diff --git a/Makefile.toml b/Makefile.toml
index da40cac..ab21fcb 100644
--- a/Makefile.toml
+++ b/Makefile.toml
@@ -1,11 +1,14 @@
 [env]
 # Set BROWSER="firefox" if not already defined.
+# All browser targets are defined in `source/types.d.ts` as a global `$browser`.
 BROWSER = { condition = { env_not_set = ["BROWSER"] }, value = "firefox" }
+# Set NODE_ENV="development" if not already defined.
+# Either "development" or "production" should be used.
+NODE_ENV = { condition = { env_not_set = ["NODE_ENV"] }, value = "development" }
 
 # Start a browser instance that will reload the extension when changes are made.
 [tasks.dev]
 clear = true
-env = { NODE_ENV = "development" }
 dependencies = ["build"]
 command = "pnpm"
 args = ["conc", "-c=auto", "-k", "makers watch", "makers run"]