# fitzgen/bumpalo

A fast bump allocation arena for Rust

Repository: https://github.com/fitzgen/bumpalo
Canonical: https://ross.abutalabs.com/products/bumpalo
Homepage: https://docs.rs/bumpalo
Language: Rust
License: Apache-2.0
License Family: permissive
Last push: 2026-07-23T18:54:44+00:00

## Health v2 (maintenance only)
Score: 75/100 (v2, computed 2026-09-03T02:20:16.233290+00:00)
- activity 94, release rhythm 35, longevity 100
- inputs: {"age_days": 2844, "days_push": 41, "days_rel": null, "gap_med": null, "n_releases_24m": 0}
- flags: no_releases
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 2310, forks 156 (observed 2026-08-28T04:06:35.960444+00:00)

## What it is
bumpalo is a fast bump allocation arena library for Rust that allocates objects by advancing a pointer through memory chunks. It enables extremely fast allocation and mass deallocation, at the cost of not invoking Drop or supporting individual object deallocation.

## Use cases
- fast arena allocation in Rust
- allocate many short-lived objects efficiently
- phase-oriented batch deallocation of objects
- arena-allocated collections like Vec and String
- reduce allocator overhead in parsers and compilers
- allocate objects without individual free calls

## When to choose
- you allocate many objects in a phase and free them all together
- allocation speed is a bottleneck and objects don't need Drop
- you want arena-based collections that allocate inside a shared arena

## When to avoid
- you need to deallocate individual objects or reclaim memory mid-phase
- your objects have Drop implementations that must run on free
- you need general-purpose dynamic memory management

## Facets
- artifact type: library
- maturity: stable
- function: developer-tools, concurrency
- domain: developer-tools, performance
- platform: rust, cross-platform
- tags: arena-allocation, bump-allocator, memory-management, no-std, performance, algorithms

## Member repositories
- fitzgen/bumpalo (main) score 75

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:06:35.960444+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 2026-08-30T02:39:33.528219+00:00, confidence not recorded.
  - readme: https://github.com/fitzgen/bumpalo (fetched 2026-08-28T04:06:35.960444+00:00, sha 0b177a941762)
  - homepage: https://docs.rs/bumpalo (fetched 2026-08-29T10:19:46.925710+00:00, sha 0292a5a1a8f3)
  - site_page: https://docs.rs/ (fetched 2026-08-29T10:19:46.935035+00:00, sha 6bcb786a7e4e)
  - site_page: https://docs.rs/crate/bumpalo/latest (fetched 2026-08-29T10:19:46.937050+00:00, sha 6a3309a03727)
  - site_page: https://docs.rs/crate/bumpalo/latest/features (fetched 2026-08-29T10:19:46.938939+00:00, sha c78e32a5c048)
  - site_page: https://docs.rs/about (fetched 2026-08-29T10:19:46.940726+00:00, sha 29ab7986fbf5)
  - site_page: https://docs.rs/about/badges (fetched 2026-08-29T10:19:46.942661+00:00, sha 6588cac258af)
  - site_page: https://docs.rs/about/builds (fetched 2026-08-29T10:19:46.944384+00:00, sha 811231ca4680)
  - site_page: https://docs.rs/about/metadata (fetched 2026-08-29T10:19:46.946150+00:00, sha 0dcdccb2b2b2)
  - site_page: https://docs.rs/about/redirections (fetched 2026-08-29T10:19:46.947914+00:00, sha 1b1efd93105f)
- Data as of 2026-08-30T08:39:29.467469+00:00.