Engine 0.19.0 — npx install, MCP registry, Node support

npx is now the shortest way in. Until this release the engine ran only from docker run or a repo clone. An MCP client config is now the whole install — and the safe default (reads allowed, writes and DDL denied, everything audited) needs nothing else.

{
  "mcpServers": {
    "midplane": {
      "command": "npx",
      "args": ["-y", "midplane", "server", "--stdio"],
      "env": { "DATABASE_URL": "postgres://user:pass@host:5432/db" }
    }
  }
}

Needs Node 22.16+ or 24+. See the standalone engine for the policy file, the audit log, and picking a least-privilege role.

What's new

The midplane npm package. A single ~80 KB bundle with no install scripts and no native modules. It's deliberately not minified — this is a security tool, and anyone evaluating what npx midplane does should be able to read the artifact — and its runtime dependencies stay external rather than vendored, so npm audit and Dependabot can still see them.

Listed in the official MCP registry as ai.midplane/midplane, under DNS-verified ownership of midplane.ai.

midplane server takes --stdio and --http, overriding MIDPLANE_TRANSPORT — a client config is a command line plus an env block, and the command comes first.

The engine runs on Node 22.16+ or 24+ as well as Bun 1.3+. The Docker image is unchanged, and both artifacts build from the same source at the same version.

DB_PATH defaults to ~/.midplane/audit.db outside a container (/data/audit.db inside one, unchanged). /data isn't writable on a developer's machine, so the old default made a local run fail at boot on the audit log. Read the log back with npx midplane audit denies.

Fixes

• midplane server could run every query twice when bundled. Two servers came up on one stdio pipe, each answering every request — correct-looking results, but two audit trails and two executions of every allowed write. There is now one entry point, and a smoke test asserts that one tool call produces exactly one query id.
• midplane query --stdio and doctor's stdio canary were broken in the compiled binary, which passed a virtual entry-script path to its own child process. Both work again.

A note on provenance

0.19.0 carries no npm provenance attestation; later releases do. Creating a package on npm requires setting its access, which a CI token may no longer do — so the publish that creates a package can't come from CI, and there was no CI identity to sign with. Every release after this one attests automatically over OIDC. Verify any release with npm view midplane dist.attestations.

Artifacts

Artifact	Transport
midplane@0.19.0 on npm	stdio
midplane/midplane:0.19.0 on Docker Hub and GHCR	Streamable HTTP
ai.midplane/midplane in the MCP registry	both

Full per-release detail is in engine/CHANGELOG.md. Docs: midplane.ai/docs.