A Couple Million Lines of Haskell: Production Engineering at Mercury | The Haskell Programming Language's blog

What it takes to run 2 million lines of Haskell in production at a fintech company serving 300,000 businesses.

A Couple Million Lines of Haskell: Production Engineering at Mercury Ian Duncan March 30, 2026 [ Haskellers from the trenches ] # Production # Mercury The editors of the Haskell Blog are happy to announce a new series of articles called " Haskellers from the trenches ", where we invite experienced engineers to talk about their subjects of expertise, best practices, and production tales. Engineering rigour and artistic creativity are a fantastic combination, and this series aims to be the synthesis of these two aspects within the Haskell world. I first heard about Haskell when I was sixteen, si

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