diff --git a/nemo-python/tests/test_blackbox.py b/nemo-python/tests/test_blackbox.py
index e2d6a453f..8da51750b 100644
--- a/nemo-python/tests/test_blackbox.py
+++ b/nemo-python/tests/test_blackbox.py
@@ -3,7 +3,7 @@
 import csv
 import os
 import math
-from os.path import dirname, exists, abspath, isfile
+from os.path import dirname, exists, abspath, isfile, isdir
 
 from nmo_python import load_file, NemoEngine, NemoOutputManager
 
@@ -18,82 +18,80 @@ def stringify(value):
     return str(value)
 
 
-def generate_test(file):
+def run_blackbox_test(self, file):
+    os.chdir(self.path)
+
+    program = load_file(file)
     program_name = file.removesuffix(".rls")
-    test_name = "test_" + program_name
+    engine = NemoEngine(program)
+    engine.reason()
+
+    for relation in program.output_predicates():
+        expected_results_file_name = os.path.join(program_name, f"{relation}.csv")
 
-    def run_test(self):
-        os.chdir(self.path)
+        if not exists(expected_results_file_name):
+            continue
 
-        program = load_file(file)
-        engine = NemoEngine(program)
-        engine.reason()
+        with tempfile.TemporaryDirectory() as tmp_dir:
+            output_manager = NemoOutputManager(tmp_dir)
+            engine.write_result(f"{relation}", output_manager)
 
-        for relation in program.output_predicates():
-            expected_results_file_name = os.path.join(
-                program_name, f"{relation}.csv"
-            )
+            with open(os.path.join(tmp_dir, f"{relation}.csv")) as results_file:
+                results = list(csv.reader(results_file))
 
-            if not exists(expected_results_file_name):
-                continue
+            with open(expected_results_file_name) as expected_results_file:
+                expected = list(csv.reader(expected_results_file))
 
-            with tempfile.TemporaryDirectory() as tmp_dir:
-                output_manager = NemoOutputManager(tmp_dir)
-                engine.write_result(f"{relation}", output_manager)
+            for result in results:
+                self.assertTrue(
+                    result in expected,
+                    f"unexpected {result} in {relation}",
+                )
 
-                with open(
-                    os.path.join(tmp_dir, f"{relation}.csv")
-                ) as results_file:
-                    results = list(csv.reader(results_file))
+                expected.remove(result)
+
+            self.assertTrue(
+                len(expected) == 0,
+                f"missing results in {relation}: {expected}",
+            )
 
-                    with open(
-                        expected_results_file_name
-                    ) as expected_results_file:
-                        expected = list(csv.reader(expected_results_file))
 
-                        for result in results:
-                            self.assertTrue(
-                                result in expected,
-                                f"unexpected {result} in {relation}",
-                            )
+def generate_test(file):
+    program_name = file.removesuffix(".rls")
+    test_name = "test_" + program_name
 
-                            expected.remove(result)
+    return test_name, classmethod(lambda self: run_blackbox_test(self, file))
 
-                        self.assertTrue(
-                            len(expected) == 0,
-                            f"missing results in {relation}: {expected}",
-                        )
 
-    return test_name, classmethod(run_test)
+def visit_path(test_path, loader, tests, subgroup_path=[]):
+    os.chdir(test_path)
+    dir_entries = os.listdir(test_path)
+    subgroup_path.append(os.path.basename(test_path))
 
+    for subdir in filter(isdir, dir_entries):
+        visit_path(os.path.join(test_path, subdir), loader, tests, subgroup_path)
+        os.chdir(test_path)
 
-def end_to_end_test_case(test_path):
-    class_name = os.path.basename(test_path)
-    test_case = type(class_name, (unittest.TestCase,), {"path": test_path})
+    rules_files = list(filter(lambda f: isfile(f) and f.endswith(".rls"), dir_entries))
 
-    for file in os.listdir(test_path):
-        if not isfile(os.path.join(test_path, file)):
-            continue
+    if rules_files.count == 0:
+        return
 
-        if not file.endswith(".rls"):
-            continue
+    class_name = "_".join(subgroup_path)
+    test_case = type(class_name, (unittest.TestCase,), {"path": test_path})
 
+    for file in rules_files:
         name, method = generate_test(file)
         setattr(test_case, name, method)
 
-    return test_case
+    tests.addTests(loader.loadTestsFromTestCase(test_case))
+    subgroup_path.pop()
 
 
 def load_tests(loader, tests, pattern):
-    test_cases_dir = os.path.join(
-        dirname(__file__), "..", "..", "resources", "testcases"
-    )
-
-    for directory in os.listdir(test_cases_dir):
-        path = abspath(os.path.join(test_cases_dir, directory))
-        test_case = end_to_end_test_case(path)
-        tests.addTests(loader.loadTestsFromTestCase(test_case))
+    test_cases_dir = os.path.join(dirname(__file__), "..", "..", "resources", "testcases")
 
+    visit_path(abspath(test_cases_dir), loader, tests)
     return tests
 
 
diff --git a/resources/testcases/aggregate_basic/anyCount.rls b/resources/testcases/aggregate/anyCount.rls
similarity index 100%
rename from resources/testcases/aggregate_basic/anyCount.rls
rename to resources/testcases/aggregate/anyCount.rls
diff --git a/resources/testcases/aggregate_basic/anyCount/r0.csv b/resources/testcases/aggregate/anyCount/r0.csv
similarity index 100%
rename from resources/testcases/aggregate_basic/anyCount/r0.csv
rename to resources/testcases/aggregate/anyCount/r0.csv
diff --git a/resources/testcases/aggregate_basic/firstVariable.rls b/resources/testcases/aggregate/firstVariable.rls
similarity index 100%
rename from resources/testcases/aggregate_basic/firstVariable.rls
rename to resources/testcases/aggregate/firstVariable.rls
diff --git a/resources/testcases/aggregate_basic/firstVariable/r0.csv b/resources/testcases/aggregate/firstVariable/r0.csv
similarity index 100%
rename from resources/testcases/aggregate_basic/firstVariable/r0.csv
rename to resources/testcases/aggregate/firstVariable/r0.csv
diff --git a/resources/testcases/aggregate_basic/firstVariable/r1.csv b/resources/testcases/aggregate/firstVariable/r1.csv
similarity index 100%
rename from resources/testcases/aggregate_basic/firstVariable/r1.csv
rename to resources/testcases/aggregate/firstVariable/r1.csv
diff --git a/resources/testcases/aggregate_basic/firstVariable/r2.csv b/resources/testcases/aggregate/firstVariable/r2.csv
similarity index 100%
rename from resources/testcases/aggregate_basic/firstVariable/r2.csv
rename to resources/testcases/aggregate/firstVariable/r2.csv
diff --git a/resources/testcases/aggregate_basic/firstVariable/r3.csv b/resources/testcases/aggregate/firstVariable/r3.csv
similarity index 100%
rename from resources/testcases/aggregate_basic/firstVariable/r3.csv
rename to resources/testcases/aggregate/firstVariable/r3.csv
diff --git a/resources/testcases/aggregate_basic/groupBy.rls b/resources/testcases/aggregate/groupBy.rls
similarity index 100%
rename from resources/testcases/aggregate_basic/groupBy.rls
rename to resources/testcases/aggregate/groupBy.rls
diff --git a/resources/testcases/aggregate_basic/groupBy/r0.csv b/resources/testcases/aggregate/groupBy/r0.csv
similarity index 100%
rename from resources/testcases/aggregate_basic/groupBy/r0.csv
rename to resources/testcases/aggregate/groupBy/r0.csv
diff --git a/resources/testcases/aggregate_basic/groupBy/r1.csv b/resources/testcases/aggregate/groupBy/r1.csv
similarity index 100%
rename from resources/testcases/aggregate_basic/groupBy/r1.csv
rename to resources/testcases/aggregate/groupBy/r1.csv
diff --git a/resources/testcases/aggregate_basic/groupBy/r2.csv b/resources/testcases/aggregate/groupBy/r2.csv
similarity index 100%
rename from resources/testcases/aggregate_basic/groupBy/r2.csv
rename to resources/testcases/aggregate/groupBy/r2.csv
diff --git a/resources/testcases/aggregate_basic/groupBy/r3.csv b/resources/testcases/aggregate/groupBy/r3.csv
similarity index 100%
rename from resources/testcases/aggregate_basic/groupBy/r3.csv
rename to resources/testcases/aggregate/groupBy/r3.csv
diff --git a/resources/testcases/aggregate_basic/groupByIdempotent.rls b/resources/testcases/aggregate/groupByIdempotent.rls
similarity index 100%
rename from resources/testcases/aggregate_basic/groupByIdempotent.rls
rename to resources/testcases/aggregate/groupByIdempotent.rls
diff --git a/resources/testcases/aggregate_basic/groupByIdempotent/r0.csv b/resources/testcases/aggregate/groupByIdempotent/r0.csv
similarity index 100%
rename from resources/testcases/aggregate_basic/groupByIdempotent/r0.csv
rename to resources/testcases/aggregate/groupByIdempotent/r0.csv
diff --git a/resources/testcases/aggregate_basic/groupByIdempotent/r1.csv b/resources/testcases/aggregate/groupByIdempotent/r1.csv
similarity index 100%
rename from resources/testcases/aggregate_basic/groupByIdempotent/r1.csv
rename to resources/testcases/aggregate/groupByIdempotent/r1.csv
diff --git a/resources/testcases/aggregate_basic/lastVariable.rls b/resources/testcases/aggregate/lastVariable.rls
similarity index 100%
rename from resources/testcases/aggregate_basic/lastVariable.rls
rename to resources/testcases/aggregate/lastVariable.rls
diff --git a/resources/testcases/aggregate_basic/lastVariable/r0.csv b/resources/testcases/aggregate/lastVariable/r0.csv
similarity index 100%
rename from resources/testcases/aggregate_basic/lastVariable/r0.csv
rename to resources/testcases/aggregate/lastVariable/r0.csv
diff --git a/resources/testcases/aggregate_basic/lastVariable/r1.csv b/resources/testcases/aggregate/lastVariable/r1.csv
similarity index 100%
rename from resources/testcases/aggregate_basic/lastVariable/r1.csv
rename to resources/testcases/aggregate/lastVariable/r1.csv
diff --git a/resources/testcases/aggregate_basic/sources/dataA.csv b/resources/testcases/aggregate/sources/dataA.csv
similarity index 100%
rename from resources/testcases/aggregate_basic/sources/dataA.csv
rename to resources/testcases/aggregate/sources/dataA.csv
diff --git a/resources/testcases/aggregate_basic/stratification.rls b/resources/testcases/aggregate/stratification.rls
similarity index 100%
rename from resources/testcases/aggregate_basic/stratification.rls
rename to resources/testcases/aggregate/stratification.rls
diff --git a/resources/testcases/aggregate_basic/stratification/r1.csv b/resources/testcases/aggregate/stratification/r1.csv
similarity index 100%
rename from resources/testcases/aggregate_basic/stratification/r1.csv
rename to resources/testcases/aggregate/stratification/r1.csv
diff --git a/resources/testcases/aggregate_basic/stratification/r2.csv b/resources/testcases/aggregate/stratification/r2.csv
similarity index 100%
rename from resources/testcases/aggregate_basic/stratification/r2.csv
rename to resources/testcases/aggregate/stratification/r2.csv
diff --git a/resources/testcases/aggregate_basic/stratification/r3.csv b/resources/testcases/aggregate/stratification/r3.csv
similarity index 100%
rename from resources/testcases/aggregate_basic/stratification/r3.csv
rename to resources/testcases/aggregate/stratification/r3.csv
diff --git a/resources/testcases/comparison/run.rls b/resources/testcases/arithmetic/comparison.rls
similarity index 100%
rename from resources/testcases/comparison/run.rls
rename to resources/testcases/arithmetic/comparison.rls
diff --git a/resources/testcases/comparison/run/complex.csv b/resources/testcases/arithmetic/comparison/complex.csv
similarity index 100%
rename from resources/testcases/comparison/run/complex.csv
rename to resources/testcases/arithmetic/comparison/complex.csv
diff --git a/resources/testcases/comparison/run/x_greater_than_five.csv b/resources/testcases/arithmetic/comparison/x_greater_than_five.csv
similarity index 100%
rename from resources/testcases/comparison/run/x_greater_than_five.csv
rename to resources/testcases/arithmetic/comparison/x_greater_than_five.csv
diff --git a/resources/testcases/comparison/run/x_less_than_three.csv b/resources/testcases/arithmetic/comparison/x_less_than_three.csv
similarity index 100%
rename from resources/testcases/comparison/run/x_less_than_three.csv
rename to resources/testcases/arithmetic/comparison/x_less_than_three.csv
diff --git a/resources/testcases/comparison/run/x_unequals_three.csv b/resources/testcases/arithmetic/comparison/x_unequals_three.csv
similarity index 100%
rename from resources/testcases/comparison/run/x_unequals_three.csv
rename to resources/testcases/arithmetic/comparison/x_unequals_three.csv
diff --git a/resources/testcases/comparison/run/y_equals_nine.csv b/resources/testcases/arithmetic/comparison/y_equals_nine.csv
similarity index 100%
rename from resources/testcases/comparison/run/y_equals_nine.csv
rename to resources/testcases/arithmetic/comparison/y_equals_nine.csv
diff --git a/resources/testcases/comparison/run/y_greater_than_eq_seven.csv b/resources/testcases/arithmetic/comparison/y_greater_than_eq_seven.csv
similarity index 100%
rename from resources/testcases/comparison/run/y_greater_than_eq_seven.csv
rename to resources/testcases/arithmetic/comparison/y_greater_than_eq_seven.csv
diff --git a/resources/testcases/comparison/run/y_less_than_eq_five.csv b/resources/testcases/arithmetic/comparison/y_less_than_eq_five.csv
similarity index 100%
rename from resources/testcases/comparison/run/y_less_than_eq_five.csv
rename to resources/testcases/arithmetic/comparison/y_less_than_eq_five.csv
diff --git a/resources/testcases/comparison/run/y_unequals_five.csv b/resources/testcases/arithmetic/comparison/y_unequals_five.csv
similarity index 100%
rename from resources/testcases/comparison/run/y_unequals_five.csv
rename to resources/testcases/arithmetic/comparison/y_unequals_five.csv
diff --git a/resources/testcases/comparison/sources/data.csv b/resources/testcases/arithmetic/sources/data.csv
similarity index 100%
rename from resources/testcases/comparison/sources/data.csv
rename to resources/testcases/arithmetic/sources/data.csv
diff --git a/resources/testcases/basic/README.md b/resources/testcases/basic/README.md
new file mode 100644
index 000000000..8af7e2719
--- /dev/null
+++ b/resources/testcases/basic/README.md
@@ -0,0 +1,8 @@
+= testcases/basic
+
+Tests / documents all basic functionalities of the rule syntax:
+- join
+- negation
+- projection
+- union
+- assignment
diff --git a/resources/testcases/assignment/run.rls b/resources/testcases/basic/assignment.rls
similarity index 100%
rename from resources/testcases/assignment/run.rls
rename to resources/testcases/basic/assignment.rls
diff --git a/resources/testcases/assignment/run/r.csv b/resources/testcases/basic/assignment/r.csv
similarity index 100%
rename from resources/testcases/assignment/run/r.csv
rename to resources/testcases/basic/assignment/r.csv
diff --git a/resources/testcases/basic_join/run.rls b/resources/testcases/basic/join.rls
similarity index 94%
rename from resources/testcases/basic_join/run.rls
rename to resources/testcases/basic/join.rls
index b75b48410..4bc4d3504 100644
--- a/resources/testcases/basic_join/run.rls
+++ b/resources/testcases/basic/join.rls
@@ -4,4 +4,4 @@
 
 J1(?X, ?Y, ?Z) :- sourceA(?X, ?Z, ?Y), sourceB(?X, ?Y, ?T) .
 J2(?X, ?Y, ?Z) :- sourceA(?Z, ?Y, ?X), sourceC(?X, ?Y, ?T) .
-J3(?X, ?Y, ?W) :- sourceA(?T, ?Y, ?X), sourceB(?T, ?Y, ?X), sourceC(?X, ?Y, ?W) .
\ No newline at end of file
+J3(?X, ?Y, ?W) :- sourceA(?T, ?Y, ?X), sourceB(?T, ?Y, ?X), sourceC(?X, ?Y, ?W) .
diff --git a/resources/testcases/basic_join/run/J1.csv b/resources/testcases/basic/join/J1.csv
similarity index 100%
rename from resources/testcases/basic_join/run/J1.csv
rename to resources/testcases/basic/join/J1.csv
diff --git a/resources/testcases/basic_join/output/J2.csv b/resources/testcases/basic/join/J2.csv
similarity index 100%
rename from resources/testcases/basic_join/output/J2.csv
rename to resources/testcases/basic/join/J2.csv
diff --git a/resources/testcases/basic_join/output/J3.csv b/resources/testcases/basic/join/J3.csv
similarity index 100%
rename from resources/testcases/basic_join/output/J3.csv
rename to resources/testcases/basic/join/J3.csv
diff --git a/resources/testcases/basic_negation/run.rls b/resources/testcases/basic/negation.rls
similarity index 100%
rename from resources/testcases/basic_negation/run.rls
rename to resources/testcases/basic/negation.rls
diff --git a/resources/testcases/basic_negation/run/filteredX.csv b/resources/testcases/basic/negation/filteredX.csv
similarity index 100%
rename from resources/testcases/basic_negation/run/filteredX.csv
rename to resources/testcases/basic/negation/filteredX.csv
diff --git a/resources/testcases/basic_negation/run/filteredY.csv b/resources/testcases/basic/negation/filteredY.csv
similarity index 100%
rename from resources/testcases/basic_negation/run/filteredY.csv
rename to resources/testcases/basic/negation/filteredY.csv
diff --git a/resources/testcases/basic_negation/run/filteredZ.csv b/resources/testcases/basic/negation/filteredZ.csv
similarity index 100%
rename from resources/testcases/basic_negation/run/filteredZ.csv
rename to resources/testcases/basic/negation/filteredZ.csv
diff --git a/resources/testcases/basic_negation/run/multiple.csv b/resources/testcases/basic/negation/multiple.csv
similarity index 100%
rename from resources/testcases/basic_negation/run/multiple.csv
rename to resources/testcases/basic/negation/multiple.csv
diff --git a/resources/testcases/basic_negation/run/projectedX.csv b/resources/testcases/basic/negation/projectedX.csv
similarity index 100%
rename from resources/testcases/basic_negation/run/projectedX.csv
rename to resources/testcases/basic/negation/projectedX.csv
diff --git a/resources/testcases/basic_negation/run/projectedXY.csv b/resources/testcases/basic/negation/projectedXY.csv
similarity index 100%
rename from resources/testcases/basic_negation/run/projectedXY.csv
rename to resources/testcases/basic/negation/projectedXY.csv
diff --git a/resources/testcases/basic_negation/run/projectedXZ.csv b/resources/testcases/basic/negation/projectedXZ.csv
similarity index 100%
rename from resources/testcases/basic_negation/run/projectedXZ.csv
rename to resources/testcases/basic/negation/projectedXZ.csv
diff --git a/resources/testcases/basic_negation/run/projectedY.csv b/resources/testcases/basic/negation/projectedY.csv
similarity index 100%
rename from resources/testcases/basic_negation/run/projectedY.csv
rename to resources/testcases/basic/negation/projectedY.csv
diff --git a/resources/testcases/basic_negation/run/projectedYZ.csv b/resources/testcases/basic/negation/projectedYZ.csv
similarity index 100%
rename from resources/testcases/basic_negation/run/projectedYZ.csv
rename to resources/testcases/basic/negation/projectedYZ.csv
diff --git a/resources/testcases/basic_negation/run/projectedZ.csv b/resources/testcases/basic/negation/projectedZ.csv
similarity index 100%
rename from resources/testcases/basic_negation/run/projectedZ.csv
rename to resources/testcases/basic/negation/projectedZ.csv
diff --git a/resources/testcases/basic_negation/run/reordered.csv b/resources/testcases/basic/negation/reordered.csv
similarity index 100%
rename from resources/testcases/basic_negation/run/reordered.csv
rename to resources/testcases/basic/negation/reordered.csv
diff --git a/resources/testcases/basic_negation/run/singlePositionX.csv b/resources/testcases/basic/negation/singlePositionX.csv
similarity index 100%
rename from resources/testcases/basic_negation/run/singlePositionX.csv
rename to resources/testcases/basic/negation/singlePositionX.csv
diff --git a/resources/testcases/basic_negation/run/singlePositionY.csv b/resources/testcases/basic/negation/singlePositionY.csv
similarity index 100%
rename from resources/testcases/basic_negation/run/singlePositionY.csv
rename to resources/testcases/basic/negation/singlePositionY.csv
diff --git a/resources/testcases/basic_negation/run/singlePositionZ.csv b/resources/testcases/basic/negation/singlePositionZ.csv
similarity index 100%
rename from resources/testcases/basic_negation/run/singlePositionZ.csv
rename to resources/testcases/basic/negation/singlePositionZ.csv
diff --git a/resources/testcases/basic_projection/run.rls b/resources/testcases/basic/projection.rls
similarity index 100%
rename from resources/testcases/basic_projection/run.rls
rename to resources/testcases/basic/projection.rls
diff --git a/resources/testcases/basic_projection/run/A.csv b/resources/testcases/basic/projection/A.csv
similarity index 100%
rename from resources/testcases/basic_projection/run/A.csv
rename to resources/testcases/basic/projection/A.csv
diff --git a/resources/testcases/basic_projection/run/B.csv b/resources/testcases/basic/projection/B.csv
similarity index 100%
rename from resources/testcases/basic_projection/run/B.csv
rename to resources/testcases/basic/projection/B.csv
diff --git a/resources/testcases/basic_projection/run/C.csv b/resources/testcases/basic/projection/C.csv
similarity index 100%
rename from resources/testcases/basic_projection/run/C.csv
rename to resources/testcases/basic/projection/C.csv
diff --git a/resources/testcases/basic_projection/run/D.csv b/resources/testcases/basic/projection/D.csv
similarity index 100%
rename from resources/testcases/basic_projection/run/D.csv
rename to resources/testcases/basic/projection/D.csv
diff --git a/resources/testcases/basic_projection/run/E.csv b/resources/testcases/basic/projection/E.csv
similarity index 100%
rename from resources/testcases/basic_projection/run/E.csv
rename to resources/testcases/basic/projection/E.csv
diff --git a/resources/testcases/basic_negation/sources/S1.csv b/resources/testcases/basic/sources/S1.csv
similarity index 100%
rename from resources/testcases/basic_negation/sources/S1.csv
rename to resources/testcases/basic/sources/S1.csv
diff --git a/resources/testcases/basic_negation/sources/S2.csv b/resources/testcases/basic/sources/S2.csv
similarity index 100%
rename from resources/testcases/basic_negation/sources/S2.csv
rename to resources/testcases/basic/sources/S2.csv
diff --git a/resources/testcases/basic_negation/sources/S3.csv b/resources/testcases/basic/sources/S3.csv
similarity index 100%
rename from resources/testcases/basic_negation/sources/S3.csv
rename to resources/testcases/basic/sources/S3.csv
diff --git a/resources/testcases/basic_projection/sources/data.csv b/resources/testcases/basic/sources/data.csv
similarity index 100%
rename from resources/testcases/basic_projection/sources/data.csv
rename to resources/testcases/basic/sources/data.csv
diff --git a/resources/testcases/basic_join/sources/dataA.csv b/resources/testcases/basic/sources/dataA.csv
similarity index 100%
rename from resources/testcases/basic_join/sources/dataA.csv
rename to resources/testcases/basic/sources/dataA.csv
diff --git a/resources/testcases/basic_join/sources/dataB.csv b/resources/testcases/basic/sources/dataB.csv
similarity index 100%
rename from resources/testcases/basic_join/sources/dataB.csv
rename to resources/testcases/basic/sources/dataB.csv
diff --git a/resources/testcases/basic_join/sources/dataC.csv b/resources/testcases/basic/sources/dataC.csv
similarity index 100%
rename from resources/testcases/basic_join/sources/dataC.csv
rename to resources/testcases/basic/sources/dataC.csv
diff --git a/resources/testcases/basic_negation/sources/main.csv b/resources/testcases/basic/sources/main.csv
similarity index 100%
rename from resources/testcases/basic_negation/sources/main.csv
rename to resources/testcases/basic/sources/main.csv
diff --git a/resources/testcases/basic_union/run.rls b/resources/testcases/basic/union.rls
similarity index 100%
rename from resources/testcases/basic_union/run.rls
rename to resources/testcases/basic/union.rls
diff --git a/resources/testcases/basic_union/run/AB.csv b/resources/testcases/basic/union/AB.csv
similarity index 87%
rename from resources/testcases/basic_union/run/AB.csv
rename to resources/testcases/basic/union/AB.csv
index f5684ab51..c94687538 100644
--- a/resources/testcases/basic_union/run/AB.csv
+++ b/resources/testcases/basic/union/AB.csv
@@ -3,5 +3,6 @@ A,C,F
 A,E,F
 A,G,Q
 B,B,D
+B,D,A
 C,D,D
 Q,Q,A
diff --git a/resources/testcases/basic_union/run/ABC.csv b/resources/testcases/basic/union/ABC.csv
similarity index 61%
rename from resources/testcases/basic_union/run/ABC.csv
rename to resources/testcases/basic/union/ABC.csv
index 961513618..aa221b2a4 100644
--- a/resources/testcases/basic_union/run/ABC.csv
+++ b/resources/testcases/basic/union/ABC.csv
@@ -3,6 +3,11 @@ A,C,F
 A,E,F
 A,G,Q
 B,B,D
+B,D,A
 C,D,D
+D,B,Q
+D,B,Z
+D,B,F
+F,E,D
 Q,Q,A
 Z,Z,Z
diff --git a/resources/testcases/basic_join/output.rls b/resources/testcases/basic_join/output.rls
deleted file mode 100644
index 6e4c56ec2..000000000
--- a/resources/testcases/basic_join/output.rls
+++ /dev/null
@@ -1,10 +0,0 @@
-@source sourceA[3]: load-csv("sources/dataA.csv").
-@source sourceB[3]: load-csv("sources/dataB.csv").
-@source sourceC[3]: load-csv("sources/dataC.csv").
-
-J1(?X, ?Y, ?Z) :- sourceA(?X, ?Z, ?Y), sourceB(?X, ?Y, ?T) .
-J2(?X, ?Y, ?Z) :- sourceA(?Z, ?Y, ?X), sourceC(?X, ?Y, ?T) .
-J3(?X, ?Y, ?W) :- sourceA(?T, ?Y, ?X), sourceB(?T, ?Y, ?X), sourceC(?X, ?Y, ?W) .
-
-@output J2 .
-@output J3[3] .
\ No newline at end of file
diff --git a/resources/testcases/basic_join/run/J2.csv b/resources/testcases/basic_join/run/J2.csv
deleted file mode 100644
index 0b7d87f52..000000000
--- a/resources/testcases/basic_join/run/J2.csv
+++ /dev/null
@@ -1,2 +0,0 @@
-D,B,B
-F,E,A
diff --git a/resources/testcases/basic_join/run/J3.csv b/resources/testcases/basic_join/run/J3.csv
deleted file mode 100644
index b3ed53784..000000000
--- a/resources/testcases/basic_join/run/J3.csv
+++ /dev/null
@@ -1,3 +0,0 @@
-D,B,F
-D,B,Q
-D,B,Z
diff --git a/resources/testcases/basic_union/sources/dataB.csv b/resources/testcases/basic_union/sources/dataB.csv
deleted file mode 100644
index a1a5f42ab..000000000
--- a/resources/testcases/basic_union/sources/dataB.csv
+++ /dev/null
@@ -1,5 +0,0 @@
-B,B,D
-A,C,F
-A,G,Q
-Q,Q,A
-C,D,D
\ No newline at end of file
diff --git a/resources/testcases/basic_union/sources/dataC.csv b/resources/testcases/basic_union/sources/dataC.csv
deleted file mode 100644
index ff07c224e..000000000
--- a/resources/testcases/basic_union/sources/dataC.csv
+++ /dev/null
@@ -1,2 +0,0 @@
-Q,Q,A
-Z,Z,Z
\ No newline at end of file
diff --git a/resources/testcases/rdf/ntriples-example2.rls b/resources/testcases/data-formats/rdf/ntriples-example2.rls
similarity index 100%
rename from resources/testcases/rdf/ntriples-example2.rls
rename to resources/testcases/data-formats/rdf/ntriples-example2.rls
diff --git a/resources/testcases/rdf/ntriples-example2/goal.csv b/resources/testcases/data-formats/rdf/ntriples-example2/goal.csv
similarity index 100%
rename from resources/testcases/rdf/ntriples-example2/goal.csv
rename to resources/testcases/data-formats/rdf/ntriples-example2/goal.csv
diff --git a/resources/testcases/rdf/ntriples-example3.rls b/resources/testcases/data-formats/rdf/ntriples-example3.rls
similarity index 100%
rename from resources/testcases/rdf/ntriples-example3.rls
rename to resources/testcases/data-formats/rdf/ntriples-example3.rls
diff --git a/resources/testcases/rdf/ntriples-example3/atoms.csv b/resources/testcases/data-formats/rdf/ntriples-example3/atoms.csv
similarity index 100%
rename from resources/testcases/rdf/ntriples-example3/atoms.csv
rename to resources/testcases/data-formats/rdf/ntriples-example3/atoms.csv
diff --git a/resources/testcases/rdf/ntriples-example3/labels.csv b/resources/testcases/data-formats/rdf/ntriples-example3/labels.csv
similarity index 100%
rename from resources/testcases/rdf/ntriples-example3/labels.csv
rename to resources/testcases/data-formats/rdf/ntriples-example3/labels.csv
diff --git a/resources/testcases/rdf/rdfxml-example7.rls b/resources/testcases/data-formats/rdf/rdfxml-example7.rls
similarity index 100%
rename from resources/testcases/rdf/rdfxml-example7.rls
rename to resources/testcases/data-formats/rdf/rdfxml-example7.rls
diff --git a/resources/testcases/rdf/rdfxml-example7/goal.csv b/resources/testcases/data-formats/rdf/rdfxml-example7/goal.csv
similarity index 100%
rename from resources/testcases/rdf/rdfxml-example7/goal.csv
rename to resources/testcases/data-formats/rdf/rdfxml-example7/goal.csv
diff --git a/resources/testcases/rdf/sources/example2.nt b/resources/testcases/data-formats/rdf/sources/example2.nt
similarity index 100%
rename from resources/testcases/rdf/sources/example2.nt
rename to resources/testcases/data-formats/rdf/sources/example2.nt
diff --git a/resources/testcases/rdf/sources/example2.ttl b/resources/testcases/data-formats/rdf/sources/example2.ttl
similarity index 100%
rename from resources/testcases/rdf/sources/example2.ttl
rename to resources/testcases/data-formats/rdf/sources/example2.ttl
diff --git a/resources/testcases/rdf/sources/example3.nt b/resources/testcases/data-formats/rdf/sources/example3.nt
similarity index 100%
rename from resources/testcases/rdf/sources/example3.nt
rename to resources/testcases/data-formats/rdf/sources/example3.nt
diff --git a/resources/testcases/rdf/sources/example7.rdf b/resources/testcases/data-formats/rdf/sources/example7.rdf
similarity index 100%
rename from resources/testcases/rdf/sources/example7.rdf
rename to resources/testcases/data-formats/rdf/sources/example7.rdf
diff --git a/resources/testcases/rdf/turtle-example2.rls b/resources/testcases/data-formats/rdf/turtle-example2.rls
similarity index 100%
rename from resources/testcases/rdf/turtle-example2.rls
rename to resources/testcases/data-formats/rdf/turtle-example2.rls
diff --git a/resources/testcases/rdf/turtle-example2/goal.csv b/resources/testcases/data-formats/rdf/turtle-example2/goal.csv
similarity index 100%
rename from resources/testcases/rdf/turtle-example2/goal.csv
rename to resources/testcases/data-formats/rdf/turtle-example2/goal.csv
diff --git a/resources/testcases/load_empty/run.rls b/resources/testcases/load_empty/run.rls
deleted file mode 100644
index 2a30fa860..000000000
--- a/resources/testcases/load_empty/run.rls
+++ /dev/null
@@ -1,3 +0,0 @@
-@source source[3]: load-csv("sources/empty.csv").
-
-out(?X, ?Y, ?Z) :- source(?X, ?Y, ?Z) .
\ No newline at end of file
diff --git a/resources/testcases/regression/datalog_constants/regression.yaml b/resources/testcases/regression/datalog_constants/regression.yaml
new file mode 100644
index 000000000..88d5664ef
--- /dev/null
+++ b/resources/testcases/regression/datalog_constants/regression.yaml
@@ -0,0 +1,4 @@
+issue: 392
+title: Panic when filtering for non-existing constant
+tracker: https://github.com/knowsys/nemo/issues/392
+type: bugfix
diff --git a/resources/testcases/datalog_constants/run.rls b/resources/testcases/regression/datalog_constants/run.rls
similarity index 100%
rename from resources/testcases/datalog_constants/run.rls
rename to resources/testcases/regression/datalog_constants/run.rls
diff --git a/resources/testcases/datalog_constants/run/ConstantBodyHead.csv b/resources/testcases/regression/datalog_constants/run/ConstantBodyHead.csv
similarity index 100%
rename from resources/testcases/datalog_constants/run/ConstantBodyHead.csv
rename to resources/testcases/regression/datalog_constants/run/ConstantBodyHead.csv
diff --git a/resources/testcases/datalog_constants/run/ConstantBodyX.csv b/resources/testcases/regression/datalog_constants/run/ConstantBodyX.csv
similarity index 100%
rename from resources/testcases/datalog_constants/run/ConstantBodyX.csv
rename to resources/testcases/regression/datalog_constants/run/ConstantBodyX.csv
diff --git a/resources/testcases/datalog_constants/run/ConstantBodyXY.csv b/resources/testcases/regression/datalog_constants/run/ConstantBodyXY.csv
similarity index 100%
rename from resources/testcases/datalog_constants/run/ConstantBodyXY.csv
rename to resources/testcases/regression/datalog_constants/run/ConstantBodyXY.csv
diff --git a/resources/testcases/datalog_constants/run/ConstantBodyXZ.csv b/resources/testcases/regression/datalog_constants/run/ConstantBodyXZ.csv
similarity index 100%
rename from resources/testcases/datalog_constants/run/ConstantBodyXZ.csv
rename to resources/testcases/regression/datalog_constants/run/ConstantBodyXZ.csv
diff --git a/resources/testcases/datalog_constants/run/ConstantBodyY.csv b/resources/testcases/regression/datalog_constants/run/ConstantBodyY.csv
similarity index 100%
rename from resources/testcases/datalog_constants/run/ConstantBodyY.csv
rename to resources/testcases/regression/datalog_constants/run/ConstantBodyY.csv
diff --git a/resources/testcases/datalog_constants/run/ConstantBodyYZ.csv b/resources/testcases/regression/datalog_constants/run/ConstantBodyYZ.csv
similarity index 100%
rename from resources/testcases/datalog_constants/run/ConstantBodyYZ.csv
rename to resources/testcases/regression/datalog_constants/run/ConstantBodyYZ.csv
diff --git a/resources/testcases/datalog_constants/run/ConstantBodyZ.csv b/resources/testcases/regression/datalog_constants/run/ConstantBodyZ.csv
similarity index 100%
rename from resources/testcases/datalog_constants/run/ConstantBodyZ.csv
rename to resources/testcases/regression/datalog_constants/run/ConstantBodyZ.csv
diff --git a/resources/testcases/datalog_constants/run/ConstantHeadAfter.csv b/resources/testcases/regression/datalog_constants/run/ConstantHeadAfter.csv
similarity index 100%
rename from resources/testcases/datalog_constants/run/ConstantHeadAfter.csv
rename to resources/testcases/regression/datalog_constants/run/ConstantHeadAfter.csv
diff --git a/resources/testcases/datalog_constants/run/ConstantHeadBefore.csv b/resources/testcases/regression/datalog_constants/run/ConstantHeadBefore.csv
similarity index 100%
rename from resources/testcases/datalog_constants/run/ConstantHeadBefore.csv
rename to resources/testcases/regression/datalog_constants/run/ConstantHeadBefore.csv
diff --git a/resources/testcases/datalog_constants/run/ConstantHeadEverywhere.csv b/resources/testcases/regression/datalog_constants/run/ConstantHeadEverywhere.csv
similarity index 100%
rename from resources/testcases/datalog_constants/run/ConstantHeadEverywhere.csv
rename to resources/testcases/regression/datalog_constants/run/ConstantHeadEverywhere.csv
diff --git a/resources/testcases/datalog_constants/run/Exist.csv b/resources/testcases/regression/datalog_constants/run/Exist.csv
similarity index 100%
rename from resources/testcases/datalog_constants/run/Exist.csv
rename to resources/testcases/regression/datalog_constants/run/Exist.csv
diff --git a/resources/testcases/datalog_constants/run/NotExist.csv b/resources/testcases/regression/datalog_constants/run/NotExist.csv
similarity index 100%
rename from resources/testcases/datalog_constants/run/NotExist.csv
rename to resources/testcases/regression/datalog_constants/run/NotExist.csv
diff --git a/resources/testcases/datalog_constants/run/OnlyNewConstants.csv b/resources/testcases/regression/datalog_constants/run/OnlyNewConstants.csv
similarity index 100%
rename from resources/testcases/datalog_constants/run/OnlyNewConstants.csv
rename to resources/testcases/regression/datalog_constants/run/OnlyNewConstants.csv
diff --git a/resources/testcases/datalog_constants/run/OnlyNewConstantsEmpty.csv b/resources/testcases/regression/datalog_constants/run/OnlyNewConstantsEmpty.csv
similarity index 100%
rename from resources/testcases/datalog_constants/run/OnlyNewConstantsEmpty.csv
rename to resources/testcases/regression/datalog_constants/run/OnlyNewConstantsEmpty.csv
diff --git a/resources/testcases/datalog_constants/run/Unknown.csv b/resources/testcases/regression/datalog_constants/run/Unknown.csv
similarity index 100%
rename from resources/testcases/datalog_constants/run/Unknown.csv
rename to resources/testcases/regression/datalog_constants/run/Unknown.csv
diff --git a/resources/testcases/datalog_constants/sources/dataA.csv b/resources/testcases/regression/datalog_constants/sources/dataA.csv
similarity index 100%
rename from resources/testcases/datalog_constants/sources/dataA.csv
rename to resources/testcases/regression/datalog_constants/sources/dataA.csv
diff --git a/resources/testcases/datalog_constants/sources/dataB.csv b/resources/testcases/regression/datalog_constants/sources/dataB.csv
similarity index 100%
rename from resources/testcases/datalog_constants/sources/dataB.csv
rename to resources/testcases/regression/datalog_constants/sources/dataB.csv
diff --git a/resources/testcases/datatype_declarations/run.rls b/resources/testcases/regression/datatypes/declarations/run.rls
similarity index 65%
rename from resources/testcases/datatype_declarations/run.rls
rename to resources/testcases/regression/datatypes/declarations/run.rls
index 596b7f3b4..2741536d5 100644
--- a/resources/testcases/datatype_declarations/run.rls
+++ b/resources/testcases/regression/datatypes/declarations/run.rls
@@ -2,8 +2,8 @@
 @declare c(integer) .
 @declare numeric(integer, float64) .
 
-@source c[1]: load-csv("sources/c.csv") .
-@source numeric[2]: load-csv("sources/numeric.csv") .
+@source c[1]: load-csv("../sources/c.csv") .
+@source numeric[2]: load-csv("../sources/numeric.csv") .
 
 a(Hello, ?X) :- c(?X) .
 b(?Y, ?X) :- a(?X, ?Y) .
diff --git a/resources/testcases/datatype_declarations/run/a.csv b/resources/testcases/regression/datatypes/declarations/run/a.csv
similarity index 100%
rename from resources/testcases/datatype_declarations/run/a.csv
rename to resources/testcases/regression/datatypes/declarations/run/a.csv
diff --git a/resources/testcases/datatype_declarations/run/b.csv b/resources/testcases/regression/datatypes/declarations/run/b.csv
similarity index 100%
rename from resources/testcases/datatype_declarations/run/b.csv
rename to resources/testcases/regression/datatypes/declarations/run/b.csv
diff --git a/resources/testcases/datatype_declarations/run/r.csv b/resources/testcases/regression/datatypes/declarations/run/r.csv
similarity index 100%
rename from resources/testcases/datatype_declarations/run/r.csv
rename to resources/testcases/regression/datatypes/declarations/run/r.csv
diff --git a/resources/testcases/datatype_inference_consistency/no-source.rls b/resources/testcases/regression/datatypes/inference/no-source.rls
similarity index 100%
rename from resources/testcases/datatype_inference_consistency/no-source.rls
rename to resources/testcases/regression/datatypes/inference/no-source.rls
diff --git a/resources/testcases/datatype_inference_consistency/no-source/p.csv b/resources/testcases/regression/datatypes/inference/no-source/p.csv
similarity index 100%
rename from resources/testcases/datatype_inference_consistency/no-source/p.csv
rename to resources/testcases/regression/datatypes/inference/no-source/p.csv
diff --git a/resources/testcases/datatype_inference_consistency/with-source.rls b/resources/testcases/regression/datatypes/inference/with-source.rls
similarity index 60%
rename from resources/testcases/datatype_inference_consistency/with-source.rls
rename to resources/testcases/regression/datatypes/inference/with-source.rls
index a441f0557..37696fb67 100644
--- a/resources/testcases/datatype_inference_consistency/with-source.rls
+++ b/resources/testcases/regression/datatypes/inference/with-source.rls
@@ -1,6 +1,6 @@
 @declare a(integer) .
 
-@source a[1]: load-csv("sources/a.csv") .
+@source a[1]: load-csv("../sources/a.csv") .
 
 c(?X, ?Y) :- b(?X, ?Y) .
 b(?X, ?X) :- a(?X) .
diff --git a/resources/testcases/datatype_inference_consistency/with-source/b.csv b/resources/testcases/regression/datatypes/inference/with-source/b.csv
similarity index 100%
rename from resources/testcases/datatype_inference_consistency/with-source/b.csv
rename to resources/testcases/regression/datatypes/inference/with-source/b.csv
diff --git a/resources/testcases/datatype_inference_consistency/with-source/c.csv b/resources/testcases/regression/datatypes/inference/with-source/c.csv
similarity index 100%
rename from resources/testcases/datatype_inference_consistency/with-source/c.csv
rename to resources/testcases/regression/datatypes/inference/with-source/c.csv
diff --git a/resources/testcases/datatype_normalization/run.rls b/resources/testcases/regression/datatypes/normalization/run.rls
similarity index 90%
rename from resources/testcases/datatype_normalization/run.rls
rename to resources/testcases/regression/datatypes/normalization/run.rls
index 9327764ed..0aa4d05ed 100644
--- a/resources/testcases/datatype_normalization/run.rls
+++ b/resources/testcases/regression/datatypes/normalization/run.rls
@@ -4,7 +4,7 @@
 @declare b(any) .
 @declare c(any) .
 
-@source b[any]: load-csv("sources/b.csv") .
+@source b[any]: load-csv("../sources/b.csv") .
 
 a(Some Constant With Spaces).
 a(<AnotherConstant>).
diff --git a/resources/testcases/datatype_normalization/run/c.csv b/resources/testcases/regression/datatypes/normalization/run/c.csv
similarity index 100%
rename from resources/testcases/datatype_normalization/run/c.csv
rename to resources/testcases/regression/datatypes/normalization/run/c.csv
diff --git a/resources/testcases/datatype_inference_consistency/sources/a.csv b/resources/testcases/regression/datatypes/sources/a.csv
similarity index 100%
rename from resources/testcases/datatype_inference_consistency/sources/a.csv
rename to resources/testcases/regression/datatypes/sources/a.csv
diff --git a/resources/testcases/datatype_normalization/sources/b.csv b/resources/testcases/regression/datatypes/sources/b.csv
similarity index 100%
rename from resources/testcases/datatype_normalization/sources/b.csv
rename to resources/testcases/regression/datatypes/sources/b.csv
diff --git a/resources/testcases/datatype_declarations/sources/c.csv b/resources/testcases/regression/datatypes/sources/c.csv
similarity index 100%
rename from resources/testcases/datatype_declarations/sources/c.csv
rename to resources/testcases/regression/datatypes/sources/c.csv
diff --git a/resources/testcases/datatype_declarations/sources/numeric.csv b/resources/testcases/regression/datatypes/sources/numeric.csv
similarity index 100%
rename from resources/testcases/datatype_declarations/sources/numeric.csv
rename to resources/testcases/regression/datatypes/sources/numeric.csv
diff --git a/resources/testcases/join_by_eq_constraint/integer.rls b/resources/testcases/regression/join_by_eq_constraint/integer.rls
similarity index 100%
rename from resources/testcases/join_by_eq_constraint/integer.rls
rename to resources/testcases/regression/join_by_eq_constraint/integer.rls
diff --git a/resources/testcases/join_by_eq_constraint/integer/intInBody.csv b/resources/testcases/regression/join_by_eq_constraint/integer/intInBody.csv
similarity index 100%
rename from resources/testcases/join_by_eq_constraint/integer/intInBody.csv
rename to resources/testcases/regression/join_by_eq_constraint/integer/intInBody.csv
diff --git a/resources/testcases/regression/join_by_eq_constraint/regression.yaml b/resources/testcases/regression/join_by_eq_constraint/regression.yaml
new file mode 100644
index 000000000..e713f58d5
--- /dev/null
+++ b/resources/testcases/regression/join_by_eq_constraint/regression.yaml
@@ -0,0 +1,4 @@
+issue: 355
+title: Support equality of two integer variables
+tracker: https://github.com/knowsys/nemo/issues/355
+type: bugfix
diff --git a/resources/testcases/join_by_eq_constraint/string.rls b/resources/testcases/regression/join_by_eq_constraint/string.rls
similarity index 100%
rename from resources/testcases/join_by_eq_constraint/string.rls
rename to resources/testcases/regression/join_by_eq_constraint/string.rls
diff --git a/resources/testcases/join_by_eq_constraint/string/literalInBody.csv b/resources/testcases/regression/join_by_eq_constraint/string/literalInBody.csv
similarity index 100%
rename from resources/testcases/join_by_eq_constraint/string/literalInBody.csv
rename to resources/testcases/regression/join_by_eq_constraint/string/literalInBody.csv
diff --git a/resources/testcases/regression/load/empty/regression.yaml b/resources/testcases/regression/load/empty/regression.yaml
new file mode 100644
index 000000000..35ad48856
--- /dev/null
+++ b/resources/testcases/regression/load/empty/regression.yaml
@@ -0,0 +1,4 @@
+issue: 341
+title: invariant violation when reading empty file
+tracker: https://github.com/knowsys/nemo/issues/308
+type: bugfix
diff --git a/resources/testcases/regression/load/empty/run.rls b/resources/testcases/regression/load/empty/run.rls
new file mode 100644
index 000000000..ba8b9b32c
--- /dev/null
+++ b/resources/testcases/regression/load/empty/run.rls
@@ -0,0 +1,3 @@
+@source source[3]: load-csv("../sources/empty.csv").
+
+out(?X, ?Y, ?Z) :- source(?X, ?Y, ?Z) .
\ No newline at end of file
diff --git a/resources/testcases/load_empty/run/out.csv b/resources/testcases/regression/load/empty/run/out.csv
similarity index 100%
rename from resources/testcases/load_empty/run/out.csv
rename to resources/testcases/regression/load/empty/run/out.csv
diff --git a/resources/testcases/load_multiple/run.rls b/resources/testcases/regression/load/multiple/run.rls
similarity index 55%
rename from resources/testcases/load_multiple/run.rls
rename to resources/testcases/regression/load/multiple/run.rls
index 0a459903f..bc2578d73 100644
--- a/resources/testcases/load_multiple/run.rls
+++ b/resources/testcases/regression/load/multiple/run.rls
@@ -1,6 +1,6 @@
-@source source[3]: load-csv("sources/dataA.csv").
-@source source[3]: load-csv("sources/dataB.csv").
-@source source[3]: load-csv("sources/dataC.csv").
+@source source[3]: load-csv("../sources/dataA.csv").
+@source source[3]: load-csv("../sources/dataB.csv").
+@source source[3]: load-csv("../sources/dataC.csv").
 
 source("A", "B", "C") .
 source("B", "C", "D") .
diff --git a/resources/testcases/load_multiple/run/combined.csv b/resources/testcases/regression/load/multiple/run/combined.csv
similarity index 100%
rename from resources/testcases/load_multiple/run/combined.csv
rename to resources/testcases/regression/load/multiple/run/combined.csv
diff --git a/resources/testcases/load_multiple/run/constant.csv b/resources/testcases/regression/load/multiple/run/constant.csv
similarity index 100%
rename from resources/testcases/load_multiple/run/constant.csv
rename to resources/testcases/regression/load/multiple/run/constant.csv
diff --git a/resources/testcases/load_multiple/sources/dataA.csv b/resources/testcases/regression/load/sources/dataA.csv
similarity index 100%
rename from resources/testcases/load_multiple/sources/dataA.csv
rename to resources/testcases/regression/load/sources/dataA.csv
diff --git a/resources/testcases/load_multiple/sources/dataB.csv b/resources/testcases/regression/load/sources/dataB.csv
similarity index 100%
rename from resources/testcases/load_multiple/sources/dataB.csv
rename to resources/testcases/regression/load/sources/dataB.csv
diff --git a/resources/testcases/load_multiple/sources/dataC.csv b/resources/testcases/regression/load/sources/dataC.csv
similarity index 100%
rename from resources/testcases/load_multiple/sources/dataC.csv
rename to resources/testcases/regression/load/sources/dataC.csv
diff --git a/resources/testcases/load_empty/sources/empty.csv b/resources/testcases/regression/load/sources/empty.csv
similarity index 100%
rename from resources/testcases/load_empty/sources/empty.csv
rename to resources/testcases/regression/load/sources/empty.csv
diff --git a/resources/testcases/repeated_variables/run.rls b/resources/testcases/regression/repeated_variables/run.rls
similarity index 100%
rename from resources/testcases/repeated_variables/run.rls
rename to resources/testcases/regression/repeated_variables/run.rls
diff --git a/resources/testcases/repeated_variables/run/RepeatAll.csv b/resources/testcases/regression/repeated_variables/run/RepeatAll.csv
similarity index 100%
rename from resources/testcases/repeated_variables/run/RepeatAll.csv
rename to resources/testcases/regression/repeated_variables/run/RepeatAll.csv
diff --git a/resources/testcases/repeated_variables/run/RepeatAlternative.csv b/resources/testcases/regression/repeated_variables/run/RepeatAlternative.csv
similarity index 100%
rename from resources/testcases/repeated_variables/run/RepeatAlternative.csv
rename to resources/testcases/regression/repeated_variables/run/RepeatAlternative.csv
diff --git a/resources/testcases/repeated_variables/run/RepeatBody.csv b/resources/testcases/regression/repeated_variables/run/RepeatBody.csv
similarity index 100%
rename from resources/testcases/repeated_variables/run/RepeatBody.csv
rename to resources/testcases/regression/repeated_variables/run/RepeatBody.csv
diff --git a/resources/testcases/repeated_variables/run/RepeatHead.csv b/resources/testcases/regression/repeated_variables/run/RepeatHead.csv
similarity index 100%
rename from resources/testcases/repeated_variables/run/RepeatHead.csv
rename to resources/testcases/regression/repeated_variables/run/RepeatHead.csv
diff --git a/resources/testcases/basic_union/sources/dataA.csv b/resources/testcases/regression/repeated_variables/sources/dataA.csv
similarity index 100%
rename from resources/testcases/basic_union/sources/dataA.csv
rename to resources/testcases/regression/repeated_variables/sources/dataA.csv
diff --git a/resources/testcases/repeated_variables/sources/dataB.csv b/resources/testcases/regression/repeated_variables/sources/dataB.csv
similarity index 71%
rename from resources/testcases/repeated_variables/sources/dataB.csv
rename to resources/testcases/regression/repeated_variables/sources/dataB.csv
index 09baa375a..1cb943320 100644
--- a/resources/testcases/repeated_variables/sources/dataB.csv
+++ b/resources/testcases/regression/repeated_variables/sources/dataB.csv
@@ -3,4 +3,5 @@ B,D,A
 A,C,F
 A,G,Q
 A,Q,Q
-C,D,D
\ No newline at end of file
+C,D,D
+C,D,A
diff --git a/resources/testcases/repeated_variables/sources/dataC.csv b/resources/testcases/regression/repeated_variables/sources/dataC.csv
similarity index 100%
rename from resources/testcases/repeated_variables/sources/dataC.csv
rename to resources/testcases/regression/repeated_variables/sources/dataC.csv
diff --git a/resources/testcases/restricted_block/run.rls b/resources/testcases/regression/restricted_chase/block.rls
similarity index 100%
rename from resources/testcases/restricted_block/run.rls
rename to resources/testcases/regression/restricted_chase/block.rls
diff --git a/resources/testcases/restricted_block/run/result.csv b/resources/testcases/regression/restricted_chase/block/result.csv
similarity index 100%
rename from resources/testcases/restricted_block/run/result.csv
rename to resources/testcases/regression/restricted_chase/block/result.csv
diff --git a/resources/testcases/restricted_datalog_head/run.rls b/resources/testcases/regression/restricted_chase/datalog_head.rls
similarity index 100%
rename from resources/testcases/restricted_datalog_head/run.rls
rename to resources/testcases/regression/restricted_chase/datalog_head.rls
diff --git a/resources/testcases/restricted_datalog_head/run/datalog.csv b/resources/testcases/regression/restricted_chase/datalog_head/datalog.csv
similarity index 100%
rename from resources/testcases/restricted_datalog_head/run/datalog.csv
rename to resources/testcases/regression/restricted_chase/datalog_head/datalog.csv
diff --git a/resources/testcases/restricted_datalog_head/run/result.csv b/resources/testcases/regression/restricted_chase/datalog_head/result.csv
similarity index 100%
rename from resources/testcases/restricted_datalog_head/run/result.csv
rename to resources/testcases/regression/restricted_chase/datalog_head/result.csv
diff --git a/resources/testcases/restricted_doctors/run.rls b/resources/testcases/regression/restricted_chase/doctors.rls
similarity index 100%
rename from resources/testcases/restricted_doctors/run.rls
rename to resources/testcases/regression/restricted_chase/doctors.rls
diff --git a/resources/testcases/restricted_doctors/run/prescription.csv b/resources/testcases/regression/restricted_chase/doctors/prescription.csv
similarity index 100%
rename from resources/testcases/restricted_doctors/run/prescription.csv
rename to resources/testcases/regression/restricted_chase/doctors/prescription.csv
diff --git a/resources/testcases/restricted_head_constant/run.rls b/resources/testcases/regression/restricted_chase/head_constant.rls
similarity index 100%
rename from resources/testcases/restricted_head_constant/run.rls
rename to resources/testcases/regression/restricted_chase/head_constant.rls
diff --git a/resources/testcases/restricted_head_constant/run/result.csv b/resources/testcases/regression/restricted_chase/head_constant/result.csv
similarity index 100%
rename from resources/testcases/restricted_head_constant/run/result.csv
rename to resources/testcases/regression/restricted_chase/head_constant/result.csv
diff --git a/resources/testcases/restricted_multihead/run.rls b/resources/testcases/regression/restricted_chase/multihead.rls
similarity index 100%
rename from resources/testcases/restricted_multihead/run.rls
rename to resources/testcases/regression/restricted_chase/multihead.rls
diff --git a/resources/testcases/restricted_multihead/run/null.csv b/resources/testcases/regression/restricted_chase/multihead/null.csv
similarity index 100%
rename from resources/testcases/restricted_multihead/run/null.csv
rename to resources/testcases/regression/restricted_chase/multihead/null.csv
diff --git a/resources/testcases/restricted_multihead/run/result.csv b/resources/testcases/regression/restricted_chase/multihead/result.csv
similarity index 100%
rename from resources/testcases/restricted_multihead/run/result.csv
rename to resources/testcases/regression/restricted_chase/multihead/result.csv
diff --git a/resources/testcases/restricted_multinulls/run.rls b/resources/testcases/regression/restricted_chase/multinulls.rls
similarity index 100%
rename from resources/testcases/restricted_multinulls/run.rls
rename to resources/testcases/regression/restricted_chase/multinulls.rls
diff --git a/resources/testcases/restricted_multinulls/run/test.csv b/resources/testcases/regression/restricted_chase/multinulls/test.csv
similarity index 100%
rename from resources/testcases/restricted_multinulls/run/test.csv
rename to resources/testcases/regression/restricted_chase/multinulls/test.csv
diff --git a/resources/testcases/restricted_multipieces/run.rls b/resources/testcases/regression/restricted_chase/multipieces.rls
similarity index 100%
rename from resources/testcases/restricted_multipieces/run.rls
rename to resources/testcases/regression/restricted_chase/multipieces.rls
diff --git a/resources/testcases/restricted_multipieces/run/test.csv b/resources/testcases/regression/restricted_chase/multipieces/test.csv
similarity index 100%
rename from resources/testcases/restricted_multipieces/run/test.csv
rename to resources/testcases/regression/restricted_chase/multipieces/test.csv
diff --git a/resources/testcases/restricted_only_nulls/run.rls b/resources/testcases/regression/restricted_chase/only_nulls.rls
similarity index 100%
rename from resources/testcases/restricted_only_nulls/run.rls
rename to resources/testcases/regression/restricted_chase/only_nulls.rls
diff --git a/resources/testcases/restricted_only_nulls/run/result.csv b/resources/testcases/regression/restricted_chase/only_nulls/result.csv
similarity index 100%
rename from resources/testcases/restricted_only_nulls/run/result.csv
rename to resources/testcases/regression/restricted_chase/only_nulls/result.csv
diff --git a/resources/testcases/restricted_recursive/run.rls b/resources/testcases/regression/restricted_chase/recursive/run.rls
similarity index 100%
rename from resources/testcases/restricted_recursive/run.rls
rename to resources/testcases/regression/restricted_chase/recursive/run.rls
diff --git a/resources/testcases/restricted_recursive/run/resultA.csv b/resources/testcases/regression/restricted_chase/recursive/run/resultA.csv
similarity index 100%
rename from resources/testcases/restricted_recursive/run/resultA.csv
rename to resources/testcases/regression/restricted_chase/recursive/run/resultA.csv
diff --git a/resources/testcases/restricted_recursive/run/resultB.csv b/resources/testcases/regression/restricted_chase/recursive/run/resultB.csv
similarity index 100%
rename from resources/testcases/restricted_recursive/run/resultB.csv
rename to resources/testcases/regression/restricted_chase/recursive/run/resultB.csv
diff --git a/resources/testcases/regression/restricted_chase/recursive/sources/dataA.csv b/resources/testcases/regression/restricted_chase/recursive/sources/dataA.csv
new file mode 100644
index 000000000..3167910c9
--- /dev/null
+++ b/resources/testcases/regression/restricted_chase/recursive/sources/dataA.csv
@@ -0,0 +1 @@
+<A>,<B>
diff --git a/resources/testcases/regression/restricted_chase/recursive/sources/dataB.csv b/resources/testcases/regression/restricted_chase/recursive/sources/dataB.csv
new file mode 100644
index 000000000..c63eb3396
--- /dev/null
+++ b/resources/testcases/regression/restricted_chase/recursive/sources/dataB.csv
@@ -0,0 +1 @@
+<B>,<C>
diff --git a/resources/testcases/restricted_simple/run.rls b/resources/testcases/regression/restricted_chase/simple.rls
similarity index 100%
rename from resources/testcases/restricted_simple/run.rls
rename to resources/testcases/regression/restricted_chase/simple.rls
diff --git a/resources/testcases/regression/restricted_chase/simple/result.csv b/resources/testcases/regression/restricted_chase/simple/result.csv
new file mode 100644
index 000000000..759aab0eb
--- /dev/null
+++ b/resources/testcases/regression/restricted_chase/simple/result.csv
@@ -0,0 +1,3 @@
+<A>,<__Null#9223372036854775809>
+<B>,<__Null#9223372036854775810>
+<C>,<__Null#9223372036854775811>
diff --git a/resources/testcases/restricted_block/sources/data.csv b/resources/testcases/regression/restricted_chase/sources/data.csv
similarity index 100%
rename from resources/testcases/restricted_block/sources/data.csv
rename to resources/testcases/regression/restricted_chase/sources/data.csv
diff --git a/resources/testcases/restricted_only_nulls/sources/empty.csv b/resources/testcases/regression/restricted_chase/sources/empty.csv
similarity index 100%
rename from resources/testcases/restricted_only_nulls/sources/empty.csv
rename to resources/testcases/regression/restricted_chase/sources/empty.csv
diff --git a/resources/testcases/stratified_negation/run.rls b/resources/testcases/regression/stratification/binary_negated.rls
similarity index 100%
rename from resources/testcases/stratified_negation/run.rls
rename to resources/testcases/regression/stratification/binary_negated.rls
diff --git a/resources/testcases/stratified_negation/run/result.csv b/resources/testcases/regression/stratification/binary_negated/result.csv
similarity index 100%
rename from resources/testcases/stratified_negation/run/result.csv
rename to resources/testcases/regression/stratification/binary_negated/result.csv
diff --git a/resources/testcases/regression/stratification/regression.yaml b/resources/testcases/regression/stratification/regression.yaml
new file mode 100644
index 000000000..ace8bbe97
--- /dev/null
+++ b/resources/testcases/regression/stratification/regression.yaml
@@ -0,0 +1,4 @@
+pr: 220
+title: Stratified Negation
+tracker: https://github.com/knowsys/nemo/pull/220
+type: feature
diff --git a/resources/testcases/stratified_negation/sources/data.csv b/resources/testcases/regression/stratification/sources/data.csv
similarity index 100%
rename from resources/testcases/stratified_negation/sources/data.csv
rename to resources/testcases/regression/stratification/sources/data.csv
diff --git a/resources/testcases/stratified_negation/sources/equal.csv b/resources/testcases/regression/stratification/sources/equal.csv
similarity index 100%
rename from resources/testcases/stratified_negation/sources/equal.csv
rename to resources/testcases/regression/stratification/sources/equal.csv
diff --git a/resources/testcases/stratified_negation_2/run.rls b/resources/testcases/regression/stratification/unary_negated.rls
similarity index 100%
rename from resources/testcases/stratified_negation_2/run.rls
rename to resources/testcases/regression/stratification/unary_negated.rls
diff --git a/resources/testcases/stratified_negation_2/run/q.csv b/resources/testcases/regression/stratification/unary_negated/q.csv
similarity index 100%
rename from resources/testcases/stratified_negation_2/run/q.csv
rename to resources/testcases/regression/stratification/unary_negated/q.csv
diff --git a/resources/testcases/stratified_negation_2/run/q1.csv b/resources/testcases/regression/stratification/unary_negated/q1.csv
similarity index 100%
rename from resources/testcases/stratified_negation_2/run/q1.csv
rename to resources/testcases/regression/stratification/unary_negated/q1.csv
diff --git a/resources/testcases/stratified_negation_2/run/q2.csv b/resources/testcases/regression/stratification/unary_negated/q2.csv
similarity index 100%
rename from resources/testcases/stratified_negation_2/run/q2.csv
rename to resources/testcases/regression/stratification/unary_negated/q2.csv
diff --git a/resources/testcases/stratified_negation_2/run/r.csv b/resources/testcases/regression/stratification/unary_negated/r.csv
similarity index 100%
rename from resources/testcases/stratified_negation_2/run/r.csv
rename to resources/testcases/regression/stratification/unary_negated/r.csv
diff --git a/resources/testcases/symmetric_transitive_closure/city.csv b/resources/testcases/regression/symmetric_transitive_closure/city.csv
similarity index 100%
rename from resources/testcases/symmetric_transitive_closure/city.csv
rename to resources/testcases/regression/symmetric_transitive_closure/city.csv
diff --git a/resources/testcases/symmetric_transitive_closure/conn.csv b/resources/testcases/regression/symmetric_transitive_closure/conn.csv
similarity index 100%
rename from resources/testcases/symmetric_transitive_closure/conn.csv
rename to resources/testcases/regression/symmetric_transitive_closure/conn.csv
diff --git a/resources/testcases/symmetric_transitive_closure/run.rls b/resources/testcases/regression/symmetric_transitive_closure/run.rls
similarity index 100%
rename from resources/testcases/symmetric_transitive_closure/run.rls
rename to resources/testcases/regression/symmetric_transitive_closure/run.rls
diff --git a/resources/testcases/symmetric_transitive_closure/run/connected.csv b/resources/testcases/regression/symmetric_transitive_closure/run/connected.csv
similarity index 100%
rename from resources/testcases/symmetric_transitive_closure/run/connected.csv
rename to resources/testcases/regression/symmetric_transitive_closure/run/connected.csv
diff --git a/resources/testcases/variable_comparisons/run.rls b/resources/testcases/regression/variable_comparisons/run.rls
similarity index 100%
rename from resources/testcases/variable_comparisons/run.rls
rename to resources/testcases/regression/variable_comparisons/run.rls
diff --git a/resources/testcases/variable_comparisons/run/combine.csv b/resources/testcases/regression/variable_comparisons/run/combine.csv
similarity index 100%
rename from resources/testcases/variable_comparisons/run/combine.csv
rename to resources/testcases/regression/variable_comparisons/run/combine.csv
diff --git a/resources/testcases/variable_comparisons/run/contra.csv b/resources/testcases/regression/variable_comparisons/run/contra.csv
similarity index 100%
rename from resources/testcases/variable_comparisons/run/contra.csv
rename to resources/testcases/regression/variable_comparisons/run/contra.csv
diff --git a/resources/testcases/variable_comparisons/run/equal.csv b/resources/testcases/regression/variable_comparisons/run/equal.csv
similarity index 100%
rename from resources/testcases/variable_comparisons/run/equal.csv
rename to resources/testcases/regression/variable_comparisons/run/equal.csv
diff --git a/resources/testcases/variable_comparisons/run/g_eq.csv b/resources/testcases/regression/variable_comparisons/run/g_eq.csv
similarity index 100%
rename from resources/testcases/variable_comparisons/run/g_eq.csv
rename to resources/testcases/regression/variable_comparisons/run/g_eq.csv
diff --git a/resources/testcases/variable_comparisons/run/g_un.csv b/resources/testcases/regression/variable_comparisons/run/g_un.csv
similarity index 100%
rename from resources/testcases/variable_comparisons/run/g_un.csv
rename to resources/testcases/regression/variable_comparisons/run/g_un.csv
diff --git a/resources/testcases/variable_comparisons/run/l_eq.csv b/resources/testcases/regression/variable_comparisons/run/l_eq.csv
similarity index 100%
rename from resources/testcases/variable_comparisons/run/l_eq.csv
rename to resources/testcases/regression/variable_comparisons/run/l_eq.csv
diff --git a/resources/testcases/variable_comparisons/run/l_un.csv b/resources/testcases/regression/variable_comparisons/run/l_un.csv
similarity index 100%
rename from resources/testcases/variable_comparisons/run/l_un.csv
rename to resources/testcases/regression/variable_comparisons/run/l_un.csv
diff --git a/resources/testcases/variable_comparisons/run/multi.csv b/resources/testcases/regression/variable_comparisons/run/multi.csv
similarity index 100%
rename from resources/testcases/variable_comparisons/run/multi.csv
rename to resources/testcases/regression/variable_comparisons/run/multi.csv
diff --git a/resources/testcases/variable_comparisons/run/r_xy.csv b/resources/testcases/regression/variable_comparisons/run/r_xy.csv
similarity index 100%
rename from resources/testcases/variable_comparisons/run/r_xy.csv
rename to resources/testcases/regression/variable_comparisons/run/r_xy.csv
diff --git a/resources/testcases/variable_comparisons/run/r_yx.csv b/resources/testcases/regression/variable_comparisons/run/r_yx.csv
similarity index 100%
rename from resources/testcases/variable_comparisons/run/r_yx.csv
rename to resources/testcases/regression/variable_comparisons/run/r_yx.csv
diff --git a/resources/testcases/variable_comparisons/run/uneq.csv b/resources/testcases/regression/variable_comparisons/run/uneq.csv
similarity index 100%
rename from resources/testcases/variable_comparisons/run/uneq.csv
rename to resources/testcases/regression/variable_comparisons/run/uneq.csv
diff --git a/resources/testcases/repeated_variables/sources/dataA.csv b/resources/testcases/repeated_variables/sources/dataA.csv
deleted file mode 100644
index b392d4e11..000000000
--- a/resources/testcases/repeated_variables/sources/dataA.csv
+++ /dev/null
@@ -1,4 +0,0 @@
-A,B,C
-B,B,D
-A,E,F
-C,D,D
\ No newline at end of file
diff --git a/resources/testcases/restricted_datalog_head/sources/data.csv b/resources/testcases/restricted_datalog_head/sources/data.csv
deleted file mode 100644
index 8e75edb62..000000000
--- a/resources/testcases/restricted_datalog_head/sources/data.csv
+++ /dev/null
@@ -1,3 +0,0 @@
-<A>,<A>
-<B>,<C>
-<C>,<D>
\ No newline at end of file
diff --git a/resources/testcases/restricted_head_constant/sources/data.csv b/resources/testcases/restricted_head_constant/sources/data.csv
deleted file mode 100644
index 8e75edb62..000000000
--- a/resources/testcases/restricted_head_constant/sources/data.csv
+++ /dev/null
@@ -1,3 +0,0 @@
-<A>,<A>
-<B>,<C>
-<C>,<D>
\ No newline at end of file
diff --git a/resources/testcases/restricted_multihead/sources/data.csv b/resources/testcases/restricted_multihead/sources/data.csv
deleted file mode 100644
index 8e75edb62..000000000
--- a/resources/testcases/restricted_multihead/sources/data.csv
+++ /dev/null
@@ -1,3 +0,0 @@
-<A>,<A>
-<B>,<C>
-<C>,<D>
\ No newline at end of file
diff --git a/resources/testcases/restricted_multinulls/sources/data.csv b/resources/testcases/restricted_multinulls/sources/data.csv
deleted file mode 100644
index 8e75edb62..000000000
--- a/resources/testcases/restricted_multinulls/sources/data.csv
+++ /dev/null
@@ -1,3 +0,0 @@
-<A>,<A>
-<B>,<C>
-<C>,<D>
\ No newline at end of file
diff --git a/resources/testcases/restricted_multipieces/sources/data.csv b/resources/testcases/restricted_multipieces/sources/data.csv
deleted file mode 100644
index 8e75edb62..000000000
--- a/resources/testcases/restricted_multipieces/sources/data.csv
+++ /dev/null
@@ -1,3 +0,0 @@
-<A>,<A>
-<B>,<C>
-<C>,<D>
\ No newline at end of file
diff --git a/resources/testcases/restricted_only_nulls/sources/data.csv b/resources/testcases/restricted_only_nulls/sources/data.csv
deleted file mode 100644
index 8e75edb62..000000000
--- a/resources/testcases/restricted_only_nulls/sources/data.csv
+++ /dev/null
@@ -1,3 +0,0 @@
-<A>,<A>
-<B>,<C>
-<C>,<D>
\ No newline at end of file
diff --git a/resources/testcases/restricted_recursive/sources/dataA.csv b/resources/testcases/restricted_recursive/sources/dataA.csv
deleted file mode 100644
index cf0929143..000000000
--- a/resources/testcases/restricted_recursive/sources/dataA.csv
+++ /dev/null
@@ -1 +0,0 @@
-<A>,<B>
\ No newline at end of file
diff --git a/resources/testcases/restricted_recursive/sources/dataB.csv b/resources/testcases/restricted_recursive/sources/dataB.csv
deleted file mode 100644
index 3bc54418b..000000000
--- a/resources/testcases/restricted_recursive/sources/dataB.csv
+++ /dev/null
@@ -1 +0,0 @@
-<B>,<C>
\ No newline at end of file
diff --git a/resources/testcases/restricted_simple/run/result.csv b/resources/testcases/restricted_simple/run/result.csv
deleted file mode 100644
index aed43a8c4..000000000
--- a/resources/testcases/restricted_simple/run/result.csv
+++ /dev/null
@@ -1,3 +0,0 @@
-A,<__Null#9223372036854775809>
-B,<__Null#9223372036854775810>
-C,<__Null#9223372036854775811>
diff --git a/resources/testcases/restricted_simple/sources/data.csv b/resources/testcases/restricted_simple/sources/data.csv
deleted file mode 100644
index c3eced12b..000000000
--- a/resources/testcases/restricted_simple/sources/data.csv
+++ /dev/null
@@ -1,3 +0,0 @@
-A,A
-B,C
-C,D