# managarm/mlibc

Portable C standard library

Repository: https://github.com/managarm/mlibc
Canonical: https://ross.abutalabs.com/products/mlibc
Language: C
License: NOASSERTION
License Family: other
Topics: c-library, portable, cpp, posix-compatible, x86-64, hacktoberfest
Last push: 2026-08-25T15:09:30+00:00

## Health v2 (maintenance only)
Score: 94/100 (v2, computed 2026-09-03T02:20:16.233290+00:00)
- activity 99, release rhythm 84, longevity 100
- inputs: {"age_days": 3702, "days_push": 8, "days_rel": 31, "gap_med": 35, "n_releases_24m": 8}
- flags: no_license
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 1127, forks 217 (observed 2026-08-28T04:03:41.466903+00:00)

## What it is
mlibc is a portable, fully featured C standard library designed for easy porting to new operating systems via a clean syscall abstraction layer. It aims for glibc/musl feature parity, including full pthread support and GNU extensions, and can run software like Xorg, Mesa, and WebKitGTK.

## Use cases
- port a C standard library to a new hobby operating system
- provide POSIX pthread support on a custom kernel
- run existing Linux software like Xorg or Mesa on a non-Linux OS
- replace glibc or musl with a portable libc for an embedded or research OS
- build a libc with opt-in POSIX and Linux API options

## When to choose
- you are developing a new operating system and need a full-featured C library
- you want glibc/musl-level feature parity rather than a minimal libc like newlib
- you need a clean sysdeps abstraction to plug in custom syscall implementations
- you want to run complex software such as Wayland compositors or web browsers on your OS

## When to avoid
- you are targeting Linux, macOS, or Windows and should use the platform's native libc
- you need a battle-tested, production-hardened libc for a mainstream server environment
- you require a minimal footprint libc for deeply constrained embedded systems
- you depend on features mlibc has not yet implemented, as some features are still missing

## Facets
- artifact type: library
- maturity: active
- function: programming-language, compiler, developer-tools
- domain: operating-systems, developer-tools, cross-platform
- platform: cpp, c, embedded
- tags: c-standard-library, libc, posix, sysdeps, operating-system-ports, glibc-compatible, musl-alternative, linux

## Member repositories
- managarm/mlibc (main) score 94

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:03:41.466903+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 2026-08-30T06:38:49.631022+00:00, confidence not recorded.
  - readme: https://github.com/managarm/mlibc (fetched 2026-08-28T04:03:41.466903+00:00, sha ce3b4980b12f)
- Data as of 2026-08-30T08:39:29.467469+00:00.