diff --git a/env.ps1 b/env.ps1
index 9ed5515..d1ea597 100644
--- a/env.ps1
+++ b/env.ps1
@@ -36,7 +36,7 @@
 Function Global:dotest_ci { pytest -q -n auto --hypothesis-profile=ci }
 Function Global:dotest_long { pytest -q -n 4 --hypothesis-profile=long }
 Function Global:docheck { dotidy && dolint && dotest }
-Function _domut { mutmut run --paths-to-mutate "src/syntax.py src/tokenize.py src/parse.py" $args }
-Function Global:domut { _domut }
-Function Global:domut_ci { _domut --no-progress | Select-String -Not "Running\.\.\.$" }
+Function Global:_envps1_domut { mutmut run --paths-to-mutate "src/syntax.py src/tokenize.py src/parse.py" $args }
+Function Global:domut { _envps1_domut }
+Function Global:domut_ci { _envps1_domut --no-progress | Select-String -Not "Running\.\.\.$" }
 Function Global:dobuild { python build.py }