diff --git a/exercises/practice/custom-set/.docs/instructions.md b/exercises/practice/custom-set/.docs/instructions.md
index e4931b058..33b90e28d 100644
--- a/exercises/practice/custom-set/.docs/instructions.md
+++ b/exercises/practice/custom-set/.docs/instructions.md
@@ -2,7 +2,6 @@
 
 Create a custom set type.
 
-Sometimes it is necessary to define a custom data structure of some
-type, like a set. In this exercise you will define your own set. How it
-works internally doesn't matter, as long as it behaves like a set of
-unique elements.
+Sometimes it is necessary to define a custom data structure of some type, like a set.
+In this exercise you will define your own set.
+How it works internally doesn't matter, as long as it behaves like a set of unique elements.
diff --git a/exercises/practice/custom-set/.meta/test_template.tera b/exercises/practice/custom-set/.meta/test_template.tera
new file mode 100644
index 000000000..c6fc07bb5
--- /dev/null
+++ b/exercises/practice/custom-set/.meta/test_template.tera
@@ -0,0 +1,60 @@
+use custom_set::CustomSet;
+{% for test in cases %}
+#[test]
+{% if loop.index != 1 -%}
+#[ignore]
+{% endif -%}
+fn {{ test.description | slugify | replace(from="-", to="_") }}() {
+{%- if test.property == "empty" %}
+    let set = CustomSet::<i32>::new(&{{ test.input.set | json_encode() }});
+    assert!(
+        {%- if not test.expected -%} ! {%- endif -%}
+        set.is_empty());
+{%- elif test.property == "contains" %}
+    let set = CustomSet::<i32>::new(&{{ test.input.set | json_encode() }});
+    assert!(
+        {%- if not test.expected -%} ! {%- endif -%}
+        set.contains(&{{ test.input.element }}));
+{%- elif test.property == "subset" %}
+    let set_1 = CustomSet::<i32>::new(&{{ test.input.set1 | json_encode() }});
+    let set_2 = CustomSet::<i32>::new(&{{ test.input.set2 | json_encode() }});
+    assert!(
+        {%- if not test.expected -%} ! {%- endif -%}
+        set_1.is_subset(&set_2));
+{%- elif test.property == "disjoint" %}
+    let set_1 = CustomSet::<i32>::new(&{{ test.input.set1 | json_encode() }});
+    let set_2 = CustomSet::<i32>::new(&{{ test.input.set2 | json_encode() }});
+    assert!(
+        {%- if not test.expected -%} ! {%- endif -%}
+        set_1.is_disjoint(&set_2));
+{%- elif test.property == "equal" %}
+    let set_1 = CustomSet::<i32>::new(&{{ test.input.set1 | json_encode() }});
+    let set_2 = CustomSet::<i32>::new(&{{ test.input.set2 | json_encode() }});
+    {% if test.expected -%}
+        assert_eq!(set_1, set_2);
+    {%- else -%}
+        assert_ne!(set_1, set_2);
+    {%- endif %}
+{%- elif test.property == "add" %}
+    let mut set = CustomSet::<i32>::new(&{{ test.input.set | json_encode() }});
+    set.add({{ test.input.element }});
+    let expected = CustomSet::<i32>::new(&{{ test.expected | json_encode() }});
+    assert_eq!(set, expected);
+{%- elif test.property == "intersection" %}
+    let set_1 = CustomSet::<i32>::new(&{{ test.input.set1 | json_encode() }});
+    let set_2 = CustomSet::<i32>::new(&{{ test.input.set2 | json_encode() }});
+    let expected = CustomSet::<i32>::new(&{{ test.expected | json_encode() }});
+    assert_eq!(set_1.intersection(&set_2), expected);
+{%- elif test.property == "difference" %}
+    let set_1 = CustomSet::<i32>::new(&{{ test.input.set1 | json_encode() }});
+    let set_2 = CustomSet::<i32>::new(&{{ test.input.set2 | json_encode() }});
+    let expected = CustomSet::<i32>::new(&{{ test.expected | json_encode() }});
+    assert_eq!(set_1.difference(&set_2), expected);
+{%- elif test.property == "union" %}
+    let set_1 = CustomSet::<i32>::new(&{{ test.input.set1 | json_encode() }});
+    let set_2 = CustomSet::<i32>::new(&{{ test.input.set2 | json_encode() }});
+    let expected = CustomSet::<i32>::new(&{{ test.expected | json_encode() }});
+    assert_eq!(set_1.union(&set_2), expected);
+{%- endif %}
+}
+{% endfor -%}
diff --git a/exercises/practice/custom-set/.meta/tests.toml b/exercises/practice/custom-set/.meta/tests.toml
index 1f3929e49..8c450e0ba 100644
--- a/exercises/practice/custom-set/.meta/tests.toml
+++ b/exercises/practice/custom-set/.meta/tests.toml
@@ -1,30 +1,127 @@
-# This is an auto-generated file. Regular comments will be removed when this
-# file is regenerated. Regenerating will not touch any manually added keys,
-# so comments can be added in a "comment" key.
+# This is an auto-generated file.
+#
+# Regenerating this file via `configlet sync` will:
+# - Recreate every `description` key/value pair
+# - Recreate every `reimplements` key/value pair, where they exist in problem-specifications
+# - Remove any `include = true` key/value pair (an omitted `include` key implies inclusion)
+# - Preserve any other key/value pair
+#
+# As user-added comments (using the # character) will be removed when this file
+# is regenerated, comments can be added via a `comment` key.
 
 [20c5f855-f83a-44a7-abdd-fe75c6cf022b]
-description = "sets with no elements are empty"
+description = "Returns true if the set contains no elements -> sets with no elements are empty"
 
 [d506485d-5706-40db-b7d8-5ceb5acf88d2]
-description = "sets with elements are not empty"
+description = "Returns true if the set contains no elements -> sets with elements are not empty"
 
 [759b9740-3417-44c3-8ca3-262b3c281043]
-description = "nothing is contained in an empty set"
+description = "Sets can report if they contain an element -> nothing is contained in an empty set"
+
+[f83cd2d1-2a85-41bc-b6be-80adbff4be49]
+description = "Sets can report if they contain an element -> when the element is in the set"
+
+[93423fc0-44d0-4bc0-a2ac-376de8d7af34]
+description = "Sets can report if they contain an element -> when the element is not in the set"
+
+[c392923a-637b-4495-b28e-34742cd6157a]
+description = "A set is a subset if all of its elements are contained in the other set -> empty set is a subset of another empty set"
+
+[5635b113-be8c-4c6f-b9a9-23c485193917]
+description = "A set is a subset if all of its elements are contained in the other set -> empty set is a subset of non-empty set"
+
+[832eda58-6d6e-44e2-92c2-be8cf0173cee]
+description = "A set is a subset if all of its elements are contained in the other set -> non-empty set is not a subset of empty set"
+
+[c830c578-8f97-4036-b082-89feda876131]
+description = "A set is a subset if all of its elements are contained in the other set -> set is a subset of set with exact same elements"
+
+[476a4a1c-0fd1-430f-aa65-5b70cbc810c5]
+description = "A set is a subset if all of its elements are contained in the other set -> set is a subset of larger set with same elements"
+
+[d2498999-3e46-48e4-9660-1e20c3329d3d]
+description = "A set is a subset if all of its elements are contained in the other set -> set is not a subset of set that does not contain its elements"
+
+[7d38155e-f472-4a7e-9ad8-5c1f8f95e4cc]
+description = "Sets are disjoint if they share no elements -> the empty set is disjoint with itself"
+
+[7a2b3938-64b6-4b32-901a-fe16891998a6]
+description = "Sets are disjoint if they share no elements -> empty set is disjoint with non-empty set"
+
+[589574a0-8b48-48ea-88b0-b652c5fe476f]
+description = "Sets are disjoint if they share no elements -> non-empty set is disjoint with empty set"
+
+[febeaf4f-f180-4499-91fa-59165955a523]
+description = "Sets are disjoint if they share no elements -> sets are not disjoint if they share an element"
+
+[0de20d2f-c952-468a-88c8-5e056740f020]
+description = "Sets are disjoint if they share no elements -> sets are disjoint if they share no elements"
 
 [4bd24adb-45da-4320-9ff6-38c044e9dff8]
-description = "empty sets are equal"
+description = "Sets with the same elements are equal -> empty sets are equal"
+
+[f65c0a0e-6632-4b2d-b82c-b7c6da2ec224]
+description = "Sets with the same elements are equal -> empty set is not equal to non-empty set"
+
+[81e53307-7683-4b1e-a30c-7e49155fe3ca]
+description = "Sets with the same elements are equal -> non-empty set is not equal to empty set"
 
 [d57c5d7c-a7f3-48cc-a162-6b488c0fbbd0]
-description = "sets with the same elements are equal"
+description = "Sets with the same elements are equal -> sets with the same elements are equal"
 
 [dd61bafc-6653-42cc-961a-ab071ee0ee85]
-description = "sets with different elements are not equal"
+description = "Sets with the same elements are equal -> sets with different elements are not equal"
+
+[06059caf-9bf4-425e-aaff-88966cb3ea14]
+description = "Sets with the same elements are equal -> set is not equal to larger set with same elements"
+
+[d4a1142f-09aa-4df9-8b83-4437dcf7ec24]
+description = "Sets with the same elements are equal -> set is equal to a set constructed from an array with duplicates"
 
 [8a677c3c-a658-4d39-bb88-5b5b1a9659f4]
-description = "add to empty set"
+description = "Unique elements can be added to a set -> add to empty set"
+
+[0903dd45-904d-4cf2-bddd-0905e1a8d125]
+description = "Unique elements can be added to a set -> add to non-empty set"
+
+[b0eb7bb7-5e5d-4733-b582-af771476cb99]
+description = "Unique elements can be added to a set -> adding an existing element does not change the set"
+
+[893d5333-33b8-4151-a3d4-8f273358208a]
+description = "Intersection returns a set of all shared elements -> intersection of two empty sets is an empty set"
+
+[d739940e-def2-41ab-a7bb-aaf60f7d782c]
+description = "Intersection returns a set of all shared elements -> intersection of an empty set and non-empty set is an empty set"
+
+[3607d9d8-c895-4d6f-ac16-a14956e0a4b7]
+description = "Intersection returns a set of all shared elements -> intersection of a non-empty set and an empty set is an empty set"
 
 [b5120abf-5b5e-41ab-aede-4de2ad85c34e]
-description = "intersection of two sets with no shared elements is an empty set"
+description = "Intersection returns a set of all shared elements -> intersection of two sets with no shared elements is an empty set"
 
 [af21ca1b-fac9-499c-81c0-92a591653d49]
-description = "intersection of two sets with shared elements is a set of the shared elements"
+description = "Intersection returns a set of all shared elements -> intersection of two sets with shared elements is a set of the shared elements"
+
+[c5e6e2e4-50e9-4bc2-b89f-c518f015b57e]
+description = "Difference (or Complement) of a set is a set of all elements that are only in the first set -> difference of two empty sets is an empty set"
+
+[2024cc92-5c26-44ed-aafd-e6ca27d6fcd2]
+description = "Difference (or Complement) of a set is a set of all elements that are only in the first set -> difference of empty set and non-empty set is an empty set"
+
+[e79edee7-08aa-4c19-9382-f6820974b43e]
+description = "Difference (or Complement) of a set is a set of all elements that are only in the first set -> difference of a non-empty set and an empty set is the non-empty set"
+
+[c5ac673e-d707-4db5-8d69-7082c3a5437e]
+description = "Difference (or Complement) of a set is a set of all elements that are only in the first set -> difference of two non-empty sets is a set of elements that are only in the first set"
+
+[c45aed16-5494-455a-9033-5d4c93589dc6]
+description = "Union returns a set of all elements in either set -> union of empty sets is an empty set"
+
+[9d258545-33c2-4fcb-a340-9f8aa69e7a41]
+description = "Union returns a set of all elements in either set -> union of an empty set and non-empty set is the non-empty set"
+
+[3aade50c-80c7-4db8-853d-75bac5818b83]
+description = "Union returns a set of all elements in either set -> union of a non-empty set and empty set is the non-empty set"
+
+[a00bb91f-c4b4-4844-8f77-c73e2e9df77c]
+description = "Union returns a set of all elements in either set -> union of non-empty sets contains all unique elements"
diff --git a/exercises/practice/custom-set/tests/custom-set.rs b/exercises/practice/custom-set/tests/custom-set.rs
index 10d384f22..6730dadb5 100644
--- a/exercises/practice/custom-set/tests/custom-set.rs
+++ b/exercises/practice/custom-set/tests/custom-set.rs
@@ -1,298 +1,323 @@
-use custom_set::*;
+use custom_set::CustomSet;
 
 #[test]
 fn sets_with_no_elements_are_empty() {
-    let set: CustomSet<()> = CustomSet::new(&[]);
+    let set = CustomSet::<i32>::new(&[]);
     assert!(set.is_empty());
 }
 
 #[test]
 #[ignore]
 fn sets_with_elements_are_not_empty() {
-    let set = CustomSet::new(&[1]);
+    let set = CustomSet::<i32>::new(&[1]);
     assert!(!set.is_empty());
 }
 
 #[test]
 #[ignore]
 fn nothing_is_contained_in_an_empty_set() {
-    let set = CustomSet::new(&[]);
+    let set = CustomSet::<i32>::new(&[]);
     assert!(!set.contains(&1));
 }
 
 #[test]
 #[ignore]
-fn true_when_the_element_is_in_the_set() {
-    let set = CustomSet::new(&[1, 2, 3]);
+fn when_the_element_is_in_the_set() {
+    let set = CustomSet::<i32>::new(&[1, 2, 3]);
     assert!(set.contains(&1));
 }
 
 #[test]
 #[ignore]
-fn false_when_the_element_is_not_in_the_set() {
-    let set = CustomSet::new(&[1, 2, 3]);
+fn when_the_element_is_not_in_the_set() {
+    let set = CustomSet::<i32>::new(&[1, 2, 3]);
     assert!(!set.contains(&4));
 }
 
 #[test]
 #[ignore]
-fn empty_sets_are_subsets_of_each_other() {
-    let set1: CustomSet<()> = CustomSet::new(&[]);
-    let set2: CustomSet<()> = CustomSet::new(&[]);
-    assert!(set1.is_subset(&set2));
-    assert!(set2.is_subset(&set1));
+fn empty_set_is_a_subset_of_another_empty_set() {
+    let set_1 = CustomSet::<i32>::new(&[]);
+    let set_2 = CustomSet::<i32>::new(&[]);
+    assert!(set_1.is_subset(&set_2));
 }
 
 #[test]
 #[ignore]
-fn empty_set_is_subset_of_non_empty_set() {
-    let set1 = CustomSet::new(&[]);
-    let set2 = CustomSet::new(&[1]);
-    assert!(set1.is_subset(&set2));
+fn empty_set_is_a_subset_of_non_empty_set() {
+    let set_1 = CustomSet::<i32>::new(&[]);
+    let set_2 = CustomSet::<i32>::new(&[1]);
+    assert!(set_1.is_subset(&set_2));
 }
 
 #[test]
 #[ignore]
-fn non_empty_set_is_not_subset_of_empty_set() {
-    let set1 = CustomSet::new(&[1]);
-    let set2 = CustomSet::new(&[]);
-    assert!(!set1.is_subset(&set2));
+fn non_empty_set_is_not_a_subset_of_empty_set() {
+    let set_1 = CustomSet::<i32>::new(&[1]);
+    let set_2 = CustomSet::<i32>::new(&[]);
+    assert!(!set_1.is_subset(&set_2));
 }
 
 #[test]
 #[ignore]
-fn sets_with_same_elements_are_subsets() {
-    let set1 = CustomSet::new(&[1, 2, 3]);
-    let set2 = CustomSet::new(&[1, 2, 3]);
-    assert!(set1.is_subset(&set2));
-    assert!(set2.is_subset(&set1));
+fn set_is_a_subset_of_set_with_exact_same_elements() {
+    let set_1 = CustomSet::<i32>::new(&[1, 2, 3]);
+    let set_2 = CustomSet::<i32>::new(&[1, 2, 3]);
+    assert!(set_1.is_subset(&set_2));
 }
 
 #[test]
 #[ignore]
-fn set_contained_in_other_set_is_a_subset() {
-    let set1 = CustomSet::new(&[1, 2, 3]);
-    let set2 = CustomSet::new(&[4, 1, 2, 3]);
-    assert!(set1.is_subset(&set2));
+fn set_is_a_subset_of_larger_set_with_same_elements() {
+    let set_1 = CustomSet::<i32>::new(&[1, 2, 3]);
+    let set_2 = CustomSet::<i32>::new(&[4, 1, 2, 3]);
+    assert!(set_1.is_subset(&set_2));
 }
 
 #[test]
 #[ignore]
-fn set_not_contained_in_other_set_is_not_a_subset_one() {
-    let set1 = CustomSet::new(&[1, 2, 3]);
-    let set2 = CustomSet::new(&[4, 1, 3]);
-    assert!(!set1.is_subset(&set2));
+fn set_is_not_a_subset_of_set_that_does_not_contain_its_elements() {
+    let set_1 = CustomSet::<i32>::new(&[1, 2, 3]);
+    let set_2 = CustomSet::<i32>::new(&[4, 1, 3]);
+    assert!(!set_1.is_subset(&set_2));
 }
 
 #[test]
 #[ignore]
-fn empty_sets_are_disjoint_with_each_other() {
-    let set1: CustomSet<()> = CustomSet::new(&[]);
-    let set2: CustomSet<()> = CustomSet::new(&[]);
-    assert!(set1.is_disjoint(&set2));
-    assert!(set2.is_disjoint(&set1));
+fn the_empty_set_is_disjoint_with_itself() {
+    let set_1 = CustomSet::<i32>::new(&[]);
+    let set_2 = CustomSet::<i32>::new(&[]);
+    assert!(set_1.is_disjoint(&set_2));
 }
 
 #[test]
 #[ignore]
-fn empty_set_disjoint_with_non_empty_set() {
-    let set1 = CustomSet::new(&[]);
-    let set2 = CustomSet::new(&[1]);
-    assert!(set1.is_disjoint(&set2));
+fn empty_set_is_disjoint_with_non_empty_set() {
+    let set_1 = CustomSet::<i32>::new(&[]);
+    let set_2 = CustomSet::<i32>::new(&[1]);
+    assert!(set_1.is_disjoint(&set_2));
 }
 
 #[test]
 #[ignore]
-fn non_empty_set_disjoint_with_empty_set() {
-    let set1 = CustomSet::new(&[1]);
-    let set2 = CustomSet::new(&[]);
-    assert!(set1.is_disjoint(&set2));
+fn non_empty_set_is_disjoint_with_empty_set() {
+    let set_1 = CustomSet::<i32>::new(&[1]);
+    let set_2 = CustomSet::<i32>::new(&[]);
+    assert!(set_1.is_disjoint(&set_2));
 }
 
 #[test]
 #[ignore]
-fn sets_with_one_element_in_common_are_not_disjoint() {
-    let set1 = CustomSet::new(&[1, 2]);
-    let set2 = CustomSet::new(&[2, 3]);
-    assert!(!set1.is_disjoint(&set2));
-    assert!(!set2.is_disjoint(&set1));
+fn sets_are_not_disjoint_if_they_share_an_element() {
+    let set_1 = CustomSet::<i32>::new(&[1, 2]);
+    let set_2 = CustomSet::<i32>::new(&[2, 3]);
+    assert!(!set_1.is_disjoint(&set_2));
 }
 
 #[test]
 #[ignore]
-fn sets_with_no_elements_in_common_are_disjoint() {
-    let set1 = CustomSet::new(&[1, 2]);
-    let set2 = CustomSet::new(&[3, 4]);
-    assert!(set1.is_disjoint(&set2));
-    assert!(set2.is_disjoint(&set1));
+fn sets_are_disjoint_if_they_share_no_elements() {
+    let set_1 = CustomSet::<i32>::new(&[1, 2]);
+    let set_2 = CustomSet::<i32>::new(&[3, 4]);
+    assert!(set_1.is_disjoint(&set_2));
 }
 
 #[test]
 #[ignore]
 fn empty_sets_are_equal() {
-    let set1: CustomSet<()> = CustomSet::new(&[]);
-    let set2: CustomSet<()> = CustomSet::new(&[]);
-    assert_eq!(set1, set2);
+    let set_1 = CustomSet::<i32>::new(&[]);
+    let set_2 = CustomSet::<i32>::new(&[]);
+    assert_eq!(set_1, set_2);
 }
 
 #[test]
 #[ignore]
-fn empty_set_is_not_equal_to_a_non_empty_set() {
-    let set1 = CustomSet::new(&[]);
-    let set2 = CustomSet::new(&[1, 2, 3]);
-    assert_ne!(set1, set2);
+fn empty_set_is_not_equal_to_non_empty_set() {
+    let set_1 = CustomSet::<i32>::new(&[]);
+    let set_2 = CustomSet::<i32>::new(&[1, 2, 3]);
+    assert_ne!(set_1, set_2);
 }
 
 #[test]
 #[ignore]
-fn non_empty_set_is_not_equal_to_an_empty_set() {
-    let set1 = CustomSet::new(&[1, 2, 3]);
-    let set2 = CustomSet::new(&[]);
-    assert_ne!(set1, set2);
+fn non_empty_set_is_not_equal_to_empty_set() {
+    let set_1 = CustomSet::<i32>::new(&[1, 2, 3]);
+    let set_2 = CustomSet::<i32>::new(&[]);
+    assert_ne!(set_1, set_2);
 }
 
 #[test]
 #[ignore]
 fn sets_with_the_same_elements_are_equal() {
-    let set1 = CustomSet::new(&[1, 2]);
-    let set2 = CustomSet::new(&[2, 1]);
-    assert_eq!(set1, set2);
+    let set_1 = CustomSet::<i32>::new(&[1, 2]);
+    let set_2 = CustomSet::<i32>::new(&[2, 1]);
+    assert_eq!(set_1, set_2);
 }
 
 #[test]
 #[ignore]
 fn sets_with_different_elements_are_not_equal() {
-    let set1 = CustomSet::new(&[1, 2, 3]);
-    let set2 = CustomSet::new(&[2, 1, 4]);
-    assert_ne!(set1, set2);
+    let set_1 = CustomSet::<i32>::new(&[1, 2, 3]);
+    let set_2 = CustomSet::<i32>::new(&[1, 2, 4]);
+    assert_ne!(set_1, set_2);
+}
+
+#[test]
+#[ignore]
+fn set_is_not_equal_to_larger_set_with_same_elements() {
+    let set_1 = CustomSet::<i32>::new(&[1, 2, 3]);
+    let set_2 = CustomSet::<i32>::new(&[1, 2, 3, 4]);
+    assert_ne!(set_1, set_2);
+}
+
+#[test]
+#[ignore]
+fn set_is_equal_to_a_set_constructed_from_an_array_with_duplicates() {
+    let set_1 = CustomSet::<i32>::new(&[1]);
+    let set_2 = CustomSet::<i32>::new(&[1, 1]);
+    assert_eq!(set_1, set_2);
 }
 
 #[test]
 #[ignore]
 fn add_to_empty_set() {
-    let mut set = CustomSet::new(&[]);
+    let mut set = CustomSet::<i32>::new(&[]);
     set.add(3);
-    assert_eq!(set, CustomSet::new(&[3]));
+    let expected = CustomSet::<i32>::new(&[3]);
+    assert_eq!(set, expected);
 }
 
 #[test]
 #[ignore]
 fn add_to_non_empty_set() {
-    let mut set = CustomSet::new(&[1, 2, 4]);
+    let mut set = CustomSet::<i32>::new(&[1, 2, 4]);
     set.add(3);
-    assert_eq!(set, CustomSet::new(&[1, 2, 3, 4]));
+    let expected = CustomSet::<i32>::new(&[1, 2, 3, 4]);
+    assert_eq!(set, expected);
 }
 
 #[test]
 #[ignore]
-fn add_existing_element() {
-    let mut set = CustomSet::new(&[1, 2, 3]);
+fn adding_an_existing_element_does_not_change_the_set() {
+    let mut set = CustomSet::<i32>::new(&[1, 2, 3]);
     set.add(3);
-    assert_eq!(set, CustomSet::new(&[1, 2, 3]));
+    let expected = CustomSet::<i32>::new(&[1, 2, 3]);
+    assert_eq!(set, expected);
 }
 
 #[test]
 #[ignore]
-fn intersecting_empty_sets_return_empty_set() {
-    let set1: CustomSet<()> = CustomSet::new(&[]);
-    let set2: CustomSet<()> = CustomSet::new(&[]);
-    assert_eq!(set1.intersection(&set2), CustomSet::new(&[]));
+fn intersection_of_two_empty_sets_is_an_empty_set() {
+    let set_1 = CustomSet::<i32>::new(&[]);
+    let set_2 = CustomSet::<i32>::new(&[]);
+    let expected = CustomSet::<i32>::new(&[]);
+    assert_eq!(set_1.intersection(&set_2), expected);
 }
 
 #[test]
 #[ignore]
-fn intersecting_empty_set_with_non_empty_returns_empty_set() {
-    let set1 = CustomSet::new(&[]);
-    let set2 = CustomSet::new(&[3, 2, 5]);
-    assert_eq!(set1.intersection(&set2), CustomSet::new(&[]));
+fn intersection_of_an_empty_set_and_non_empty_set_is_an_empty_set() {
+    let set_1 = CustomSet::<i32>::new(&[]);
+    let set_2 = CustomSet::<i32>::new(&[3, 2, 5]);
+    let expected = CustomSet::<i32>::new(&[]);
+    assert_eq!(set_1.intersection(&set_2), expected);
 }
 
 #[test]
 #[ignore]
-fn intersecting_non_empty_set_with_empty_returns_empty_set() {
-    let set1 = CustomSet::new(&[1, 2, 3, 4]);
-    let set2 = CustomSet::new(&[]);
-    assert_eq!(set1.intersection(&set2), CustomSet::new(&[]));
+fn intersection_of_a_non_empty_set_and_an_empty_set_is_an_empty_set() {
+    let set_1 = CustomSet::<i32>::new(&[1, 2, 3, 4]);
+    let set_2 = CustomSet::<i32>::new(&[]);
+    let expected = CustomSet::<i32>::new(&[]);
+    assert_eq!(set_1.intersection(&set_2), expected);
 }
 
 #[test]
 #[ignore]
 fn intersection_of_two_sets_with_no_shared_elements_is_an_empty_set() {
-    let set1 = CustomSet::new(&[1, 2, 3]);
-    let set2 = CustomSet::new(&[4, 5, 6]);
-    assert_eq!(set1.intersection(&set2), CustomSet::new(&[]));
-    assert_eq!(set2.intersection(&set1), CustomSet::new(&[]));
+    let set_1 = CustomSet::<i32>::new(&[1, 2, 3]);
+    let set_2 = CustomSet::<i32>::new(&[4, 5, 6]);
+    let expected = CustomSet::<i32>::new(&[]);
+    assert_eq!(set_1.intersection(&set_2), expected);
 }
 
 #[test]
 #[ignore]
 fn intersection_of_two_sets_with_shared_elements_is_a_set_of_the_shared_elements() {
-    let set1 = CustomSet::new(&[1, 2, 3, 4]);
-    let set2 = CustomSet::new(&[3, 2, 5]);
-    assert_eq!(set1.intersection(&set2), CustomSet::new(&[2, 3]));
-    assert_eq!(set2.intersection(&set1), CustomSet::new(&[2, 3]));
+    let set_1 = CustomSet::<i32>::new(&[1, 2, 3, 4]);
+    let set_2 = CustomSet::<i32>::new(&[3, 2, 5]);
+    let expected = CustomSet::<i32>::new(&[2, 3]);
+    assert_eq!(set_1.intersection(&set_2), expected);
 }
 
 #[test]
 #[ignore]
-fn difference_of_two_empty_sets_is_empty_set() {
-    let set1: CustomSet<()> = CustomSet::new(&[]);
-    let set2: CustomSet<()> = CustomSet::new(&[]);
-    assert_eq!(set1.difference(&set2), CustomSet::new(&[]));
+fn difference_of_two_empty_sets_is_an_empty_set() {
+    let set_1 = CustomSet::<i32>::new(&[]);
+    let set_2 = CustomSet::<i32>::new(&[]);
+    let expected = CustomSet::<i32>::new(&[]);
+    assert_eq!(set_1.difference(&set_2), expected);
 }
 
 #[test]
 #[ignore]
-fn difference_of_an_empty_and_non_empty_set_is_an_empty_set() {
-    let set1 = CustomSet::new(&[]);
-    let set2 = CustomSet::new(&[3, 2, 5]);
-    assert_eq!(set1.difference(&set2), CustomSet::new(&[]));
+fn difference_of_empty_set_and_non_empty_set_is_an_empty_set() {
+    let set_1 = CustomSet::<i32>::new(&[]);
+    let set_2 = CustomSet::<i32>::new(&[3, 2, 5]);
+    let expected = CustomSet::<i32>::new(&[]);
+    assert_eq!(set_1.difference(&set_2), expected);
 }
 
 #[test]
 #[ignore]
-fn difference_of_a_non_empty_set_and_empty_set_is_the_non_empty_set() {
-    let set1 = CustomSet::new(&[1, 2, 3, 4]);
-    let set2 = CustomSet::new(&[]);
-    assert_eq!(set1.difference(&set2), CustomSet::new(&[1, 2, 3, 4]));
+fn difference_of_a_non_empty_set_and_an_empty_set_is_the_non_empty_set() {
+    let set_1 = CustomSet::<i32>::new(&[1, 2, 3, 4]);
+    let set_2 = CustomSet::<i32>::new(&[]);
+    let expected = CustomSet::<i32>::new(&[1, 2, 3, 4]);
+    assert_eq!(set_1.difference(&set_2), expected);
 }
 
 #[test]
 #[ignore]
-fn difference_of_two_non_empty_sets_is_elements_only_in_first_set_one() {
-    let set1 = CustomSet::new(&[3, 2, 1]);
-    let set2 = CustomSet::new(&[2, 4]);
-    assert_eq!(set1.difference(&set2), CustomSet::new(&[1, 3]));
+fn difference_of_two_non_empty_sets_is_a_set_of_elements_that_are_only_in_the_first_set() {
+    let set_1 = CustomSet::<i32>::new(&[3, 2, 1]);
+    let set_2 = CustomSet::<i32>::new(&[2, 4]);
+    let expected = CustomSet::<i32>::new(&[1, 3]);
+    assert_eq!(set_1.difference(&set_2), expected);
 }
 
 #[test]
 #[ignore]
-fn union_of_two_empty_sets_is_empty_set() {
-    let set1: CustomSet<()> = CustomSet::new(&[]);
-    let set2: CustomSet<()> = CustomSet::new(&[]);
-    assert_eq!(set1.union(&set2), CustomSet::new(&[]));
+fn union_of_empty_sets_is_an_empty_set() {
+    let set_1 = CustomSet::<i32>::new(&[]);
+    let set_2 = CustomSet::<i32>::new(&[]);
+    let expected = CustomSet::<i32>::new(&[]);
+    assert_eq!(set_1.union(&set_2), expected);
 }
 
 #[test]
 #[ignore]
-fn union_of_empty_set_and_non_empty_set_is_all_elements() {
-    let set1 = CustomSet::new(&[]);
-    let set2 = CustomSet::new(&[2]);
-    assert_eq!(set1.union(&set2), CustomSet::new(&[2]));
+fn union_of_an_empty_set_and_non_empty_set_is_the_non_empty_set() {
+    let set_1 = CustomSet::<i32>::new(&[]);
+    let set_2 = CustomSet::<i32>::new(&[2]);
+    let expected = CustomSet::<i32>::new(&[2]);
+    assert_eq!(set_1.union(&set_2), expected);
 }
 
 #[test]
 #[ignore]
-fn union_of_non_empty_set_and_empty_set_is_the_non_empty_set() {
-    let set1 = CustomSet::new(&[1, 3]);
-    let set2 = CustomSet::new(&[]);
-    assert_eq!(set1.union(&set2), CustomSet::new(&[1, 3]));
+fn union_of_a_non_empty_set_and_empty_set_is_the_non_empty_set() {
+    let set_1 = CustomSet::<i32>::new(&[1, 3]);
+    let set_2 = CustomSet::<i32>::new(&[]);
+    let expected = CustomSet::<i32>::new(&[1, 3]);
+    assert_eq!(set_1.union(&set_2), expected);
 }
 
 #[test]
 #[ignore]
 fn union_of_non_empty_sets_contains_all_unique_elements() {
-    let set1 = CustomSet::new(&[1, 3]);
-    let set2 = CustomSet::new(&[2, 3]);
-    assert_eq!(set1.union(&set2), CustomSet::new(&[3, 2, 1]));
+    let set_1 = CustomSet::<i32>::new(&[1, 3]);
+    let set_2 = CustomSet::<i32>::new(&[2, 3]);
+    let expected = CustomSet::<i32>::new(&[3, 2, 1]);
+    assert_eq!(set_1.union(&set_2), expected);
 }
diff --git a/problem-specifications b/problem-specifications
index 03220a9ce..988eafc34 160000
--- a/problem-specifications
+++ b/problem-specifications
@@ -1 +1 @@
-Subproject commit 03220a9ceb507f46cb70e317aaf1620237435144
+Subproject commit 988eafc342c42defd78d1fc87b80d8586bc01ac4