diff --git a/.github/workflows/nix.yml b/.github/workflows/nix.yml
index 4fc4fc4..ebb00aa 100644
--- a/.github/workflows/nix.yml
+++ b/.github/workflows/nix.yml
@@ -27,4 +27,6 @@ jobs:
           authToken: '${{ secrets.CACHIX_AUTH_TOKEN }}'
       - name: Build
         run: nix build
+      - name: Check
+        run: nix flake check -L
 
diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index 29b6dff..4edbf83 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -9,7 +9,6 @@ on:
   schedule:
     - cron: '0 1 * * *'
 
-
 jobs:
   stable-idris:
     runs-on: ubuntu-latest
@@ -28,12 +27,9 @@ jobs:
           idris2 --version
           echo ''
           make
-      - name: Check Executable
-        run: |
-          ./harmony help > output.txt
-          git diff --no-index -- test/expected_help.txt output.txt
-#      - name: Test
-#        run: make test
+      - name: Test
+        shell: bash
+        run: INTERACTIVE='' make test
 
   nightly-idris:
     runs-on: ubuntu-latest
@@ -52,10 +48,7 @@ jobs:
           idris2 --version
           echo ''
           make
-      - name: Check Executable
-        run: |
-          ./harmony help > output.txt
-          git diff --no-index -- test/expected_help.txt output.txt
-#      - name: Test
-#        run: make test
+      - name: Test
+        shell: bash
+        run: INTERACTIVE='' make test
 
diff --git a/.gitignore b/.gitignore
index f60b4de..c3c8bd4 100644
--- a/.gitignore
+++ b/.gitignore
@@ -14,3 +14,5 @@ harmony-npm.tar.gz
 *.idr~
 
 result
+
+test/**/output
diff --git a/Makefile b/Makefile
index d6f6ed2..559dd12 100644
--- a/Makefile
+++ b/Makefile
@@ -21,7 +21,7 @@ else
 	ised = sed -I ''
 endif
 
-.PHONY: all build nix-build install package publish clean version
+.PHONY: all build test nix-build install package publish clean version
 
 all: build
 
@@ -147,6 +147,9 @@ publish : package
 install: harmony
 	npm install --global
 
+test:
+	$(MAKE) -C test test
+
 clean:
 	rm -rf ./depends
 	rm -rf ./build
@@ -154,3 +157,4 @@ clean:
 	rm -rf ./harmony-npm
 	rm -f ./harmony
 	rm -f ./harmony-npm.tar.gz
+	$(MAKE) -C test clean
diff --git a/default.nix b/default.nix
index 1cb903c..62e00f7 100644
--- a/default.nix
+++ b/default.nix
@@ -94,6 +94,11 @@
         --zsh <($out/bin/harmony --zsh-completion-script) \
     '';
 
+    installCheckPhase = ''
+      export harmony=$out/bin/harmony
+      INTERACTIVE="" make test
+    '';
+
     meta = with lib; {
       description = "Harmony GitHub collaboration tool";
       homepage = "https://github.com/mattpolzin/harmony";
diff --git a/flake.nix b/flake.nix
index b35079f..df69fa6 100644
--- a/flake.nix
+++ b/flake.nix
@@ -28,6 +28,13 @@
         default = self.packages.${system}.harmony;
       }
     );
+    checks = forAllSystems (
+      system: let
+        harmony = self.packages.${system}.harmony;
+      in {
+        tests = harmony.overrideAttrs { doInstallCheck = true; };
+      }
+    );
     devShells = forAllSystems (
       system: let
         pkgs = nixpkgs.legacyPackages.${system};
diff --git a/test/Makefile b/test/Makefile
new file mode 100644
index 0000000..6be0ac6
--- /dev/null
+++ b/test/Makefile
@@ -0,0 +1,19 @@
+
+PWD = $(shell pwd)
+harmony ?= $(shell realpath "${PWD}/../harmony")
+
+.PHONY: test clean
+
+INTERACTIVE ?= "--interactive"
+
+IDR_SOURCES := $(wildcard *.idr)
+
+build/exec/test: $(IDR_SOURCES)
+	idris2 --build harmony-tests.ipkg
+
+export harmony
+test: build/exec/test
+	build/exec/test runtests $(INTERACTIVE)
+
+clean:
+	rm -rf ./test/build
diff --git a/test/Test.idr b/test/Test.idr
new file mode 100644
index 0000000..ad96b60
--- /dev/null
+++ b/test/Test.idr
@@ -0,0 +1,64 @@
+module Test
+
+import Data.SnocList
+import Data.String
+import Test.Golden
+import System.File
+import System
+
+%default total
+
+splitOn : (sbustr : String) -> String -> Maybe (String, String)
+splitOn substr str = 
+  let sub = unpack substr
+  in mapHom pack <$> go sub sub [<] [<] (unpack str)
+  where
+    go : (fullSubstr : List Char) -> (remainingToMatch : List Char) -> (beforeMatch : SnocList Char) -> (throughMatch : SnocList Char) -> List Char -> Maybe (List Char, List Char)
+    go fullSubstr [] beforeMatch throughMatch cs = Just (cast beforeMatch, cs)
+    go fullSubstr (x :: xs) beforeMatch throughMatch [] = Nothing
+    go fullSubstr (x :: xs) beforeMatch throughMatch (y :: ys) =
+      if x == y
+         then go fullSubstr xs beforeMatch (throughMatch :< y) ys
+         else go fullSubstr fullSubstr (throughMatch :< y) (throughMatch :< y) ys
+
+req : List Requirement
+req = []
+
+mkTests : List String -> TestPool
+mkTests = MkTestPool "Misc"
+                  req
+                  Nothing
+
+misc : TestPool
+misc = mkTests
+  [ "help-command"
+  ]
+
+configTests : IO TestPool
+configTests = testsInDir "config-command" "Config Command"
+
+||| We want to avoid Harmony performing a sync as part of tests that read the
+||| test configuration file so we mark the configuration file as updated.
+covering
+markConfigsAsUpdated : IO ()
+markConfigsAsUpdated = do
+  Right config <- readFile "./config-command/harmony.json"
+    | Left e => die (show e)
+  let Just (before, after) = splitOn #""updatedAt":"# config
+    | Nothing => die "could not update config timestamp"
+  let (_, rest) = break (\c => c == ',' || c == '}') after
+  let ts = show !time
+  let config' = before ++ "\"updatedAt\":" ++ ts ++ rest
+  Right _ <- writeFile "./config-command/harmony.json" config'
+    | Left e => die (show e)
+  pure ()
+
+covering
+main : IO ()
+main = do
+  markConfigsAsUpdated
+  runner
+    [ misc
+    , !configTests
+    ]
+
diff --git a/test/config-command/cleanup.sh b/test/config-command/cleanup.sh
new file mode 100644
index 0000000..4c22f87
--- /dev/null
+++ b/test/config-command/cleanup.sh
@@ -0,0 +1,2 @@
+
+rm ./harmony.json
diff --git a/test/config-command/harmony.json b/test/config-command/harmony.json
new file mode 100644
index 0000000..322df9a
--- /dev/null
+++ b/test/config-command/harmony.json
@@ -0,0 +1 @@
+{"requestTeams":true,"requestUsers":false,"commentOnRequest":"at-mention","org":"mattpolzin","repo":"harmony","defaultRemote":"origin","mainBranch":"main","theme":"dark","orgMembers":[],"teamSlugs":[],"repoLabels":["WIP","bug","documentation","duplicate","enhancement","good first issue","help wanted","invalid","question","wontfix"],"ignoredPRs":[],"githubPAT":null,"updatedAt":1720239789}
\ No newline at end of file
diff --git a/test/config-command/no-args/expected b/test/config-command/no-args/expected
new file mode 100644
index 0000000..8c0051f
--- /dev/null
+++ b/test/config-command/no-args/expected
@@ -0,0 +1,9 @@
+The config command expects one or two arguments. Specify a property to read it out or specify both a property and a value to set it to.
+
+requestTeams:     [true/false] Determines whether or not to request reviews from teams when requesting individual reviewers from a team.
+requestUsers:     [true/false] Determines whether or not to request reviews from an individual user based on Harmony's heuristics when requestin review from teams. You might want to disable `requestUsers` to allow GitHub to pick users to request based on the team. This setting does not affect the ability to request reviews from individual users withe Harmony's `+<username>` syntax.
+commentOnRequest: [none/name/at-mention] Determines whether- and how to comment on PR indicating that Harmony chose a reviewer.
+defaultRemote:    [string]     The name of the default Git remote to use (e.g. 'origin').
+mainBranch:       [string]     The name of the default Git base branch for new PRs.
+theme:            [dark/light]
+githubPAT:        [string]     The Personal Access Token Harmony should use to authenticate with GitHub. You can leave this unset if you want to set a PAT via the GITHUB_PAT environment variable.
diff --git a/test/config-command/no-args/run b/test/config-command/no-args/run
new file mode 100644
index 0000000..a83da95
--- /dev/null
+++ b/test/config-command/no-args/run
@@ -0,0 +1,8 @@
+. ../../setup.sh
+. ../setup.sh
+
+set +e
+
+$harmony config 2>&1
+
+. ../cleanup.sh
diff --git a/test/config-command/no-request-warning/expected b/test/config-command/no-request-warning/expected
new file mode 100644
index 0000000..fe89ffc
--- /dev/null
+++ b/test/config-command/no-request-warning/expected
@@ -0,0 +1,2 @@
+`requestUsers` and `requestTeams` are both False. This means `harmony request` commands will only ever request reviews from users that are specified with the `+<userlogin>` syntax. More commonly, you want Harmony to at least request review for either a team or a user from a team when you say `harmony request teamname`; It's suggested to either `harmony config requestUsers true` or `harmony config requestTeams true` (or both).
+
diff --git a/test/config-command/no-request-warning/run b/test/config-command/no-request-warning/run
new file mode 100644
index 0000000..e4437d2
--- /dev/null
+++ b/test/config-command/no-request-warning/run
@@ -0,0 +1,6 @@
+. ../../setup.sh
+. ../setup.sh
+
+${harmony} config requestTeams no
+
+. ../cleanup.sh
diff --git a/test/config-command/read-args/expected b/test/config-command/read-args/expected
new file mode 100644
index 0000000..43deed1
--- /dev/null
+++ b/test/config-command/read-args/expected
@@ -0,0 +1,7 @@
+False
+True
+at-mention
+"origin"
+"main"
+dark
+Not set (will use $GITHUB_PAT environment variable)
diff --git a/test/config-command/read-args/run b/test/config-command/read-args/run
new file mode 100644
index 0000000..52517f9
--- /dev/null
+++ b/test/config-command/read-args/run
@@ -0,0 +1,14 @@
+. ../../setup.sh
+. ../setup.sh
+
+keys="requestUsers
+requestTeams
+commentOnRequest
+defaultRemote
+mainBranch
+theme
+githubPAT"
+
+echo $keys | xargs -n1 ${harmony} config
+
+. ../cleanup.sh
diff --git a/test/config-command/setup.sh b/test/config-command/setup.sh
new file mode 100644
index 0000000..9cf5fbc
--- /dev/null
+++ b/test/config-command/setup.sh
@@ -0,0 +1,2 @@
+
+cp ../harmony.json ./harmony.json
diff --git a/test/config-command/write-args/expected b/test/config-command/write-args/expected
new file mode 100644
index 0000000..50a827b
--- /dev/null
+++ b/test/config-command/write-args/expected
@@ -0,0 +1,7 @@
+True
+False
+name
+"upstream"
+"root"
+light
+xxxxxxxx (hidden)
diff --git a/test/config-command/write-args/run b/test/config-command/write-args/run
new file mode 100644
index 0000000..7c069d3
--- /dev/null
+++ b/test/config-command/write-args/run
@@ -0,0 +1,25 @@
+. ../../setup.sh
+. ../setup.sh
+
+${harmony} config requestUsers yes
+${harmony} config requestUsers
+
+${harmony} config requestTeams no
+${harmony} config requestTeams
+
+${harmony} config commentOnRequest name
+${harmony} config commentOnRequest
+
+${harmony} config defaultRemote upstream
+${harmony} config defaultRemote
+
+${harmony} config mainBranch root
+${harmony} config mainBranch
+
+${harmony} config theme light
+${harmony} config theme
+
+${harmony} config githubPAT 1234ABCD
+${harmony} config githubPAT
+
+. ../cleanup.sh
diff --git a/test/harmony-tests.ipkg b/test/harmony-tests.ipkg
new file mode 100644
index 0000000..77b5a15
--- /dev/null
+++ b/test/harmony-tests.ipkg
@@ -0,0 +1,47 @@
+package harmony-tests
+-- version =
+authors = "Mathew Polzin"
+-- maintainers =
+-- license =
+-- brief =
+-- readme =
+-- homepage =
+-- sourceloc =
+-- bugtracker =
+
+-- the Idris2 version required (e.g. langversion >= 0.5.1)
+-- langversion
+
+-- packages to add to search path
+depends = test
+
+-- modules to install
+-- modules =
+
+-- main file (i.e. file to load at REPL)
+main = Test
+
+-- name of executable
+executable = test
+-- opts =
+-- sourcedir =
+-- builddir =
+-- outputdir =
+
+-- script to run before building
+-- prebuild =
+
+-- script to run after building
+-- postbuild =
+
+-- script to run after building, before installing
+-- preinstall =
+
+-- script to run after installing
+-- postinstall =
+
+-- script to run before cleaning
+-- preclean =
+
+-- script to run after cleaning
+-- postclean =
diff --git a/test/expected_help.txt b/test/help-command/expected
similarity index 100%
rename from test/expected_help.txt
rename to test/help-command/expected
diff --git a/test/help-command/run b/test/help-command/run
new file mode 100644
index 0000000..b160aff
--- /dev/null
+++ b/test/help-command/run
@@ -0,0 +1,3 @@
+. ../setup.sh
+
+$harmony help
diff --git a/test/setup.sh b/test/setup.sh
new file mode 100644
index 0000000..8b13789
--- /dev/null
+++ b/test/setup.sh
@@ -0,0 +1 @@
+