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Open source · 12 languages · since 2005

All you ever need for your software architecture.

Construct, communicate and document. Proven and pragmatic. Takes the pain out of documentation.

Overview →

Quick download, English: AsciiDoc Markdown Word (.docx) All languages and formats →

Template

Drawers of a cabinet
The arc42 skeleton for architecture docs — you fill it with your decisions.

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Training

Participants in an arc42 training workshop
Mastering Software Architectures — prepares for the iSAQB Foundation certification.

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The method

To-do, doing, done slips of paper
Systematic but flexible — suits large and small teams, agile or not.

See the method

What is arc42?

arc42 is based on practical experience with many systems across domains — information and web systems, real-time and embedded, business intelligence and data warehouses. It gives you a template for the documentation and communication of software and system architecture.

  • Supports arbitrary technologies and tools — nothing to install.
  • Process-agnostic, and especially well-suited to lean and agile teams.
  • Open source and free of charge, in commercial and private settings — see the license.

There is plenty to learn from, too: browse our books, articles, talks and videos →.

Architecture trainings

Learn arc42 and modern software architecture straight from its creators — iSAQB-certified Foundation trainings, on-site and remote. Upcoming dates:

Hands-on architecture training — most classes taught by Peter Hruschka and Gernot Starke, the creators of arc42 (dates with other trainers say so):

Next dates

All courses and dates: trainings.arc42.org · as of 4 Aug 2026

See all dates & register → Training details

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