diff --git a/t/t1020-subdirectory.sh b/t/t1020-subdirectory.sh
index 8e22b03cdd..df3183ea1a 100755
--- a/t/t1020-subdirectory.sh
+++ b/t/t1020-subdirectory.sh
@@ -141,13 +141,13 @@ test_expect_success 'GIT_PREFIX for !alias' '
 test_expect_success 'GIT_PREFIX for built-ins' '
 	# Use GIT_EXTERNAL_DIFF to test that the "diff" built-in
 	# receives the GIT_PREFIX variable.
-	printf "dir/" >expect &&
-	printf "#!/bin/sh\n" >diff &&
-	printf "printf \"\$GIT_PREFIX\"" >>diff &&
-	chmod +x diff &&
+	echo "dir/" >expect &&
+	write_script diff <<-\EOF &&
+	printf "%s\n" "$GIT_PREFIX"
+	EOF
 	(
 		cd dir &&
-		printf "change" >two &&
+		echo "change" >two &&
 		GIT_EXTERNAL_DIFF=./diff git diff >../actual
 		git checkout -- two
 	) &&
diff --git a/t/t3404-rebase-interactive.sh b/t/t3404-rebase-interactive.sh
index b79f442acf..d96d0e4c9b 100755
--- a/t/t3404-rebase-interactive.sh
+++ b/t/t3404-rebase-interactive.sh
@@ -555,10 +555,9 @@ test_expect_success 'rebase a detached HEAD' '
 test_expect_success 'rebase a commit violating pre-commit' '
 
 	mkdir -p .git/hooks &&
-	PRE_COMMIT=.git/hooks/pre-commit &&
-	echo "#!/bin/sh" > $PRE_COMMIT &&
-	echo "test -z \"\$(git diff --cached --check)\"" >> $PRE_COMMIT &&
-	chmod a+x $PRE_COMMIT &&
+	write_script .git/hooks/pre-commit <<-\EOF &&
+	test -z "$(git diff --cached --check)"
+	EOF
 	echo "monde! " >> file1 &&
 	test_tick &&
 	test_must_fail git commit -m doesnt-verify file1 &&
diff --git a/t/t5532-fetch-proxy.sh b/t/t5532-fetch-proxy.sh
index d75ef0ea2b..51c9669398 100755
--- a/t/t5532-fetch-proxy.sh
+++ b/t/t5532-fetch-proxy.sh
@@ -12,10 +12,8 @@ test_expect_success 'setup remote repo' '
 	)
 '
 
-cat >proxy <<'EOF'
-#!/bin/sh
-echo >&2 "proxying for $*"
-cmd=$("$PERL_PATH" -e '
+test_expect_success 'setup proxy script' '
+	write_script proxy-get-cmd "$PERL_PATH" <<-\EOF &&
 	read(STDIN, $buf, 4);
 	my $n = hex($buf) - 4;
 	read(STDIN, $buf, $n);
@@ -23,11 +21,16 @@ cmd=$("$PERL_PATH" -e '
 	# drop absolute-path on repo name
 	$cmd =~ s{ /}{ };
 	print $cmd;
-')
-echo >&2 "Running '$cmd'"
-exec $cmd
-EOF
-chmod +x proxy
+	EOF
+
+	write_script proxy <<-\EOF
+	echo >&2 "proxying for $*"
+	cmd=$(./proxy-get-cmd)
+	echo >&2 "Running $cmd"
+	exec $cmd
+	EOF
+'
+
 test_expect_success 'setup local repo' '
 	git remote add fake git://example.com/remote &&
 	git config core.gitproxy ./proxy