* fix(auth): bound the three unbounded session-policy caches security-policy.ts and session-policy.ts are read from Better Auth's session create and update hooks, so they run on every session validation. All three caches were plain Maps with a hand-rolled 'Date.now() - fetchedAt < TTL' read and no ceiling: entries were released only by an explicit invalidate, so they grew for the life of the process. membershipCache is the sharpest of the three because it is keyed by user, not organization — one entry per user who ever authenticated on that instance. Move all three to LRUCache, already a direct dependency and the pattern copilot/entitlements.ts and providers/client-cache.ts use. The library owns the TTL and the ceiling; every existing invalidate* keeps working unchanged. Two things to preserve, both now pinned by tests: - membership results keep their asymmetric TTL (a non-member result expires far sooner, so a user who joins through a path this codebase never sees cannot dodge the new org's policy). Expressed as membershipCacheTtlMs rather than an inline ternary, since it is a security property and not a tuning knob. - reads test '!== undefined', because a version is a number and a membership is nullable — a truthiness check would treat both as a miss. security-policy.ts had no test file; adds one covering caching, invalidation, failure fallbacks and the TTL asymmetry. * fix(auth): raise the cache ceilings to a memory backstop getSessionCookieCacheVersion feeds Better Auth's session.cookieCache.version, so these are read on every session read, not just create/refresh. At max: 1000 a busy instance could exceed the live key set inside the 60s TTL and start evicting early — never a wrong answer (a miss is one indexed lookup, exactly the pre-cache behaviour) but a hit-rate cliff on a hot path. Entries are a few dozen bytes, so headroom is nearly free: orgs 1k -> 20k, users 10k -> 100k. That is single-digit MB at worst and puts the ceiling far above any plausible per-instance working set, leaving it as the memory backstop it was meant to be. * docs(rules): write down the caching decision tree The lifecycle-map-vs-TTL-cache distinction, the ceiling-as-backstop sizing, and the fetchMethod-unless-you-need-a-hang-deadline call each took real digging to settle. Recording them so the next cache does not re-derive the same answers — or re-introduce the unbounded tenant-keyed Map this branch just removed. Notes the two non-obvious traps behind that: ttl alone does not bound memory without a ceiling, and React cache() is a no-op in Trigger workers, so a gate that looks free on a settings page is uncached and per-block on the executor.
A workspace to build, deploy and manage AI agents and workflows.
Quickstart
Cloud-hosted: sim.ai
Self-hosted
npx sim-setup
Capabilities
- Connect 1,000+ integrations and every major LLM
- Add Slack, Notion, HubSpot, Salesforce, databases, and more
- Build agents visually, conversationally, or with code
- Ingest files, knowledge bases, and structured table data
- Monitor runs, logs, schedules, and workflow activity
One workspace, every surface
Chat and workflows are just the start — tables, files, and knowledge all live in the same workspace.
Tables — a database, built in |
Files — one store for your team and every agent |
Knowledge — your agents' memory |
Self-hosting
Requirements: Node.js 20+ and Docker.
npx sim-setup is an interactive wizard that creates a small sim/ deployment directory, provisions the database, generates secrets, writes .env, connects a Chat API key, and starts the published Sim images with Docker Compose. It does not clone the repository.
When it finishes, open http://localhost:3000.
Inside a cloned Sim repository, run bun run sim-setup to unlock the source-only local development and Kubernetes modes.
Reconfigure an optional capability without rerunning the full wizard:
npx sim-setup config
npx sim-setup add email
npx sim-setup add storage
npx sim-setup add sandbox
npx sim-setup add jobs
npx sim-setup add cache
npx sim-setup add knowledge
npx sim-setup add llm
npx sim-setup add integration slack
npx sim-setup config detects the effective local-dev, Docker Compose, or current-context
Helm configuration and reports configured, missing, or invalid capabilities and OAuth
integrations without printing credential values. This is separate from npx sim-setup status,
which reports whether installed services are running and healthy.
Manage your install from its directory:
npx sim-setup start | stop | restart # bring your install up / down / cycle
npx sim-setup update # pull and apply Compose images
npx sim-setup status # what's installed and healthy
npx sim-setup logs # follow logs
npx sim-setup doctor # diagnose configuration problems
npx sim-setup down # remove containers (data kept)
npx sim-setup reset # archive .env and wipe managed data
The setup package detects how you're running and acts accordingly. Use --dir <path> to create or manage a deployment somewhere other than ./sim.
Sim also supports local models via Ollama and vLLM. See the self-hosting docs for details.
Chat API Keys
Chat is a Sim-managed service. npx sim-setup connects a Chat API key for you — sign in when it opens your browser and the key is stored automatically. To view, create, or revoke keys later, go to sim.ai/selfhost/settings/chat-keys.
Environment Variables
See the environment variables reference for the full list, or apps/sim/.env.example for defaults.
Tech Stack
Next.js · Bun · PostgreSQL · Drizzle · Better Auth · Tailwind — and the rest of the stack
- Framework: Next.js (App Router)
- Runtime: Bun
- Database: PostgreSQL with Drizzle ORM
- Authentication: Better Auth
- Schema Validation: Zod
- UI: Shadcn, Tailwind CSS
- Streaming Markdown: Streamdown
- State Management: Zustand, TanStack Query
- Flow Editor: ReactFlow
- Docs: Fumadocs
- Monorepo: Turborepo
- Realtime: Socket.io
- Background Jobs: Trigger.dev
- Remote Code Execution: E2B
- Isolated Code Execution: isolated-vm
Contributing
We welcome contributions! Please see our Contributing Guide for details.
License
This project is licensed under the Apache License 2.0 - see the LICENSE file for details.




