Oso is a developer-focused authorization platform that provides tools and infrastructure for building and managing access control within software applications. The company's core product is an authorization-as-a-service solution that allows engineering teams to implement and enforce authorization logic — such as role-based access control (RBAC) and relationship-based access control (ReBAC) — without building these systems from scratch. Oso's platform is designed to be embedded directly into applications, enabling developers to define who can access what resources within their software. The company offers both a hosted cloud service and a local authorization option, the latter allowing authorization decisions to be made at the application layer without a network round-trip. A notable technical component is the use of a logic language for distributed SQL queries, enabling fine-grained data filtering based on authorization policies. The target market is primarily software engineering teams at companies that need to manage complex, scalable authorization requirements. Oso positions itself as an alternative to building custom in-house authorization systems, which it characterizes as a difficult and time-consuming problem. The company has also addressed the emerging challenge of AI coding agents holding API keys and credentials, partnering with Tailscale to improve security controls in agentic workflows. Oso is headquartered in New York City and has raised $25 million from investors including Sequoia, Felicis, and others.