Changelog

All notable changes to sb-runtime are documented here. Format follows Keep a Changelog; the project follows Semantic Versioning once it hits v1.0.

Unreleased

First public preview. Design-partner release.

sb-cli — the sb binary with three subcommands: exec, verify, keys generate.
sb-sandbox crate — OS-native sandbox primitives.
- Linux x86_64 backend: Landlock ABI V2 (filesystem read / write / exec) + seccomp-BPF (strict allowlist of ~70 syscalls by default; permissive deny-list mode also available).
- Linux aarch64: refuses-to-run with a clear error rather than silently degrading. See issue #1.
- macOS + Windows: stubs. --allow-unsandboxed lets the other layers (Cedar + receipts) fire without OS isolation on those platforms.
sb-policy crate — Cedar-backed policy evaluator.
sb-receipt crate — Ed25519-signed, JCS-canonical, hash-chained receipts. Zero-I/O, pure-crypto. Compatible with @veritasacta/verify and the IETF draft-farley-acta-signed-receipts.
examples/basic/ — minimal "allow-list of commands" Cedar policy with smoke-test instructions.
examples/agt-integration/ — Python shim (SbRuntimeSkill) that drops into Microsoft's Agent Governance Toolkit in place of openshell_agentmesh.skill.GovernanceSkill. Same public interface; swap via config. Addresses AGT issue #748.
CI — cargo fmt, cargo clippy, cargo test, and an end-to-end Linux smoke run on push / PR. Cross-compile to x86_64-linux / x86_64-macos / aarch64-macos on tagged releases.
Community files — CONTRIBUTING.md, SECURITY.md, DESIGN.md with roadmap + open questions.

See DESIGN.md#known-limitations-v01 for the full list. Headlines:

Linux x86_64 only in this release.
Syscall allowlist is hand-curated; some programs will hit missing syscalls (particularly statx, ioctl, newer getrandom variants).
Network policy is coarse: loopback-or-nothing via seccomp. Landlock network rules (kernel ≥ 6.7) land in v0.2.
Receipt chains are single-issuer. Multi-issuer chains are issue #4.
sb exec runs the command it evaluates; a pure-evaluation --dry-run mode is issue #2.

@tomjwxf — core scaffold, Linux backend, Cedar integration, receipt format, AGT shim.

You? We're actively looking for design partners — see CONTRIBUTING.md.