Sometimes I am not so disciplined to run cf-promises on my policy before I commit it. I make a small change and I think I’m golden, but inevitably that breaks things. I wrote a simple commit hook to check policy syntax and stop you from shooting yourself in the foot. You can find  the pre-commit{#a71b90d9d3bb7e4d1f4be225eb124c42527855a3} script over on my github account. I hope you find it useful.