Earlier quoted context omitted.
The site doesn't provide recipes, it provides endpoints (API calls) that users can write recipes to use. How it worked until now: 1) IFTTT wrote glue code to interface with a site's published API, and IFTTT could then write recipes to use the site. IFTTT thus stitched together other sites published APIs as a service. How IFTTT has decided it will work from now on: 1) IFTTT comes to you and orders you to write private…
Wouldn't you be performing this work because you believe it will facilitate the transfer of traffic to your site? Aren't you comitting to make changes as and when ifttt change their API so that you can continue to receive their calls? Sites/services can just walk away if they don't want the traffic. No one's obliged to pay or do anything they don't want to.
Later, after putting a bizarre legal agreement in front of him to sign, IFTTT announced that Pinboard would stop working on their service in a manner that made it sound an awful lot like Maciej had just decided to stop supporting IFTTT. In reality, all the agency in this relationship belonged to IFTTT.