Sim (originally launched as Sim Studio) is an open-source AI workspace for building, deploying and managing AI agents. Users compose agent logic in a drag-and-drop visual builder, describe workflows in plain English, or write code; workflows can be deployed as a chat interface or an API. The platform bundles knowledge bases for semantic memory, structured tables, a shared file store, and run-level logs that trace each block execution with real cost attribution. It connects to more than 1,000 integrations including Slack, HubSpot, Salesforce, Notion, GitHub, Gmail, Jira, Linear, Supabase and Stripe, and supports OpenAI, Anthropic, Google, DeepSeek and xAI models. Sim is SOC 2 compliant and offers self-hosting. The company states over 100,000 builders use the product and its GitHub repository has roughly 29,000 stars.
Funding
Sim raised a $7M Series A led by Standard Capital, announced on 12 November 2025. The company was part of Y Combinator's Spring 2025 (X25) batch.