Tom Ellis reclassifies Bluefin, a Haskell library he released in early 2024, as a "capability system" rather than merely an effect system. Bluefin differs from traditional effect systems like effectful by encoding effects as value-level arguments instead of type-level constraints, aligning it more closely with the classical notion of capability-based security frameworks.
Background
Bluefin is a Haskell library for managing side effects through an IO-wrapper effect system, initially inspired by the effectful library. The concept of capability systems dates back decades in computer science, originally applied to operating system security models.
- Source
- Lobsters
- Published
- Sep 2, 2026 at 02:09 PM
- Score
- 5.0 / 10