Introducing Celmis: self-hosted code intelligence over a symbol graph

Celmis is self-hosted code intelligence. It reads a set of repositories once and docker compose, with whichever model provider you This is the introduction — what it does, what it refuses to do, and how to run it. The I asked a question that spanned two repositories, and the answer quoted both. The question was ordinary: "How does the gateway talk to the payments service? Name the The answer found a Python publisher: def publish(self, batch_id: str, entries: dict[str, int]) -> None: """Emit one settlement event on the published topic.""" self.producer.send( SETTLEMENT_TOPIC, json.dumps({"batch_id": batch_id, "entries": entries}).encode(), ) and a TypeScript listener in a different repository: start(): void { this.bus.on(SETTLEMENT_TOPIC, (event) => { const payload = JSON.stringify({ type: "settlement", ...event }); for (const s of this.sockets) s.send(payload); }); } They never call each other. They meet on a Kafka topic. Then the answer added something Duplicated contract. The topic name (payments.settlement.v2) and the event payload src/config.py in payments and src/contract.ts in the gateway. Changing the topic name or the payload schema in one A reviewer that reads only the diff cannot say that. It never had the other repository Read the repositories once. Build a symbol graph — deterministically, with tree-sitter, Ask questions, answered with file:line citations, across repository and language boundaries. Review pull requests, with knowledge of who else calls the function in the diff — including from a repository not in the pull request. Audit dependencies, and produce the artefacts a buyer or an auditor asks for. Route what your running services are shouting about — alerts arrive, and the index already knows which repository the failing service is, and who owns it. Serve it over MCP, so your own editor or agent reads the same index under the same access rules. The index is the product. The rest are surfaces. On a real pull request in a demo repository, three findings, all on real lines: 6: const first = vals[0]; // vals is {} — undefined, not a TypeError 7: for (let i = 0; i <= vals.length; i++) // off by one 16: const n = parseInt(raw); // never throws, so the catch below is dead Three inline comments with suggestion blocks, one summary comment, zero false . I verified all three against the file in the PR branch by hand, Eighteen tools over the same index. Here is a real session, trimmed: --> initialize <-- 200 serverInfo: { "name": "celmis", "version": "1.29.1" } --> tools/list <-- 200 18 tools list_projects get_api_surface bootstrap_client search_symbols list_accessible_repos start_integration_walk find_consumers get_review route_incident get_owner get_review_policy get_dep_audit get_architecture list_deprecations list_dep_findings … --> tools/call search_symbols { "project_id": "083bd97a-…", "query": "SETTLEMENT_TOPIC" } <-- 200 { "matches": [ { "repo_slug": "…celmis-demo-gateway", "kind": "variable", "file": "src/contract.ts", "line": 2 }, { "repo_slug": "…celmis-demo-payments", "kind": "constant", "file": "src/config.py", "line": 9 } ], "count": 2 } One query. Two repositories, two languages, the same contract symbol — from a client that find_consumers is the one I use most: it answers This is the surface I nearly left out of this article, which was a mistake, because it is Your services are already producing alerts. They land in a channel where somebody has to So the same index answers it. An ingest endpoint takes the alert, a binding routes it, and POST /webhook/alerts/{token} { "severity": "critical", "repo_hint": "celmis-codereviewer/celmis-demo-gateway", "title": "checkout: unhandled exception in settle()" } → notif_delivered event=alert_received repo=celmis-codereviewer/celmis-demo-gateway severity=critical Review results ride the same rails — a finished pull-request review posts its own card: Review CHANGES · PR #4 — 0 critical · 3 error · 0 warn · 0 info. Two things worth stealing from how this is wired, both of which I got wrong first: The webhook signature is checked before anything else. Wrong signature → 401. 202. Replay the exact same delivery → {"status": "duplicate"} rather than a A failed channel test must not echo the URL it tested. Google Chat webhook URLs carry key and token in the query string — the URL is a credential. httpx puts the str(exc) verbatim, which meant a failed test handed the caller back the secret it was The dependency audit is the one part that is deterministic end to end — native A CycloneDX SBOM, and an evidence pack: sbom/<repo>.cdx.json CycloneDX, one per repository findings.json what was found against those components timeline.jsonl when each fact entered the record MANIFEST.json sha256 of every file above That last file is the point. An archive of files is not evidence — nothing in it stops a third : { "algorithm": "sha256", "files": { "findings.json": "921412d4bf97eb32fa4b3e8ad09447dab762f19d31ffec45bddb6d7962bf08e5", "sbom/gateway.cdx.json": "6eadeafad0043b85a51b65ddddba84ef7b43081064ed9e1b320c62838ddc3d8e", "timeline.jsonl": "b1815a8e3607712aa9332cd1f8d2d0ec6f93cd8dce53dd92844b8edcde790b3d" }, "generated_at": "2026-08-26T19:09:41Z" } Why now: from 11 September 2026, under the EU Cyber Resilience Act, manufacturers 24 hours. The SBOM itself is not mandated until December 2027 — which is the trap, The document is due in 2027. The visibility it describes is needed fifteen months earlier. The audit reports what it could not check, as prominently as what it found: Not fully checked (4). Treat a zero here as unknown, not as safe. - …demo-gateway — npm via npm-audit: no lock file (package-lock.json / pnpm-lock.yaml / yarn.lock) — cannot resolve the tree - …demo-gateway — all via osv-scanner: recognised no manifest or lock file here - …e2e-probe/requirements.txt — PyPI via pip-audit: dependency resolution failed — audited 4 pinned requirements directly, without the transitive tree An unchecked ecosystem reports zero vulnerabilities exactly like a clean one. If your is the finding. One machine. Postgres and Qdrant bundled — no external cluster to provision. git clone https://github.com/Celmis-labs/Celmis.git celmis cd celmis ./scripts/init-env.sh # generates .env, every secret in the format it needs docker compose --env-file .env up -d docker compose ps On a clean server that took 197 seconds from git clone to six healthy services — Bring your own model key: Gemini, Anthropic, OpenAI, OpenRouter, Groq or Mistral. A free No telemetry, no licence check — the only 17th of 50 on the Martian Code Review Bench offline set, stable under all three It measures one of the surfaces above — pull-request review on isolated I also audited every one of the 79 findings the benchmark counted against us. 33 were That audit is published in full, with Semantic search needs a generated vault. Until you make one, the UI says so in an orange banner rather than quietly returning worse answers. The execution sandbox has deliberate internet egress, because pip install and npm ci need it. No long-term support branch. Fixes land on the latest release. It does not make anyone compliant with anything, and it says so in its own output. Source, docs and the benchmark audit: https://celmis-labs.github.io Happy to answer anything — especially about the benchmark methodology, which is the part that deserves an argument.