diff --git a/src/debug.py b/src/debug.py
new file mode 100644
index 0000000..88d21c5
--- /dev/null
+++ b/src/debug.py
@@ -0,0 +1,29 @@
+#! /usr/bin/env python3
+# vim:fenc=utf-8
+
+import sys
+import debugpy
+
+
+def debugger_is_active() -> bool:
+    """Return if the debugger is currently active
+
+    from https://stackoverflow.com/questions/38634988/
+        check-if-program-runs-in-debug-mode
+    """
+    return hasattr(sys, 'gettrace') and sys.gettrace() is not None
+
+
+def breakpoint(wait=True, address="localhost", port=5678):
+    """ Breakpoint that launches debugpy if it's not already active.
+
+    Args:
+        wait: Whether debugpy halts execution until a client attaches.
+        address: The address where debugpy listens for a client.
+        port: The port where debugpy listens for a client.
+    """
+    if not debugger_is_active():
+        debugpy.listen((address, port))
+        if wait:
+            debugpy.wait_for_client()
+    debugpy.breakpoint()