The hosted `<PublicEnvScript>` rendered a plain `<script>`, which lands at the end of `<head>` — after the ~40 `<script async>` chunk tags Next emits at the top of the document. An async script runs as soon as its fetch resolves, so on a warm cache a Next chunk could execute (and hydration begin) before the parser reached the env tag, leaving `window.__ENV` undefined for the first render. That surfaced as "Something went wrong" on the workflow page, since `getBaseUrl()` throws during the deploy modal's render, and as the socket falling back to the page origin instead of NEXT_PUBLIC_SOCKET_URL. Regressed in #5522, which replaced next-runtime-env's PublicEnvScript (to avoid its unstable_noStore forcing dynamic rendering) with a static equivalent that dropped the beforeInteractive strategy. - render the library's own `<EnvScript>`, which defaults to beforeInteractive and does not call unstable_noStore — hosted and self-hosted now share one implementation and one loading strategy - drop the hand-rolled serialization and `<` escaping; Next's beforeInteractive path already runs the payload through htmlEscapeJsonString, which escapes `& > < U+2028 U+2029` - fall back to the browser origin in getBaseUrl() rather than throwing, so a missing injected env can never tear down a page through the error boundary; server-side callers still fail loudly - read NEXT_PUBLIC_EMAIL_PASSWORD_SIGNUP_ENABLED via getEnv() in the SSO form, matching login/signup/auth-modal — `env.X` returns the build-time placeholder, not the runtime value
A workspace to build, deploy and manage AI agents and workflows.
Quickstart
Cloud-hosted: sim.ai
Self-hosted
git clone https://github.com/simstudioai/sim.git && cd sim
bun run 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, knowledge, and scheduled tasks all live in the same workspace.
Tables — a database, built in |
Files — one store for your team and every agent |
Knowledge — your agents' memory |
Scheduled tasks — runs on your schedule |
Self-hosting
bun run setup is an interactive wizard: it provisions the database, generates secrets, writes your .env files, connects a Chat API key, and starts Sim the way you choose:
- Local dev — run from source to contribute or hack on Sim
- Docker Compose — a self-contained instance for testing self-hosting
- Kubernetes (Helm) — deploy to a local cluster
When it finishes, open http://localhost:3000.
Manage your install with bun run sim:
bun run sim start | stop | restart # bring your install up / down / cycle
bun run sim status # what's installed and healthy
bun run sim logs # follow logs
bun run sim doctor # diagnose configuration problems
bun run sim down # remove containers (data kept)
bun run sim reset # archive .env and wipe managed data
sim detects how you're running (Docker Compose, local dev, or Kubernetes) and acts accordingly.
Prefer a bare sim? Run bun link once — but note sim lands in ~/.bun/bin, which Homebrew's bun doesn't add to your PATH, so you may need export PATH="$HOME/.bun/bin:$PATH" in your shell profile.
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. bun run 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.





