astrona-io/codesynapse

CodeSynapse indexes a repository into a graph and answers small, precise questions from it, so your coding agent asks the graph instead of opening whole files.
Ask for ReplaceRepo and you get its signature, location, 3 callers, the 2 tests that reach it and the doc section that describes it, in a few hundred tokens. On this repository that cuts the context an agent needs per question by a median 92% (codesynapse stats).
Indexes Go (type-checked, exact calls and interface dispatch), Python, JavaScript, TypeScript, Vue, Java, Kotlin, Rust, C#, PHP, Ruby, Markdown, YAML, Helm charts, git history and dependencies with their CVEs.
Serves agents over MCP, people through a web dashboard, and CI through a CLI.
Reviews security (graded A–F, with reachability), licences, unused code, duplicates and the impact of a diff.
Runs on NebulaGraph and Milvus, all Apache-2.0, on your own machine or cluster.
## Quick start
You need just and Docker or Podman.
sh
just up # writes .env with random secrets, builds and starts everything
open http://localhost:3000 # dashboard: sign in as admin (password in .env), replace it, create your organisation
just ingest ~/src/my-service # indexes a checkout (needs a git origin remote)
just ingest indexes the checkout through the worker, named after its origin remote. To see it in your organisation, sign in as an owner, open Repositories, choose Add and paste the origin's address: the dashboard links the index instead of cloning (a private repository needs your organisation's Git token). Repositories you add by URL are cloned and indexed by the worker without just ingest.
Then connect your agent. For Claude Code: sign in, create a key under Settings → API keys, and run
sh
CODESYNAPSEMCPTOKEN= just mcp
Other clients and the session contract: Agent context. What to ask once connected: Agent guide.
## CLI
No server needed for the offline commands:
sh
brew install astrona-io/tap/codesynapse
# or: go install github.com/astrona-io/codesynapse/cmd/codesynapse@latest
codesynapse audit . # security review
codesynapse audit . --fail-on high # CI gate
codesynapse audit . --changed --fail-on high # pre-commit: staged files only
codesynapse licenses . # dependency licences
codesynapse cleanup . # unused code, files, modules
codesynapse upgrade-impact golang.org/x/net@v0.40.0 # what a Go module upgrade changes for you
codesynapse review . --base origin/main --offline # impact of the current branch
codesynapse review . --offline --fail-on-new high # CI gate on what the branch adds
## GitHub Action
Review every pull request: changed symbols and their impact, the tests to run, and the security findings the change introduces and fixes, posted as one comment that updates on each push.
yaml
on: pullrequest
permissions:
contents: read
pull-requests: write
jobs:
codesynapse:
runs-on: ubuntu-latest
steps:
uses: actions/checkout@v7
with:
fetch-depth: 0
uses: astrona-io/codesynapse@vX.Y.Z # a release tag, or its commit SHA
with:
fail-on-new: high # fail on new high or critical findings only