Changelog

Durable, self-healing apps

Promote a workload to a named app the daemon manages over time — the answer to "my sandbox died on a daemon restart." See apps.md.

• Durable apps — crucible app create <name> --image … -p H:G --restart always --health http:PORT[:PATH]. The daemon keeps a healthy instance of the app, restarts it on failure with exponential backoff + a crash-loop guard, health-checks it (http/tcp), and — the headline — re-creates it from persisted desired state after a daemon restart or host reboot (desired-state reconcile, not live-VM re-attach; a bbolt control-plane store + a reconcile loop).
• Full surface — app ls|get|rm|logs|exec|shell, REST /apps, the Go SDK (CreateApp/ListApps/GetApp/DeleteApp + an App handle), and four MCP tools (create_app/list_apps/get_app/delete_app), bringing the MCP surface to 19 tools.
• The ephemeral sandbox primitive is unchanged; forks stay ephemeral by design.

Fork with port publish

• crucible fork -p HOST:GUEST — publish a host port on a fork (docker run -p semantics for copies): fork a running server onto its own port. The fork API takes an optional JSON body ({count, publish}); publishing requires count 1 since host ports are exclusive. Go SDK Fork gained variadic publish mappings (source-compatible).

The SDK foundation

The typed client became a public, dependency-free Go module, and the whole REST contract now fans out from one drift-guarded OpenAPI spec.

• Public Go SDK — github.com/gnana997/crucible/sdk, versioned independently as sdk/vX.Y.Z: package crucible (client + handles), sdk/api (DTOs), sdk/wire (frame codec). Typed errors, Page[T] lists, SDK-owned Identity. The CLI/TUI/MCP now run on it.
• Interactive exec over WebSocket — GET /sandboxes/{id}/exec + upgrade: the cross-language transport (fetch-style stacks can't speak the hijacked stream). Same frame protocol either way.
• The wire protocol, specified — wire.md plus recorded conformance fixtures, so an SDK codec in any language is buildable and testable with no daemon and no KVM. Generated TypeScript + Python types from the spec, with a CI drift guard.

Drop your code in and run it

• crucible cp — push a local file or directory into a running sandbox as a tar stream (no image build, no Dockerfile), path-escape safe. Plus MCP write_files / read_file.
• TUI live logs view, one-command Linux install that provisions the guest kernel, and a mirrored vmlinux release asset.

The safe docker run + cross-platform client

• OCI image boot — crucible run <image> boots an unmodified image's entrypoint in a microVM; crucible build converts a Dockerfile (daemon stays Docker-free); publish host ports with -p.
• Interactive shell (crucible shell, no PTY), --disk sizing, top-level stop/rm, durable logs, an MCP server, and scoped/policy API-key auth.
• The CLI, TUI, and mcp serve cross-compile to macOS and Windows and drive a remote Linux daemon; a reworked one-line installer for the daemon and client-only installs.

The core runtime

Firecracker microVMs under jailer, snapshot & fork with lazy userfaultfd memory, clone-safety (per-fork RNG reseed + machine-identifier rotation), per-sandbox networking (netns / veth / nftables / DHCP / DNS proxy) with default-deny egress, cgroup v2 quotas, a durable reconciled registry, a Prometheus /metrics endpoint, and native rootfs profiles.

See CHANGELOG.md for the full per-release detail.