Problem

Stack Auth addresses the tension between two unattractive choices in application identity. User authentication and authorization are mission-critical, so companies do not want their user data and login layer locked inside a proprietary vendor; yet building and maintaining production-grade auth on top of libraries is tedious as an application grows. The central pain is therefore greatest for developer-led startups and B2B software teams that need to ship login, signup, account management, organizations, permissions, and secure access controls quickly without creating a long-term infrastructure liability.

The killer use case is a B2B or Next.js application that needs more than basic authentication: customer organizations and teams, invitations, role-based access control, OAuth, password resets, account settings, and support tooling. Stack Auth is positioned to remove that recurring engineering work while preserving the option to control and export the underlying data, avoiding the switching costs associated with proprietary identity platforms.

Product / Service

Stack Auth is an open-source suite for authentication and user management that also covers authorization. It provides ready-made React components and customizable flows for sign-in, password resets, account settings, and teams; supports organizations, permissions and RBAC; handles OAuth and access tokens; offers webhooks, customizable emails, a user dashboard, and a REST API; and manages JWTs and access tokens so developers do not have to build that plumbing themselves. Teams can use headless SDKs or styled components, making the product useful both for rapid setup and for applications requiring a customized experience.

The delivery model combines self-hosting with managed cloud hosting. The original Stack Auth model offered a fully open-source, MIT/AGPL-licensed product that customers could run themselves or host with Stack, export their data from, and migrate away from without lock-in. Current pricing materials, presented under the Hexclave name, retain that model: self-hosting is free, while managed plans start free and scale through paid Team and Growth tiers, with support and service-level benefits at higher tiers.

Market

Stack Auth competes in developer-focused authentication, authorization, and user-infrastructure software. Its explicit alternatives include Auth0, which it characterizes as enterprise-oriented and more vendor-locked; Clerk, which is developer-friendly but proprietary; and open-source or adjacent options such as Supabase Auth, Auth.js/NextAuth, Ory, SuperTokens, and Keycloak. Its differentiation is the combination of polished developer experience, user-management and B2B authorization features, and genuine self-hostability rather than authentication alone or a proprietary hosted API.

The company entered Y Combinator's Summer 2024 batch and is listed as active; current repository materials identify the broader product as Hexclave and show approximately 6,825 GitHub stars and 521 forks, indicating meaningful open-source awareness and adoption. The evidence establishes community traction, a live hosted product, and published free and paid pricing, but does not establish a public customer count or revenue figure, so the most defensible characterization is an active, open-source developer-infrastructure company with commercial hosting ambitions rather than a business whose revenue scale is publicly documented.