}, error) {
+	res, err := s.doCall(ctx, func(ctx context.Context, client consensusclient.Service) (any, error) {
 		block, err := client.(consensusclient.ValidatorsProvider).Validators(ctx, opts)
 		if err != nil {
 			return nil, err
@@ -41,5 +41,10 @@ func (s *Service) Validators(ctx context.Context,
 		return nil, err
 	}
 
-	return res.(*api.Response[map[phase0.ValidatorIndex]*apiv1.Validator]), nil
+	response, isResponse := res.(*api.Response[map[phase0.ValidatorIndex]*apiv1.Validator])
+	if !isResponse {
+		return nil, ErrIncorrectType
+	}
+
+	return response, nil
 }
diff --git a/multi/voluntaryexitpool.go b/multi/voluntaryexitpool.go
index 24b6b151..ced2675c 100644
--- a/multi/voluntaryexitpool.go
+++ b/multi/voluntaryexitpool.go
@@ -28,7 +28,7 @@ func (s *Service) VoluntaryExitPool(ctx context.Context,
 	*api.Response[[]*phase0.SignedVoluntaryExit],
 	error,
 ) {
-	res, err := s.doCall(ctx, func(ctx context.Context, client consensusclient.Service) (interface{}, error) {
+	res, err := s.doCall(ctx, func(ctx context.Context, client consensusclient.Service) (any, error) {
 		voluntaryExitPool, err := client.(consensusclient.VoluntaryExitPoolProvider).VoluntaryExitPool(ctx, opts)
 		if err != nil {
 			return nil, err
@@ -40,5 +40,10 @@ func (s *Service) VoluntaryExitPool(ctx context.Context,
 		return nil, err
 	}
 
-	return res.(*api.Response[[]*phase0.SignedVoluntaryExit]), nil
+	response, isResponse := res.(*api.Response[[]*phase0.SignedVoluntaryExit])
+	if !isResponse {
+		return nil, ErrIncorrectType
+	}
+
+	return response, nil
 }
diff --git a/service.go b/service.go
index 90544a71..adbeb1fa 100644
--- a/service.go
+++ b/service.go
@@ -17,7 +17,7 @@ import (
 	"context"
 	"time"
 
-	api "github.com/attestantio/go-eth2-client/api"
+	"github.com/attestantio/go-eth2-client/api"
 	apiv1 "github.com/attestantio/go-eth2-client/api/v1"
 	"github.com/attestantio/go-eth2-client/spec"
 	"github.com/attestantio/go-eth2-client/spec/altair"
diff --git a/spec/bellatrix/executionaddress.go b/spec/bellatrix/executionaddress.go
index cc012a62..feaa356d 100644
--- a/spec/bellatrix/executionaddress.go
+++ b/spec/bellatrix/executionaddress.go
@@ -34,25 +34,25 @@ func (a ExecutionAddress) IsZero() bool {
 
 // String returns an EIP-55 string version of the address.
 func (a ExecutionAddress) String() string {
-	bytes := []byte(hex.EncodeToString(a[:]))
+	data := []byte(hex.EncodeToString(a[:]))
 
 	keccak := sha3.NewLegacyKeccak256()
-	keccak.Write(bytes)
+	keccak.Write(data)
 	hash := keccak.Sum(nil)
 
-	for i := 0; i < len(bytes); i++ {
+	for i := 0; i < len(data); i++ {
 		hashByte := hash[i/2]
 		if i%2 == 0 {
 			hashByte >>= 4
 		} else {
 			hashByte &= 0xf
 		}
-		if bytes[i] > '9' && hashByte > 7 {
-			bytes[i] -= 32
+		if data[i] > '9' && hashByte > 7 {
+			data[i] -= 32
 		}
 	}
 
-	return fmt.Sprintf("0x%s", string(bytes))
+	return fmt.Sprintf("0x%s", string(data))
 }
 
 // Format formats the execution address.
diff --git a/spec/bellatrix/executionpayload.go b/spec/bellatrix/executionpayload.go
index 284a012c..07f25c73 100644
--- a/spec/bellatrix/executionpayload.go
+++ b/spec/bellatrix/executionpayload.go
@@ -243,7 +243,7 @@ func (e *ExecutionPayload) unpack(data *executionPayloadJSON) error {
 	}
 	switch {
 	case data.ExtraData == "0x", data.ExtraData == "0":
-		e.ExtraData = []byte{}
+		e.ExtraData = make([]byte, 0)
 	default:
 		data.ExtraData = strings.TrimPrefix(data.ExtraData, "0x")
 		if len(data.ExtraData)%2 == 1 {
diff --git a/spec/capella/executionpayload.go b/spec/capella/executionpayload.go
index 92faaed8..561d40c9 100644
--- a/spec/capella/executionpayload.go
+++ b/spec/capella/executionpayload.go
@@ -248,7 +248,7 @@ func (e *ExecutionPayload) unpack(data *executionPayloadJSON) error {
 	}
 	switch {
 	case data.ExtraData == "0x", data.ExtraData == "0":
-		e.ExtraData = []byte{}
+		e.ExtraData = make([]byte, 0)
 	default:
 		data.ExtraData = strings.TrimPrefix(data.ExtraData, "0x")
 		if len(data.ExtraData)%2 == 1 {
diff --git a/spec/deneb/beaconblock_yaml.go b/spec/deneb/beaconblock_yaml.go
index 5e9736f4..9ebe4168 100644
--- a/spec/deneb/beaconblock_yaml.go
+++ b/spec/deneb/beaconblock_yaml.go
@@ -50,14 +50,14 @@ func (b *BeaconBlock) MarshalYAML() ([]byte, error) {
 func (b *BeaconBlock) UnmarshalYAML(input []byte) error {
 	// This is very inefficient, but YAML is only used for spec tests so we do this
 	// rather than maintain a custom YAML unmarshaller.
-	var data beaconBlockJSON
-	if err := yaml.Unmarshal(input, &data); err != nil {
+	var unmarshaled beaconBlockJSON
+	if err := yaml.Unmarshal(input, &unmarshaled); err != nil {
 		return errors.Wrap(err, "failed to unmarshal YAML")
 	}
-	bytes, err := json.Marshal(data)
+	marshaled, err := json.Marshal(unmarshaled)
 	if err != nil {
 		return errors.Wrap(err, "failed to marshal JSON")
 	}
 
-	return b.UnmarshalJSON(bytes)
+	return b.UnmarshalJSON(marshaled)
 }
diff --git a/spec/deneb/beaconblockbody_yaml.go b/spec/deneb/beaconblockbody_yaml.go
index b040e59a..8b79a4b6 100644
--- a/spec/deneb/beaconblockbody_yaml.go
+++ b/spec/deneb/beaconblockbody_yaml.go
@@ -73,14 +73,14 @@ func (b *BeaconBlockBody) MarshalYAML() ([]byte, error) {
 func (b *BeaconBlockBody) UnmarshalYAML(input []byte) error {
 	// This is very inefficient, but YAML is only used for spec tests so we do this
 	// rather than maintain a custom YAML unmarshaller.
-	var data beaconBlockBodyJSON
-	if err := yaml.Unmarshal(input, &data); err != nil {
+	var unmarshaled beaconBlockBodyJSON
+	if err := yaml.Unmarshal(input, &unmarshaled); err != nil {
 		return errors.Wrap(err, "failed to unmarshal YAML")
 	}
-	bytes, err := json.Marshal(data)
+	marshaled, err := json.Marshal(unmarshaled)
 	if err != nil {
 		return errors.Wrap(err, "failed to marshal JSON")
 	}
 
-	return b.UnmarshalJSON(bytes)
+	return b.UnmarshalJSON(marshaled)
 }
diff --git a/spec/deneb/beaconstate_yaml.go b/spec/deneb/beaconstate_yaml.go
index d33b6a76..b520707b 100644
--- a/spec/deneb/beaconstate_yaml.go
+++ b/spec/deneb/beaconstate_yaml.go
@@ -100,14 +100,14 @@ func (b *BeaconState) MarshalYAML() ([]byte, error) {
 func (b *BeaconState) UnmarshalYAML(input []byte) error {
 	// This is very inefficient, but YAML is only used for spec tests so we do this
 	// rather than maintain a custom YAML unmarshaller.
-	var data beaconStateJSON
-	if err := yaml.Unmarshal(input, &data); err != nil {
+	var unmarshaled beaconStateJSON
+	if err := yaml.Unmarshal(input, &unmarshaled); err != nil {
 		return errors.Wrap(err, "failed to unmarshal YAML")
 	}
-	bytes, err := json.Marshal(data)
+	marshaled, err := json.Marshal(unmarshaled)
 	if err != nil {
 		return errors.Wrap(err, "failed to marshal JSON")
 	}
 
-	return b.UnmarshalJSON(bytes)
+	return b.UnmarshalJSON(marshaled)
 }
diff --git a/spec/deneb/blob.go b/spec/deneb/blob.go
index 02353429..e4587630 100644
--- a/spec/deneb/blob.go
+++ b/spec/deneb/blob.go
@@ -58,7 +58,7 @@ func (b *Blob) UnmarshalJSON(input []byte) error {
 		return errors.New("invalid prefix")
 	}
 	if !bytes.HasSuffix(input, []byte{'"'}) {
-		return errors.New("Invalid suffix")
+		return errors.New("invalid suffix")
 	}
 	if len(input) != 1+2+BlobLength*2+1 {
 		return errors.New("incorrect length")
@@ -91,7 +91,7 @@ func (b *Blob) UnmarshalYAML(input []byte) error {
 		return errors.New("invalid prefix")
 	}
 	if !bytes.HasSuffix(input, []byte{'\''}) {
-		return errors.New("Invalid suffix")
+		return errors.New("invalid suffix")
 	}
 	if len(input) != 1+2+BlobLength*2+1 {
 		return errors.New("incorrect length")
diff --git a/spec/deneb/blobidentifier_yaml.go b/spec/deneb/blobidentifier_yaml.go
index b48f0e68..0e628175 100644
--- a/spec/deneb/blobidentifier_yaml.go
+++ b/spec/deneb/blobidentifier_yaml.go
@@ -44,14 +44,14 @@ func (b *BlobIdentifier) MarshalYAML() ([]byte, error) {
 func (b *BlobIdentifier) UnmarshalYAML(input []byte) error {
 	// This is very inefficient, but YAML is only used for spec tests so we do this
 	// rather than maintain a custom YAML unmarshaller.
-	var data blobIdentifierJSON
-	if err := yaml.Unmarshal(input, &data); err != nil {
+	var unmarshaled blobIdentifierJSON
+	if err := yaml.Unmarshal(input, &unmarshaled); err != nil {
 		return errors.Wrap(err, "failed to unmarshal YAML")
 	}
-	bytes, err := json.Marshal(data)
+	marshaled, err := json.Marshal(unmarshaled)
 	if err != nil {
 		return errors.Wrap(err, "failed to marshal JSON")
 	}
 
-	return b.UnmarshalJSON(bytes)
+	return b.UnmarshalJSON(marshaled)
 }
diff --git a/spec/deneb/blobsidecar_yaml.go b/spec/deneb/blobsidecar_yaml.go
index 1610217d..b6df70a5 100644
--- a/spec/deneb/blobsidecar_yaml.go
+++ b/spec/deneb/blobsidecar_yaml.go
@@ -53,14 +53,14 @@ func (b *BlobSidecar) MarshalYAML() ([]byte, error) {
 func (b *BlobSidecar) UnmarshalYAML(input []byte) error {
 	// This is very inefficient, but YAML is only used for spec tests so we do this
 	// rather than maintain a custom YAML unmarshaller.
-	var data blobSidecarJSON
-	if err := yaml.Unmarshal(input, &data); err != nil {
+	var unmarshaled blobSidecarJSON
+	if err := yaml.Unmarshal(input, &unmarshaled); err != nil {
 		return errors.Wrap(err, "failed to unmarshal YAML")
 	}
-	bytes, err := json.Marshal(&data)
+	marshaled, err := json.Marshal(&unmarshaled)
 	if err != nil {
 		return errors.Wrap(err, "failed to marshal JSON")
 	}
 
-	return b.UnmarshalJSON(bytes)
+	return b.UnmarshalJSON(marshaled)
 }
diff --git a/spec/deneb/executionpayload_yaml.go b/spec/deneb/executionpayload_yaml.go
index a397202a..186fce8a 100644
--- a/spec/deneb/executionpayload_yaml.go
+++ b/spec/deneb/executionpayload_yaml.go
@@ -86,14 +86,14 @@ func (e *ExecutionPayload) MarshalYAML() ([]byte, error) {
 func (e *ExecutionPayload) UnmarshalYAML(input []byte) error {
 	// This is very inefficient, but YAML is only used for spec tests so we do this
 	// rather than maintain a custom YAML unmarshaller.
-	var data executionPayloadJSON
-	if err := yaml.Unmarshal(input, &data); err != nil {
+	var unmarshaled executionPayloadJSON
+	if err := yaml.Unmarshal(input, &unmarshaled); err != nil {
 		return errors.Wrap(err, "failed to unmarshal YAML")
 	}
-	bytes, err := json.Marshal(data)
+	marshaled, err := json.Marshal(unmarshaled)
 	if err != nil {
 		return errors.Wrap(err, "failed to marshal JSON")
 	}
 
-	return e.UnmarshalJSON(bytes)
+	return e.UnmarshalJSON(marshaled)
 }
diff --git a/spec/deneb/executionpayloadheader_yaml.go b/spec/deneb/executionpayloadheader_yaml.go
index 1d49a2f4..cd0b6265 100644
--- a/spec/deneb/executionpayloadheader_yaml.go
+++ b/spec/deneb/executionpayloadheader_yaml.go
@@ -82,14 +82,14 @@ func (e *ExecutionPayloadHeader) MarshalYAML() ([]byte, error) {
 func (e *ExecutionPayloadHeader) UnmarshalYAML(input []byte) error {
 	// This is very inefficient, but YAML is only used for spec tests so we do this
 	// rather than maintain a custom YAML unmarshaller.
-	var data executionPayloadHeaderJSON
-	if err := yaml.Unmarshal(input, &data); err != nil {
+	var unmarshaled executionPayloadHeaderJSON
+	if err := yaml.Unmarshal(input, &unmarshaled); err != nil {
 		return errors.Wrap(err, "failed to unmarshal YAML")
 	}
-	bytes, err := json.Marshal(data)
+	marshaled, err := json.Marshal(unmarshaled)
 	if err != nil {
 		return errors.Wrap(err, "failed to marshal JSON")
 	}
 
-	return e.UnmarshalJSON(bytes)
+	return e.UnmarshalJSON(marshaled)
 }
diff --git a/testclients/erroring.go b/testclients/erroring.go
index f1b355b6..a2c86cfd 100644
--- a/testclients/erroring.go
+++ b/testclients/erroring.go
@@ -71,12 +71,12 @@ func (s *Erroring) Address() string {
 }
 
 // IsActive returns true if the client is active.
-func (s *Erroring) IsActive() bool {
+func (*Erroring) IsActive() bool {
 	return true
 }
 
 // IsSynced returns true if the client is synced.
-func (s *Erroring) IsSynced() bool {
+func (*Erroring) IsSynced() bool {
 	return true
 }
 
@@ -639,7 +639,7 @@ func (s *Erroring) SyncCommitteeDuties(ctx context.Context, opts *api.SyncCommit
 }
 
 // Spec provides the spec information of the chain.
-func (s *Erroring) Spec(ctx context.Context, opts *api.SpecOpts) (*api.Response[map[string]interface{}], error) {
+func (s *Erroring) Spec(ctx context.Context, opts *api.SpecOpts) (*api.Response[map[string]any], error) {
 	if err := s.maybeError(ctx); err != nil {
 		return nil, err
 	}
diff --git a/testclients/sleepy.go b/testclients/sleepy.go
index 277f445a..88acec9c 100644
--- a/testclients/sleepy.go
+++ b/testclients/sleepy.go
@@ -72,12 +72,12 @@ func (s *Sleepy) Address() string {
 }
 
 // IsActive returns true if the client is active.
-func (s *Sleepy) IsActive() bool {
+func (*Sleepy) IsActive() bool {
 	return true
 }
 
 // IsSynced returns true if the client is synced.
-func (s *Sleepy) IsSynced() bool {
+func (*Sleepy) IsSynced() bool {
 	return true
 }
 
@@ -463,7 +463,7 @@ func (s *Sleepy) ProposerDuties(ctx context.Context,
 }
 
 // Spec provides the spec information of the chain.
-func (s *Sleepy) Spec(ctx context.Context, opts *api.SpecOpts) (*api.Response[map[string]interface{}], error) {
+func (s *Sleepy) Spec(ctx context.Context, opts *api.SpecOpts) (*api.Response[map[string]any], error) {
 	s.sleep(ctx)
 	next, isNext := s.next.(consensusclient.SpecProvider)
 	if !isNext {