plfa/plfa.github.io resource
An introduction to programming language theory in Agda observed · 2026-08-28
Health v2 · maintenance only
67/100
- Activity 99
- Release rhythm 8
- Longevity 100
How is this computed?
round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10) — computed 2026-09-03. Adoption (stars, forks) is never an input.
- gap_med: n/a
- age_days: 3463
- days_rel: n/a
- days_push: 9
- n_releases_24m: 0
Adoption not part of the score
1513 stars · 353 forks observed · 2026-08-28
What it is AI-extracted, prompt v1, taxonomy v1, 2026-08-30, confidence not recorded
Programming Language Foundations in Agda (PLFA) is a free online textbook teaching programming language theory using the Agda proof assistant. It covers logical foundations, operational and denotational semantics, and type systems, with all code formalized and verified in Agda.
Use cases
- learn programming language theory with a proof assistant
- study lambda calculus semantics formally
- learn Agda through a structured textbook
- formally verify type soundness and progress/preservation
- understand bidirectional type inference and de Bruijn representations
- teach a course on formal semantics of programming languages
When to choose
- you want an interactive, executable introduction to PL theory in Agda
- you prefer learning semantics by proving theorems rather than reading prose alone
- you need a free, open (CC-BY-4.0) textbook for self-study or coursework
When to avoid
- you want a tool or library rather than a book
- you need Coq, Lean, or Isabelle instead of Agda
- you are not prepared to install specific pinned versions of GHC, Cabal, and Agda to run the exercises
Facets
learning-resource · maturity active
documentation interpreter type-system programming-languages tutorials education compilers cross-platform cli agda proof-assistant programming-language-theory type-theory denotational-semantics lambda-calculus interactive-textbook formal-methods
2 sources
- readme: https://github.com/plfa/plfa.github.io · fetched 2026-08-28 · 46a1e5191a49
- homepage: https://plfa.github.io · fetched 2026-08-29 · d2896e7d6094
Member repositories
| Repository | Role | Health v2 |
|---|---|---|
| plfa/plfa.github.io | main | 67 |
For agents
markdown · JSON · MCP: product_card(name="plfa/plfa.github.io")
Data as of 2026-08-30T08:39:29.467469+00:00 · Report a problem