diff --git a/.gitignore b/.gitignore
index ad34d8c47b..228ae94255 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,4 +1,3 @@
-*.pyc
 *.bk
 *.swp
 *.swo
@@ -8,5 +7,4 @@ target
 Cargo.lock
 .*.rustfmt
 cranelift.dbg*
-.mypy_cache
 rusty-tags.*
diff --git a/test-all.sh b/test-all.sh
index 7fd2a712b2..cfdde4b858 100755
--- a/test-all.sh
+++ b/test-all.sh
@@ -12,10 +12,6 @@ set -euo pipefail
 #
 # All tests run by this script should be passing at all times.
 
-# Disable generation of .pyc files because they cause trouble for vendoring
-# scripts, and this is a build step that isn't run very often anyway.
-export PYTHONDONTWRITEBYTECODE=1
-
 # Repository top-level directory.
 topdir=$(dirname "$0")
 cd "$topdir"