Releases

v0.1.0 2026-08-06 release notes ↓

What changed in this release, the official binaries, their SHA-256 checksums, and how to verify both before you trust them. The one-line installer does this for you; if you are packaging kapsl for other people, do it yourself.

What changed

Anything under SECURITY changes what a tool can reach — read those before upgrading in CI. Older releases are in the rail; each one has its own binaries and notes.

SECURITY

Environment variables are now an explicit allow-list. Only TERM and LANG cross in by default, plus whatever a tool declares.

ADDED

--platform to pin a container arch, for ARM hosts running x86-only tools.

The env = ["VAR"] tool-index entry — a per-tool env allow-list, honored before the defaults.

kapsl --update --check for CI: exit 1 if the index moved, print nothing else.

CHANGED

First-run output now reports the runtime it found, before the tool index is fetched — so a broken runtime fails in 300 ms, not after a 40 MB pull.

The shim no longer sets DOCKER_CONFIG; the container runtime gets a private, throwaway config instead.

kapsl.toml reads caps as a repeatable key. The old single-string form still parses, so nothing breaks.

FIXED

A tool exiting non-zero no longer leaves its container behind. The runtime cleans up on every exit path now, including SIGINT mid-run.

Quoted arguments with leading - reached the tool instead of being parsed as kapsl flags.

The port picker no longer grabs ports other processes have open, and it says so when it can't find one.

NOTES

v0.1.0 is the first release with signed binaries. Everything earlier was unsigned — this is the floor, not the regression.

Binaries

Platform	File	Size	SHA-256
linux/amd64	kapsl-0.1.0-linux-amd64.tar.gz	6.2 MB	9f2a4c81…c41b
linux/arm64	kapsl-0.1.0-linux-arm64.tar.gz	5.8 MB	4b8e0d37…99f2
darwin/amd64	kapsl-0.1.0-darwin-amd64.tar.gz	6.4 MB	7c1f9a20…e5b8
darwin/arm64	kapsl-0.1.0-darwin-arm64.tar.gz	5.9 MB	d3a5c7f4…18d6
windows/amd64	kapsl-0.1.0-windows-amd64.zip	6.8 MB	a94e2b61…f03c

checksums.txt ↗ checksums.txt.sig ↗ All assets on GitHub ↗

Verify a download

Two checks: the checksum proves the file is intact, the signature proves we published it. The second is the one that matters — a matching hash from a tampered checksums file proves nothing.

Missing cosign or sha256sum? If any kapsl is already on the machine, run them through it — kapsl cosign … — and verify the next release with the last one. Nothing to install on the host, and the verifying tool is itself a signed, scanned image.

$ kapsl sha256sum -c checksums.txt --ignore-missing
kapsl-0.1.0-linux-amd64.tar.gz: OK
$ kapsl cosign verify-blob --signature checksums.txt.sig \
    --certificate-identity-regexp 'https://github.com/kapsl-sh/kapsl/.*' \
    kapsl-0.1.0-linux-amd64.tar.gz
Verification: valid signature

Provenance

Signing identity	github.com/kapsl-sh/kapsl/ci
Transparency log	Sigstore Fulcio — pinned at verify time, not build time
Build attestation	kapsl-0.1.0.sbom (SPDX 2.3) — every dependency is listed
Reproducible	Building release/Dockerfile twice yields identical bytes; CI checks this on every PR

Air-gapped or mirroring internally? kapsl --offline needs no network at all, and the release archive can be copied like any other file — signature and all.