Live now · PR bot · Claude Code & Cursor

Every line knows why it exists. No blame. Just context. 

Synapse is your team's memory, for humans and AI agents. It knows why code is the way it is, tells your AI exactly what to touch before it codes, and catches what it broke after. Knowledge that never leaves.

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Works with GitHub · Claude Code · Cursor · Your code never trains models

QUESTIONS TEAMS ASK SYNAPSE

Why is this retry guarded by a lock?Who knows the payments module best?What breaks if I rename this column?Which services call the billing API?Where is rate limiting configured?Why does checkout retry twice?Why is this retry guarded by a lock?Who knows the payments module best?What breaks if I rename this column?Which services call the billing API?Where is rate limiting configured?Why does checkout retry twice?
What does this webhook do on uninstall?Does this function already exist?Where do we validate invitation tokens?Who owns the payments module?Which code has zero callers?How is a workspace kept isolated?What does this webhook do on uninstall?Does this function already exist?Where do we validate invitation tokens?Who owns the payments module?Which code has zero callers?How is a workspace kept isolated?

HOW IT WORKS

From repository to cited context in three steps.

01

Connect GitHub

Install the Synapse GitHub App and choose exactly which repositories it can see. It never writes to your code.

synapse-apiconnected
synapse-webconnected
02

We map the code

Every module, route, function and data model becomes a node in a graph that refreshes on each push.

modules
0
routes
0
models
0
03

Get the why, everywhere

In every file, on every pull request, and inside Claude Code or Cursor. Every answer links to the files and lines behind it.

1auth/auth.service.tsL128–139

PRODUCT

Context your team usually keeps in its head.

Every line knows why

LIVE

Decisions from pull requests, reviews and reverts, linked to the exact lines they explain. Every answer cites a file and a line range; when there's no evidence, Synapse says so instead of guessing.

apps/api/src/modules/auth/auth.service.tscited · L133–134
128if (session.revokedAt) {
129 const recentlyRotated =
130 session.replacedById !== null &&
131 now.getTime() - session.revokedAt.getTime() < REFRESH_REUSE_GRACE_MS;
132
133 if (!recentlyRotated) {
134 await this.revokeFamily(session.familyId, now);
135 this.logger.warn(…);
138 }
139 throw new UnauthorizedException('Refresh token has been revoked.');

Know what breaks

LIVE

Every caller of a file or function, straight from the code graph. Rebuilt on every push, never hand-drawn, never stale.

token.service.ts · hashToken() · 3 callers
auth.controller.tsL42
session.guard.tsL18
invitations.service.tsL77

Guardrails for AI agents

LIVE

Connect Claude Code or Cursor over MCP in one command. Before your agent writes code, it gets the exact files and lines to touch, functions to reuse, and past decisions not to break.

plan_changewhyblast_radiusfind_existing

Every PR, checked

LIVE

One comment on every pull request: risk, blast radius, duplicate and dead code, API calls in loops, and the past decisions it touches. Ship small, ship safe.

Knowledge that never leaves

When someone moves on, their reasoning stays. New engineers get each file's story on day one. No blame, just context.

SECURITY

Built for code you can't afford to leak.

Read-only on your code

The GitHub App reads contents and metadata. Its only write is one comment per pull request, which you can turn off. It can never push, merge or change settings.

Never used for training

Your code is not used to train models, and never passes through free-tier AI APIs.

Isolated per workspace

Every query is scoped to one workspace. Outsiders get a 404 — not even a hint a resource exists.

Verified events

Every GitHub webhook is HMAC-verified and processed exactly once.

Ship with context, not guesswork.

Live today. We're onboarding a small group of engineering teams as design partners: free for three months, and you shape the roadmap.