diff --git a/tests/functional/project/test_project_manager_cache_contract.py b/tests/functional/project/test_project_manager_cache_contract.py
new file mode 100644
index 000000000..e9a040eb0
--- /dev/null
+++ b/tests/functional/project/test_project_manager_cache_contract.py
@@ -0,0 +1,157 @@
+from types import SimpleNamespace
+
+from ape.managers.project import ProjectManager
+from ape.types import ContractType
+
+
+class RecordingCompiler:
+    def __init__(self):
+        self.calls = []
+
+    def compile(self, paths):
+        paths = list(paths)
+        self.calls.append(tuple(str(path) for path in paths))
+        return [
+            ContractType(
+                contractName=f"{path.stem}:{path.read_text()}",
+                sourceId=str(path),
+                abi=[],
+            )
+            for path in paths
+        ]
+
+
+class CompilerManagerStub:
+    def __init__(self, compiler):
+        self.compiler = compiler
+        self.registered_compilers = {".foo": compiler}
+
+    def compile(self, paths):
+        return {
+            contract.contractName: contract
+            for contract in self.compiler.compile(paths)
+        }
+
+
+def make_project(tmp_path, compiler=None):
+    compiler = compiler or RecordingCompiler()
+    config = SimpleNamespace(PROJECT_FOLDER=tmp_path, name="", dependencies=[])
+    return ProjectManager(tmp_path, config, CompilerManagerStub(compiler)), compiler
+
+
+def test_missing_contract_directory_has_no_unknown_extensions(tmp_path):
+    project, _ = make_project(tmp_path)
+
+    assert project.sources_missing is True
+    assert project.extensions_with_missing_compilers == []
+
+
+def test_empty_contract_directory_is_reported_as_missing(tmp_path):
+    project, _ = make_project(tmp_path)
+    (tmp_path / "contracts").mkdir()
+    assert project.sources_missing is True
+    assert project.extensions_with_missing_compilers == []
+
+
+def make_nested_sources(tmp_path):
+    project, _ = make_project(tmp_path)
+    contracts = tmp_path / "contracts"
+    (contracts / "nested").mkdir(parents=True)
+    for relative in (
+        "z.foo",
+        "a.bar",
+        "q.zeta",
+        "nested/m.foo",
+        "nested/b.bar",
+        "nested/a.alpha",
+    ):
+        (contracts / relative).write_text(relative)
+    return project, contracts
+
+
+def test_sources_are_recursive_and_sorted(tmp_path):
+    project, contracts = make_nested_sources(tmp_path)
+    assert [path.relative_to(contracts).as_posix() for path in project.sources] == [
+        "nested/m.foo",
+        "z.foo",
+    ]
+
+
+def test_unknown_extensions_are_recursive_and_sorted(tmp_path):
+    project, _ = make_nested_sources(tmp_path)
+    assert project.extensions_with_missing_compilers == [".alpha", ".bar", ".zeta"]
+
+
+def test_corrupt_manifest_cache_is_ignored_and_rebuilt(tmp_path):
+    project, compiler = make_project(tmp_path)
+    contracts = tmp_path / "contracts"
+    contracts.mkdir()
+    source = contracts / "one.foo"
+    source.write_text("v1")
+    cache = tmp_path / ".build" / "__local__.json"
+    cache.parent.mkdir()
+    cache.write_text("not-json")
+
+    loaded = project.load_contracts()
+
+    assert set(loaded) == {"one:v1"}
+    assert compiler.calls == [(str(source),)]
+
+
+def setup_cached_sources(tmp_path):
+    project, compiler = make_project(tmp_path)
+    contracts = tmp_path / "contracts"
+    contracts.mkdir()
+    first = contracts / "first.foo"
+    second = contracts / "second.foo"
+    first.write_text("v1")
+    second.write_text("v1")
+
+    initial = project.load_contracts()
+    assert set(initial) == {"first:v1", "second:v1"}
+    assert compiler.calls[-1] == (str(first), str(second))
+    return project, compiler, contracts, first, second
+
+
+def test_incremental_cache_compiles_only_changed_and_new_sources(tmp_path):
+    project, compiler, contracts, first, second = setup_cached_sources(tmp_path)
+    first.write_text("v2")
+    third = contracts / "third.foo"
+    third.write_text("v1")
+    updated = project.load_contracts()
+    assert compiler.calls[-1] == (str(first), str(third))
+    assert "second:v1" in updated
+    assert "third:v1" in updated
+
+
+def test_changed_source_replaces_its_stale_contract_types(tmp_path):
+    project, _, _, first, _ = setup_cached_sources(tmp_path)
+    first.write_text("v2")
+    updated = project.load_contracts()
+    assert "first:v1" not in updated
+    assert updated["first:v2"].sourceId == str(first)
+
+
+def test_deleted_source_drops_its_cached_contract_types(tmp_path):
+    project, _, _, _, second = setup_cached_sources(tmp_path)
+    second.unlink()
+    project.load_contracts()
+
+    reloaded_project, _ = make_project(tmp_path)
+    after_delete = reloaded_project.load_contracts()
+    assert set(after_delete) == {"first:v1"}
+
+
+def test_force_rebuild_recompiles_all_current_sources(tmp_path):
+    project, compiler = make_project(tmp_path)
+    contracts = tmp_path / "contracts"
+    contracts.mkdir()
+    first = contracts / "first.foo"
+    second = contracts / "second.foo"
+    first.write_text("v1")
+    second.write_text("v1")
+
+    project.load_contracts()
+    project.load_contracts(use_cache=False)
+
+    assert compiler.calls[-1] == (str(first), str(second))
diff --git a/mimo_test_command.sh b/mimo_test_command.sh
new file mode 100755
--- /dev/null
+++ b/mimo_test_command.sh
@@ -0,0 +1,6 @@
+#!/bin/bash
+set -euo pipefail
+
+
+pytest -q tests/functional/project/test_project_manager_cache_contract.py
+