diff --git a/Dockerfile b/Dockerfile
deleted file mode 100644
index 6ab1710..0000000
--- a/Dockerfile
+++ /dev/null
@@ -1,7 +0,0 @@
-FROM python:alpine AS base
-
-RUN \
-    --mount=type=cache,target=/var/cache/apk \
-    apk add -U make
-
-WORKDIR /app
\ No newline at end of file
diff --git a/Makefile b/Makefile
index 9391a51..c39ce93 100644
--- a/Makefile
+++ b/Makefile
@@ -1,7 +1,19 @@
+SRC := spiff_element_units
+TESTS := tests
+
 DEV_SERVICE := dev
 
+MY_USER := $(shell id -u)
+MY_GROUP := $(shell id -g)
+ME := $(MY_USER):$(MY_GROUP)
+AS_ME := docker compose run -u $(ME) $(DEV_SERVICE)
+
 .PHONY: all
 all: dev-env
 
 dev-env:
 	docker compose build --progress=plain $(DEV_SERVICE)
+
+.PHONY: tests
+tests:
+	$(AS_ME) unittest-parallel -vs $(TESTS) -p test_*.py -t .
diff --git a/dev/Dockerfile b/dev/Dockerfile
new file mode 100644
index 0000000..a5f68b6
--- /dev/null
+++ b/dev/Dockerfile
@@ -0,0 +1,13 @@
+FROM python:alpine AS base
+
+RUN \
+    --mount=type=cache,target=/var/cache/apk \
+    apk add -U make
+
+RUN python -m pip install --upgrade pip
+
+WORKDIR /app
+
+COPY dev/requirements.txt .
+
+RUN pip install --no-cache-dir -r requirements.txt
\ No newline at end of file
diff --git a/dev/requirements.txt b/dev/requirements.txt
new file mode 100644
index 0000000..f70d4d2
--- /dev/null
+++ b/dev/requirements.txt
@@ -0,0 +1 @@
+unittest-parallel == 1.5.3
diff --git a/docker-compose.yml b/docker-compose.yml
index 6cf909f..32e99f2 100644
--- a/docker-compose.yml
+++ b/docker-compose.yml
@@ -2,4 +2,8 @@ services:
   dev:
     container_name: spiff-element-units-dev
     build:
-      dockerfile: Dockerfile
\ No newline at end of file
+      context: .
+      dockerfile: dev/Dockerfile
+    volumes:
+      - ./spiff_element_units:/app/spiff_element_units
+      - ./tests:/app/tests
\ No newline at end of file
diff --git a/spiff_element_units/__init__.py b/spiff_element_units/__init__.py
index e69de29..feb40fd 100644
--- a/spiff_element_units/__init__.py
+++ b/spiff_element_units/__init__.py
@@ -0,0 +1,2 @@
+def this_returns_true():
+    return True
diff --git a/tests/test_sanity.py b/tests/test_sanity.py
new file mode 100644
index 0000000..69ec81f
--- /dev/null
+++ b/tests/test_sanity.py
@@ -0,0 +1,7 @@
+from unittest import TestCase
+
+from spiff_element_units import this_returns_true
+
+class SanityTest(TestCase):
+    def test_it_returns_true(self):
+        assert this_returns_true()