diff --git a/dev.py b/dev.py
index f5f8ad9..0d9fd7f 100755
--- a/dev.py
+++ b/dev.py
@@ -1,10 +1,20 @@
 #!/usr/bin/env python3
 
+import shutil
 import subprocess
 import serial
 import sys
 from pathlib import Path
 
+
+def mpremote_base():
+    """mpremote on PATH, or same interpreter as this script (e.g. pipenv venv)."""
+    exe = shutil.which("mpremote")
+    if exe:
+        return [exe]
+    return [sys.executable, "-m", "mpremote"]
+
+
 print(sys.argv)
 
 # Extract port (first arg if it's not a command)
@@ -19,17 +29,20 @@ for cmd in sys.argv[1:]:
     match cmd:
         case "src":
             if port:
-                subprocess.call(["mpremote", "connect", port, "fs", "cp", "-r", ".", ":" ], cwd="src")
+                subprocess.call(
+                    [*mpremote_base(), "connect", port, "fs", "cp", "-r", ".", ":"],
+                    cwd="src",
+                )
             else:
                 print("Error: Port required for 'src' command")
         case "lib":
             if port:
-                subprocess.call(["mpremote", "connect", port, "fs", "cp", "-r", "lib", ":" ])
+                subprocess.call([*mpremote_base(), "connect", port, "fs", "cp", "-r", "lib", ":"])
             else:
                 print("Error: Port required for 'lib' command")
         case "ls":
             if port:
-                subprocess.call(["mpremote", "connect", port, "fs", "ls", ":" ])
+                subprocess.call([*mpremote_base(), "connect", port, "fs", "ls", ":"])
             else:
                 print("Error: Port required for 'ls' command")
         case "reset":
@@ -49,7 +62,7 @@ for cmd in sys.argv[1:]:
                 print("Error: Port required for 'follow' command")
         case "db":
             if port:
-                subprocess.call(["mpremote", "connect", port, "fs", "cp", "-r", "db", ":" ])
+                subprocess.call([*mpremote_base(), "connect", port, "fs", "cp", "-r", "db", ":"])
             else:
                 print("Error: Port required for 'db' command")
         case "test":
@@ -64,7 +77,7 @@ for cmd in sys.argv[1:]:
                     for test_file in test_files:
                         print(f"Running {test_file}")
                         code = subprocess.call(
-                            ["mpremote", "connect", port, "run", test_file]
+                            [*mpremote_base(), "connect", port, "run", test_file]
                         )
                         if code != 0:
                             failed.append((test_file, code))
@@ -73,6 +86,8 @@ for cmd in sys.argv[1:]:
                         for test_file, code in failed:
                             print(f"  {test_file} (exit {code})")
                 else:
-                    subprocess.call(["mpremote", "connect", port, "run", "test/all.py"])
+                    subprocess.call(
+                        [*mpremote_base(), "connect", port, "run", "test/all.py"]
+                    )
             else:
                 print("Error: Port required for 'test' command")