Try adding some random stuff that you get for basically free with your choice of backend / implementation.
This will waste their time if its a harder problem with their backend / implementation.
Another fun thing you can do is using something that looks like a 3rd-party service/API, but is really just another domain controlled by your company. Make it something specific to your business, so they'll be tempted to use it.
IF they use it, the least you can do is terminate their access at an inconvenient time. This will frustrate their customers as they scramble to do their own implementation.
Final thing you can do is not doing incremental updates, but instead doing big rollouts with many features at once.
That way they'll always be weeks to months behind you.
Basically, when someone is following you, mine the path to the point that it's cheaper and more effective for them to find their own.
Edit: Bonus round is talking about some near-useless feature on your dev blog that would be hilariously expensive and complicated to build, without actually building it. Hope they waste time on it.