What is the main difference between Keycloak and Stack Auth?

Keycloak and Stack Auth are both authentication & sso providers but differ in their approach, features, and target audience. Compare their GitHub stats, technology stack, and community adoption to make the best choice.

Which is better: Keycloak or Stack Auth?

The choice between Keycloak and Stack Auth depends on your specific needs, technical requirements, and team preferences. Both are quality open source solutions with active communities.

Can I migrate from Keycloak to Stack Auth?

Migration between Keycloak and Stack Auth is possible but requires careful planning. Consider data export/import capabilities, feature parity, and potential workflow changes.

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Keycloak vs Stack Auth

Learn how Keycloak and Stack Auth differ in their key features, development activity, technology stack and community adoption, so you can decide which of these authentication & sso providers is best for you.

Keycloak

Comprehensive open source identity management solution offering single sign-on, social login, and fine-grained authorization for applications and services.

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Stars
34,047
Forks
8,273
Last commit
14 hours ago
Repository age
13 years
License
Apache-2.0

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Auto-fetched 39 minutes ago.

Stack Auth

Stack Auth provides secure authentication, authorization, and user management for developers in just 5 minutes.

Visit Stack Auth Read more

Stars
6,770
Forks
513
Last commit
13 hours ago
Repository age
2 years
Self-hosted
Yes

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Auto-fetched 40 minutes ago.

Detailed Comparison

Keycloak appears to have several advantages over Stack Auth, particularly in popularity, maturity and licensing. Consider your specific needs regarding popularity, activity, technology, maturity, licensing and features when making your decision.

Keycloak wins

Community & Popularity

Keycloak significantly outpaces Stack Auth in community adoption with 34,047 stars compared to 6,770 stars on GitHub. This 5.0x difference suggests Keycloak has a much larger and more active community. In terms of developer contributions, Keycloak has 8,273 forks, indicating strong developer engagement.

Comparable

Development Activity

Both projects show recent activity, with Keycloak last updated 14 hours ago and Stack Auth 13 hours ago.

Comparable

Technology Stack

Both tools share common technology foundations, being built with JavaScript, CSS, Bash, Typescript, JSX. However, they differ in their additional technology choices: Keycloak uses Python, C, Java while Stack Auth leverages Next.js.

Keycloak wins

Project Maturity

Keycloak has been in development longer, starting 13 years ago, compared to Stack Auth which began 2 years ago. This 10.8-year head start suggests Keycloak may have more mature features and established processes.

Keycloak wins

Licensing

Keycloak is licensed under Apache-2.0, while Stack Auth's license terms are not publicly specified.

Comparable

Use Cases & Features

Both tools serve similar use cases in Authentication & SSO, Authorization & Permissions.

Stack Auth wins

Hosting & Deployment

Stack Auth provides self-hosting options for complete data control and customization, while Keycloak may be primarily cloud-based or require different deployment approaches.