Sim: Open-Source Agentic Workflow Builder

Published:Dec 11, 2025 17:20
1 min read
Hacker News

Analysis

Sim is presented as an open-source alternative to n8n, focusing on building agentic workflows with a visual editor. The project emphasizes granular control, easy observability, and local execution without restrictions. The article highlights key features like a drag-and-drop canvas, a wide range of integrations (138 blocks), tool calling, agent memory, trace spans, native RAG, workflow versioning, and human-in-the-loop support. The motivation stems from the challenges faced with code-first frameworks and existing workflow platforms, aiming for a more streamlined and debuggable solution.

Reference

The article quotes the creator's experience with debugging agents in production and the desire for granular control and easy observability.