My favorite places to work.

How to avoid needing a new case for every typing rule.

A simple technique for implementing type-safe substitution.

... because it’s hard to tell patterns & expressions apart.

Their UI sucks, their docs suck, and they can’t uninstall.

A techno-pessimist “manifesto”, god help me.

She’s survived by many great women writers; here are a few.

On distributed computing, databases and dictionaries.

Every decision that matters is a tradeoff.

Lisp macros add new expression forms. What about patterns?

To use nil well, always distinguish success from failure.

Can monoids be a basis for scoped syntactic extensibility?

Type theory is useful even in dynamic languages.

“Belief” in intuitionistic or classical logic need not be exclusive.

Hygiene is lexical scoping for macros; to implement it, I use syntactic closures.

Recursion + polymorphism + type inference = complicated.

... and monads as tool for model-changing.

Classes are types are predicates are patterns. Dynamic dispatch is pattern-matching, ordered by specificity.