# lfe/lfe

Lisp Flavoured Erlang (LFE)

Repository: https://github.com/lfe/lfe
Canonical: https://ross.abutalabs.com/products/lfe
Language: Erlang
License: Apache-2.0
License Family: permissive
Last push: 2026-08-05T21:46:32+00:00

## Health v2 (maintenance only)
Score: 88/100 (v2, computed 2026-09-03T02:20:16.233290+00:00)
- activity 96, release rhythm 72, longevity 100
- inputs: {"age_days": 6588, "days_push": 28, "days_rel": 28, "gap_med": 118, "n_releases_24m": 4}
- flags: none
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 2453, forks 147 (observed 2026-08-28T04:06:53.053298+00:00)

## What it is
Lisp Flavoured Erlang (LFE) is a Lisp syntax front-end to the Erlang compiler, producing code fully compatible with normal Erlang. It includes a REPL, compiler (lfec), script runner (lfescript), and documentation tooling running on the Erlang VM.

## Use cases
- write erlang programs with lisp syntax
- run a lisp repl on the beam vm
- compile lisp code to erlang
- script the erlang vm with lisp
- use erlang otp libraries from lisp
- learn functional programming on the erlang vm

## When to choose
- you want Lisp semantics with Erlang's concurrency, fault tolerance, and OTP ecosystem
- you need full interoperability with existing Erlang code and libraries
- you prefer s-expression syntax and macros over Erlang's syntax

## When to avoid
- your team only knows standard Erlang or Elixir and has no Lisp experience
- you need extensive tooling and editor support comparable to mainstream BEAM languages
- you want a language with a large community and abundant learning resources

## Facets
- artifact type: cli-tool
- maturity: active
- function: compiler, interpreter, programming-language, cli
- domain: programming-languages, compilers, developer-tools
- platform: windows, cli, cross-platform
- tags: lisp, erlang, beam, repl, functional-programming, lisp-dialect, command-line, linux, macos

## Member repositories
- lfe/lfe (main) score 88

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:06:53.053298+00:00.
- Health v2: computed from the inputs above; adoption is never an input.
- Inferred fields (summary, facets, guidance): AI-extracted, prompt v1, taxonomy v1, on 2026-08-30T02:30:09.201868+00:00, confidence not recorded.
  - readme: https://github.com/lfe/lfe (fetched 2026-08-28T04:06:53.053298+00:00, sha e919ec5d44e0)
- Data as of 2026-08-30T08:39:29.467469+00:00.