はてなブックマーク

For the past few years I’ve been the most senior developer on my teams in Atlassian, in both position (Principal Engineer) and time (almost 9 years) - this means I usually take on the responsibility of managing our software architecture. Architecture is the relationships between systems, which can be fairly tricky to talk about. Probably the best form of communication is a diagram, with boxes repr

I’ve been working on Roy’s new type system which uses a concept called row variables. I’ve also been thinking about TypeScript’s unsound variance issues with its implementation of structural subtyping. That lead to an interesting discussion on Twitter about row polymorphism compared to structural subtyping. Both are trying to type code like the following: let f x = x.a + x.b f {a: 1, b: 2, c: 100}

I’ve been working on Roy’s new type system which uses a concept called row variables. I’ve also been thinking about TypeScript’s unsound variance issues with its implementation of structural subtyping. That lead to an interesting discussion on Twitter about row polymorphism compared to structural subtyping. Both are trying to type code like the following: let f x = x.a + x.b f {a: 1, b: 2, c: 100}

Promises are being debated in the JavaScript community. The most popular specification is Promises/A+. It’s a fairly small specification, containing only a single function: then. The function is heavily overloaded which makes it quite complicated - way more than it has to be. I’ll try to show how category theory can give us a much simpler, more generalised and lawful API! A proper Promise/A+ imple

I’ve been working on a Yesod webapp over the past few weeks. I noticed that the skeleton contained a deploy/Procfile. I also know of a couple of developers that have managed to get Haskell running on Heroku. Heroku Cedar is the polyglot platform which allows you to push any binary that will run on their servers. I first tried using Ubuntu 12.04 to compile the binary. Bad mistake; Heroku uses 10.04