diff --git a/internal/tools/tools.go b/internal/tools/tools.go
new file mode 100644
index 00000000..d4ad233b
--- /dev/null
+++ b/internal/tools/tools.go
@@ -0,0 +1,13 @@
+//go:build tools
+
+// This file is a bit of a hacky workaround a limitation of `go mod tidy`. It
+// will never be built, but `go mod tidy` will see the packages imported here as
+// dependencies of the Flamenco project, and not remove them from `go.mod`.
+
+package main
+
+import (
+	// Go code generators:
+	_ "github.com/deepmap/oapi-codegen/cmd/oapi-codegen"
+	_ "github.com/golang/mock/mockgen"
+)