Waleed
fcdcaed00d
* fix(memory): add Bun.gc, stream cancellation, and unconsumed fetch drains * fix(memory): await reader.cancel() and use non-blocking Bun.gc * fix(memory): update Bun.gc comment to match non-blocking call * fix(memory): use response.body.cancel() instead of response.text() for drains * fix(executor): flush TextDecoder after streaming loop for multi-byte chars * fix(memory): use text() drain for SecureFetchResponse which lacks body property * fix(chat): prevent premature isExecuting=false from killing chat stream The onExecutionCompleted/Error/Cancelled callbacks were setting isExecuting=false as soon as the server-side SSE stream completed. For chat executions, this triggered a useEffect in chat.tsx that cancelled the client-side stream reader before it finished consuming buffered data — causing empty or partial chat responses. Skip the isExecuting=false in these callbacks for chat executions since the chat's own finally block handles cleanup after the stream is fully consumed. * fix(chat): remove useEffect anti-pattern that killed chat stream on state change The effect reacted to isExecuting becoming false to clean up streams, but this is an anti-pattern per React guidelines — using state changes as a proxy for events. All cleanup cases are already handled by proper event paths: stream done (processStreamingResponse), user cancel (handleStopStreaming), component unmount (cleanup effect), and abort/error (catch block). * fix(servicenow): remove invalid string comparison on numeric offset param * upgrade turborepo
Build and deploy AI agent workflows in minutes.
Build Workflows with Ease
Design agent workflows visually on a canvas—connect agents, tools, and blocks, then run them instantly.
Supercharge with Copilot
Leverage Copilot to generate nodes, fix errors, and iterate on flows directly from natural language.
Integrate Vector Databases
Upload documents to a vector store and let agents answer questions grounded in your specific content.
Quickstart
Cloud-hosted: sim.ai
Self-hosted: NPM Package
npx simstudio
Note
Docker must be installed and running on your machine.
Options
| Flag | Description |
|---|---|
-p, --port <port> |
Port to run Sim on (default 3000) |
--no-pull |
Skip pulling latest Docker images |
Self-hosted: Docker Compose
git clone https://github.com/simstudioai/sim.git && cd sim
docker compose -f docker-compose.prod.yml up -d
Using Local Models with Ollama
Run Sim with local AI models using Ollama - no external APIs required:
# Start with GPU support (automatically downloads gemma3:4b model)
docker compose -f docker-compose.ollama.yml --profile setup up -d
# For CPU-only systems:
docker compose -f docker-compose.ollama.yml --profile cpu --profile setup up -d
Wait for the model to download, then visit http://localhost:3000. Add more models with:
docker compose -f docker-compose.ollama.yml exec ollama ollama pull llama3.1:8b
Using an External Ollama Instance
If Ollama is running on your host machine, use host.docker.internal instead of localhost:
OLLAMA_URL=http://host.docker.internal:11434 docker compose -f docker-compose.prod.yml up -d
On Linux, use your host's IP address or add extra_hosts: ["host.docker.internal:host-gateway"] to the compose file.
Using vLLM
Sim supports vLLM for self-hosted models. Set VLLM_BASE_URL and optionally VLLM_API_KEY in your environment.
Self-hosted: Dev Containers
- Open VS Code with the Remote - Containers extension
- Open the project and click "Reopen in Container" when prompted
- Run
bun run dev:fullin the terminal or use thesim-startalias- This starts both the main application and the realtime socket server
Self-hosted: Manual Setup
Requirements: Bun, Node.js v20+, PostgreSQL 12+ with pgvector
- Clone and install:
git clone https://github.com/simstudioai/sim.git
cd sim
bun install
- Set up PostgreSQL with pgvector:
docker run --name simstudio-db -e POSTGRES_PASSWORD=your_password -e POSTGRES_DB=simstudio -p 5432:5432 -d pgvector/pgvector:pg17
Or install manually via the pgvector guide.
- Configure environment:
cp apps/sim/.env.example apps/sim/.env
cp packages/db/.env.example packages/db/.env
# Edit both .env files to set DATABASE_URL="postgresql://postgres:your_password@localhost:5432/simstudio"
- Run migrations:
cd packages/db && bunx drizzle-kit migrate --config=./drizzle.config.ts
- Start development servers:
bun run dev:full # Starts both Next.js app and realtime socket server
Or run separately: bun run dev (Next.js) and cd apps/sim && bun run dev:sockets (realtime).
Copilot API Keys
Copilot is a Sim-managed service. To use Copilot on a self-hosted instance:
- Go to https://sim.ai → Settings → Copilot and generate a Copilot API key
- Set
COPILOT_API_KEYenvironment variable in your self-hosted apps/sim/.env file to that value
Environment Variables
Key environment variables for self-hosted deployments. See .env.example for defaults or env.ts for the full list.
| Variable | Required | Description |
|---|---|---|
DATABASE_URL |
Yes | PostgreSQL connection string with pgvector |
BETTER_AUTH_SECRET |
Yes | Auth secret (openssl rand -hex 32) |
BETTER_AUTH_URL |
Yes | Your app URL (e.g., http://localhost:3000) |
NEXT_PUBLIC_APP_URL |
Yes | Public app URL (same as above) |
ENCRYPTION_KEY |
Yes | Encrypts environment variables (openssl rand -hex 32) |
INTERNAL_API_SECRET |
Yes | Encrypts internal API routes (openssl rand -hex 32) |
API_ENCRYPTION_KEY |
Yes | Encrypts API keys (openssl rand -hex 32) |
COPILOT_API_KEY |
No | API key from sim.ai for Copilot features |
Tech Stack
- Framework: Next.js (App Router)
- Runtime: Bun
- Database: PostgreSQL with Drizzle ORM
- Authentication: Better Auth
- UI: Shadcn, Tailwind CSS
- State Management: Zustand
- Flow Editor: ReactFlow
- Docs: Fumadocs
- Monorepo: Turborepo
- Realtime: Socket.io
- Background Jobs: Trigger.dev
- Remote Code Execution: E2B
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.
Made with ❤️ by the Sim Team