diff --git a/src/prolog/builtins/terms.kt b/src/prolog/logic/terms.kt
similarity index 100%
rename from src/prolog/builtins/terms.kt
rename to src/prolog/logic/terms.kt
diff --git a/tests/lexer/LexerScanPrologTest.kt b/tests/lexer/ScanPrologTests.kt
similarity index 98%
rename from tests/lexer/LexerScanPrologTest.kt
rename to tests/lexer/ScanPrologTests.kt
index 7d25492..4f39a60 100644
--- a/tests/lexer/LexerScanPrologTest.kt
+++ b/tests/lexer/ScanPrologTests.kt
@@ -9,7 +9,7 @@ import kotlin.test.assertEquals
  *
  * These tests are based on the Prolog syntax.
  */
-class LexerScanPrologTest {
+class ScanPrologTests {
     @Test
     fun scan_simple_atom() {
         val tokens = Lexer("atom.").scan()
diff --git a/tests/lexer/LexerScanTest.kt b/tests/lexer/ScanTests.kt
similarity index 99%
rename from tests/lexer/LexerScanTest.kt
rename to tests/lexer/ScanTests.kt
index bd4d515..808ef1a 100644
--- a/tests/lexer/LexerScanTest.kt
+++ b/tests/lexer/ScanTests.kt
@@ -4,7 +4,7 @@ import org.junit.jupiter.api.Test
 import org.junit.jupiter.api.assertThrows
 import org.junit.jupiter.api.Assertions.*
 
-class LexerScanTest {
+class ScanTests {
     @Test
     fun scan_emptyString_returns_EOF() {
         val tokens = Lexer("").scan()
diff --git a/tests/prolog/EvaluationTest.kt b/tests/prolog/EvaluationTests.kt
similarity index 99%
rename from tests/prolog/EvaluationTest.kt
rename to tests/prolog/EvaluationTests.kt
index de58432..6fd5fe5 100644
--- a/tests/prolog/EvaluationTest.kt
+++ b/tests/prolog/EvaluationTests.kt
@@ -13,7 +13,7 @@ import prolog.ast.terms.Atom
 import prolog.ast.terms.Structure
 import prolog.ast.terms.Variable
 
-class EvaluationTest {
+class EvaluationTests {
     @BeforeEach
     fun setUp() {
         Program.clear()
diff --git a/tests/prolog/builtins/TermAnalysisConstructionTest.kt b/tests/prolog/builtins/TermAnalysisConstructionTest.kt
index 09c5a0a..a137fca 100644
--- a/tests/prolog/builtins/TermAnalysisConstructionTest.kt
+++ b/tests/prolog/builtins/TermAnalysisConstructionTest.kt
@@ -7,6 +7,7 @@ import prolog.ast.terms.Atom
 import prolog.ast.terms.Structure
 import prolog.logic.atomic
 import prolog.logic.compound
+import prolog.logic.functor
 
 /**
  * Based on [Predicates for analyzing/constructing terms](https://github.com/dtonhofer/prolog_notes/blob/master/swipl_notes/about_term_analysis_and_construction/term_analysis_construction.png)
diff --git a/tests/prolog/builtins/UnificationTest.kt b/tests/prolog/builtins/UnificationOperatorsTests.kt
similarity index 97%
rename from tests/prolog/builtins/UnificationTest.kt
rename to tests/prolog/builtins/UnificationOperatorsTests.kt
index 6ca212a..73dcfc7 100644
--- a/tests/prolog/builtins/UnificationTest.kt
+++ b/tests/prolog/builtins/UnificationOperatorsTests.kt
@@ -6,7 +6,7 @@ import prolog.ast.terms.Atom
 import prolog.ast.arithmetic.Integer
 import prolog.ast.terms.Variable
 
-class UnificationTest {
+class UnificationOperatorsTests {
     /**
      * ?- X == a.
      * false.
diff --git a/tests/prolog/logic/UnifyTest.kt b/tests/prolog/logic/UnifyTests.kt
similarity index 99%
rename from tests/prolog/logic/UnifyTest.kt
rename to tests/prolog/logic/UnifyTests.kt
index c306081..f2b3c57 100644
--- a/tests/prolog/logic/UnifyTest.kt
+++ b/tests/prolog/logic/UnifyTests.kt
@@ -13,7 +13,7 @@ import prolog.builtins.Add
 /*
  * Based on: https://en.wikipedia.org/wiki/Unification_%28computer_science%29#Examples_of_syntactic_unification_of_first-order_terms
  */
-class UnifyTest {
+class UnifyTests {
     @Test
     fun identical_atoms_unify() {
         val atom1 = Atom("a")
diff --git a/tests/prolog/builtins/VerificationTest.kt b/tests/prolog/logic/VerificationTests.kt
similarity index 97%
rename from tests/prolog/builtins/VerificationTest.kt
rename to tests/prolog/logic/VerificationTests.kt
index 632808d..7631003 100644
--- a/tests/prolog/builtins/VerificationTest.kt
+++ b/tests/prolog/logic/VerificationTests.kt
@@ -1,4 +1,4 @@
-package prolog.builtins
+package prolog.logic
 
 import org.junit.jupiter.api.Assertions.assertFalse
 import org.junit.jupiter.api.Assertions.assertTrue
@@ -7,11 +7,8 @@ import prolog.Substitutions
 import prolog.ast.terms.Atom
 import prolog.ast.terms.Structure
 import prolog.ast.terms.Variable
-import prolog.logic.compound
-import prolog.logic.nonvariable
-import prolog.logic.variable
 
-class VerificationTest {
+class VerificationTests {
     @Test
     fun unbound_variable_is_var() {
         val variable = Variable("X")