Sustainable APIs
A well designed system can provide utility while reducing overall energy use. Also in this newsletter: Clerk's API Keys product, Express 5.0, Ktor, and an illustrative HTTP code cheat sheet.
The only thing I love more than a well-designed API is one that's built with performance and sustainability in mind.
Tom Kerkhove from Microsoft's Azure API Management team appears in the latest episode of the Enviorment Variables. A great conversation about how well-designed APIs can reduce energy use and improve a system's efficiency. An excellent conversion on how caching, throttling, and observability improve reliability and developer experience.
Really nailing how choices on your API layer can have a massive impact on cost, performance and sustainability at scale.
-- Alexander

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API News, links, and tools from around the web
Terrible Train APIs
Who doesn't love an API and trains... turns out the people building the API for the trains. An excellent thread from Luc Casonato (creator of Fresh) on the APIs from two Italian high-speed train operators. We got XML in JSON, spelling mistakes, hardcoded passwords and more.
Clerk: API Keys Public Beta
Clerk is way more than simplified Auth and React components; it's a complete user management setup, and it now includes API keys. With a simple flick of the switch, allow users to create, view and revoke API keys to access your API. Their backend SDK has a great setup, making scope, claims and expiration easy. Personally, I always loved using Clerk, and it's great to see this addition.
Express 5 Migration
Express 5 has been out a while now, but we all know migration can be complex. Thankfully, there are some incredible Express Codemods to make your transition so much easier.
Cheat Sheet
Who doesn't love a good cheat sheet? Well, MDN has got you covered with a lovely PDF of all the different HTTP Codes with Emoji pairings. I have linked the PDF from GitHub for a nice high-resolution version.
Ktor 3.4.0
My favourite framework for building APIs in Kotlin has recently dropped a new release with their OpenAPI generation now fully ironed out. The releases also include a bunch of great features, including Zstd compression support, an HTTP request lifecycle plugin, and more.
APIs You Won't Hate
Articles written and shared in our free Slack community.
OpenAPI.Tools
It's been almost two weeks since we dropped our new OpenAPI.Tools website and we have already had some excellent contributions. Remember, if your favourite tool is missing or needs an update, it only takes a small PR.
APIs You Won't Hate Community
We love a good community submission. If you're an APIs You Won't Hate member, and you'd like to have your work featured in the community section of the newsletter, send us a message in our free Slack community to get the ball rolling.
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Become a member todayThanks so much to our members: Kin L, Juxt, Alex R, Nolan S, Brandon K, Frank, James D, Bill D, and Abdelhadi . Your support means the world to us!
✌️ Until next time,
Alexander, Phil & Mike