The idea

“Sim – Apache-2.0 n8n alternative https://github.com/simstudioai/sim Founder's Show HN post: Hey HN, Waleed here. We're building Sim (https://sim.ai/), an open-source visual editor to build agentic workflows. Repo here: https://github.com/simstudioai/sim/. Docs here: https://docs.sim.ai. You can run Sim locally using Docker, with no execution limits or other restrictions. We started building Sim almost a year ago after repeatedly troubleshooting why our agents failed in production. Code-first frameworks felt hard to debug because of implicit control flow, and workflow platforms added more overhead than they removed. We wanted granular control and easy observability without piecing everything together ourselves. We launched Sim [1][2] as a drag-and-drop canvas around 6 months ago. Since then, we've added: - 138 blocks: Slack, GitHub, Linear, Notion, Supabase, SSH, TTS, SFTP, MongoDB, S3, Pinecone, ... - Tool calling with granular control: forced, auto - Agent memory: conversation memory with sliding window support (by last n messages or tokens) - Trace spans: detailed logging and observability for nested workflows and tool calling - Native RAG: upload documents, we chunk, embed with pgvector, and expose vector search to agents - Workflow deployment versioning with rollbacks - MCP support, Human-in-the-loop block - Copilot to build workflows using natural language (just shipped a new version that also acts as a superagent and can call into any of your connected services directly, not just build workflows) Under the hood, the workflow is a DAG with concurrent execution by default. Nodes run as soon as their dependencies (upstream blocks) are satisfied. Loops (for, forEach, while, do-while) and parallel fan-out/join are also first-class primitives. Agent blocks are pass-through to the provider. You pick your model (OpenAI, Anthropic, Gemini, Ollama, vLLM), and and we pass through prompts, tools, and response format directly to the provider API. We normalize response shapes for block interoperability, but we're not adding layers that obscure what's Landing page content (simstudioai/sim): # simstudioai/sim Sim is the collaborative workspace to build, deploy, and monitor AI agents and workflows. Used by 100,000+ builders. - Stars: 29478 - Forks: 3796 - Watchers: 29478 - Open issues: 303 - License: Apache License 2.0 - Homepage: https://www.sim.ai - Default branch: main - Created: 2025-01-05T22:47:49Z ## Languages - CSS - Dockerfile - Go Template - HTML - JavaScript - MDX - Objective-C++ - PLpgSQL - Python - Shell - TypeScript ## Topics - agent-workflow - agentic-workflow - agents - ai - aiagents - anthropic - artificial-intelligence - automation - chatbot - deepseek - gemini - low-code - nextjs - no-code - openai - rag - react - typescript ## Top Contributors - waleedlatif1 (3893 contributions) - icecrasher321 (987 contributions) - emir-karabeg (685 contributions) - TheodoreSpeaks (424 contributions) - Sg312 (335 contributions) - aadamgough (99 contributions) - j15z (53 contributions) - BillLeoutsakosvl346 (38 contributions) - dependabot[bot] (13 contributions) - adithyaakrishna (12 contributions) --- ## README A workspace to build, deploy and manage AI agents and workflows. ## Quickstart ### Cloud-hosted: sim.ai ### Self-hosted ```bash npx sim-setup ``` Open http://localhost:3000 ## 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: ```bash npx sim-setup config npx sim-setup add email npx sim-setup ad”