facebookexperimental/hermit
Hermit launches linux x86_64 programs in a special, hermetically isolated sandbox to control their execution. Hermit translates normal, nondeterministic behavior, into deterministic, repeatable behavior. This can be used for various applications, including replay-debugging, reproducible artifacts, chaos mode concurrency testing and bug analysis. observed · 2026-08-28
Health v2 · maintenance only
77/100
- Activity 99
- Release rhythm 35
- Longevity 100
Flags: no_releases no_license
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: 1415
- days_rel: n/a
- days_push: 9
- n_releases_24m: 0
Adoption not part of the score
1403 stars · 50 forks observed · 2026-08-28
What it is AI-extracted, prompt v1, taxonomy v1, 2026-08-30, confidence not recorded
Hermit is a Rust CLI tool that runs unmodified x86-64 Linux programs inside a hermetic sandbox, controlling sources of nondeterminism such as thread scheduling, time, randomness, and CPUID. It turns nondeterministic behavior into deterministic, repeatable execution for replay-debugging and concurrency testing.
Use cases
- make a program run deterministically and repeatably
- replay-debug a schedule-sensitive concurrency bug
- chaos-test multithreaded code under controlled scheduling
- produce reproducible build artifacts
- record and replay program execution
- diagnose flaky race conditions
When to choose
- you need repeatable execution of Linux x86-64 programs to debug nondeterministic failures
- you want controlled concurrency or chaos-mode testing of thread scheduling
- you need reproducible artifacts from otherwise nondeterministic builds
When to avoid
- you need a security sandbox - Hermit is explicitly not a security boundary
- your workload relies on uncommon syscalls or complex record/replay
- you need to support architectures or operating systems other than x86-64 Linux
- you need actively developed features - the project is in maintenance mode
Facets
cli-tool · maturity maintenance
simulation testing developer-tools cli developer-tools testing operating-systems performance cli rust deterministic-execution record-and-replay sandbox ptrace reproducibility chaos-testing concurrency-bugs linux
1 source
- readme: https://github.com/facebookexperimental/hermit · fetched 2026-08-28 · 8960ceaccdd5
Member repositories
| Repository | Role | Health v2 |
|---|---|---|
| facebookexperimental/hermit | main | 77 |
For agents
markdown · JSON · MCP: product_card(name="facebookexperimental/hermit")
Data as of 2026-08-30T08:39:29.467469+00:00 · Report a problem