Programming
Haskell foldr vs foldl and When to Use Each One
You wrote a fold over a list of ten million numbers, it worked in GHCi on a small input, and then the real run ate 1.5 GB of...
Your Haskell service passes every load test on a laptop, then falls over in production with "too many clients already" from Postgres or with requests hanging for 30 seconds before timing out.
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Programming
You wrote a fold over a list of ten million numbers, it worked in GHCi on a small input, and then the real run ate 1.5 GB of...
Open Source
Your library builds on your laptop, a stranger opens a pull request, and three days later someone files an issue saying the...
Developer Tools
Your team keeps arguing about where the arrows go in a do block, and every pull request carries twenty lines of whitespace...
Tutorials
You have a function that needs configuration, can fail with a typed error, and has to print to the console, and suddenly every...
Systems
Your Haskell service gets a SIGTERM during a deploy, the process dies mid-request, and somewhere a client sees a 502 while a...
Open Source
You have a library that works on your machine, a few people have asked for it, and now you want to publish a Haskell package...
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Haskell World is written by three developers who came up through systems programming and functional languages and now write about what actually works. We cover Haskell, open source tooling, backend architecture, and the ideas from functional programming that have crossed into mainstream development whether or not most people know it.