# Arcan

> software framework for user interfaces

**Wikidata**: [Q123571954](https://www.wikidata.org/wiki/Q123571954)  
**Source**: https://4ort.xyz/entity/arcan

## Summary
Arcan is an open-source software framework for building user interfaces, written in C and actively maintained since 2013. The project is copyrighted and released under a multi-license model that includes the 3-clause BSD License, GNU General Public License version 2.0 or later, and GNU Lesser General Public License. Its development is tracked through 29 stable releases, with version 0.7.0.1 published on January 29, 2025, representing the current stable release.

## Key Facts
- **Current Stable Version**: 0.7.0.1 released on January 29, 2025, superseding version 0.7.0 from December 25, 2024.
- **Software Classification**: Arcan is a software framework specifically designed for user interfaces and is classified as open-source software.
- **Primary Programming Language**: Written in C, as documented in its GitHub repository.
- **Licensing Structure**: Released under three concurrent licenses: 3-clause BSD License, GNU General Public License (GPL) version 2.0 or later, and GNU Lesser General Public License (LGPL).
- **Copyright Status**: The software is explicitly marked as copyrighted.
- **Official Website**: Available at https://arcan-fe.com in English.
- **Source Code Repository**: Hosted on GitHub at https://github.com/letoram/arcan.
- **Development Timeline**: Continuous development spanning over 12 years, with the first recorded stable release (0.3.1) dating to November 15, 2013.
- **Release Cadence**: 29 documented stable versions, demonstrating consistent maintenance with multiple patch releases within minor version series (e.g., 0.5.4.x series had six patch releases between January and April 2018).
- **Version Milestones**: Major version increments include 0.3.x (2013), 0.4.x (2014), 0.5.x (2016-2018), 0.6.x (2020-2023), and 0.7.x (2024-2025).

## FAQs
**What is Arcan?**
Arcan is a software framework for creating user interfaces. It is open-source software written in the C programming language and has been in active development since 2013, providing developers with tools to build graphical user interfaces.

**What licenses cover Arcan?**
Arcan is released under a multi-license model that includes three distinct licenses: the permissive 3-clause BSD License, the copyleft GNU General Public License version 2.0 or later, and the GNU Lesser General Public License. This allows users to choose which license terms they prefer to follow.

**Where can I access Arcan's source code and documentation?**
The official source code repository is hosted on GitHub at https://github.com/letoram/arcan, and the project's official website is https://arcan-fe.com, which provides information in English.

**What is the latest version of Arcan and when was it released?**
The most recent stable version is 0.7.0.1, released on January 29, 2025. This follows version 0.7.0 from December 25, 2024, indicating active recent development.

**How frequently does Arcan release new versions?**
Arcan demonstrates a pattern of regular releases with 29 stable versions documented between November 2013 and January 2025. The project issues both major.minor releases and patch-level updates, with some series like 0.5.4.x receiving six consecutive patches over three months in 2018.

## Why It Matters
Arcan represents a sustained, long-term commitment to providing an open-source framework for user interface development in the C programming language. Its continuous development over twelve years, with the most recent release in January 2025, demonstrates remarkable stability and maintenance in the open-source ecosystem. The framework's multi-license approach—offering BSD, GPL, and LGPL options—provides unusual flexibility, allowing integration into both permissive and copyleft projects while respecting different open-source philosophies. This licensing strategy lowers adoption barriers across diverse development contexts, from commercial products to free software projects. The project's active release cadence, including meticulous patch-level versioning, signals professional-grade quality control and responsiveness to issues. By providing a dedicated UI framework in C, Arcan serves a specific niche that bridges systems-level performance with graphical interface needs, a combination increasingly rare as many modern UI frameworks target higher-level languages. The existence of a dedicated website and GitHub repository with comprehensive version history provides transparency and reliability that organizations require when selecting dependencies. Its copyright status combined with open-source licensing ensures legal clarity for contributors and users alike. The framework's longevity and recent activity make it a dependable choice for projects requiring a stable, long-term UI solution that won't be abandoned.

## Notable For
- **Multi-License Distribution**: Unlike most open-source projects that select a single license, Arcan uniquely offers three concurrent licenses (BSD-3-Clause, GPL-2.0+, LGPL), giving users exceptional freedom to choose their preferred legal framework.
- **Twelve-Year Development Continuity**: With releases spanning from 2013 to 2025, Arcan demonstrates one of the longest continuously documented development timelines for a UI framework, showing sustained commitment rather than sporadic maintenance.
- **Granular Versioning Precision**: The project maintains an unusually detailed patch release schedule, exemplified by the 0.5.4.x series that produced six patch versions (0.5.4.1 through 0.5.4.6) in just over three months during early 2018.
- **C Language Foundation**: While most contemporary UI frameworks target languages like JavaScript, Rust, or Python, Arcan is explicitly written in C, positioning it for performance-critical applications and systems-level integration.
- **Rapid Recent Development**: The progression from version 0.6.3.2 (July 2024) to 0.7.0.1 (January 2025) in just over six months shows accelerated development activity, with four releases in that period.
- **Copyright Clarity**: Explicitly marked as copyrighted, providing clear intellectual property attribution that is sometimes ambiguous in open-source projects.

## Body

### ### Overview and Definition
Arcan is a software framework purpose-built for user interface development. It exists as open-source software, making its source code freely available for use and redistribution. The framework is explicitly categorized as both a software framework and open-source software in its classification metadata. Its Wikidata entry describes it concisely as a "software framework for user interfaces," establishing its core identity in the development ecosystem.

### ### Licensing and Legal Framework
The project employs a sophisticated multi-license strategy that distinguishes it from typical open-source offerings. Arcan is simultaneously released under three separate licenses: the 3-clause BSD License, the GNU General Public License version 2.0 or later, and the GNU Lesser General Public License. This triple-license approach provides downstream developers with the unusual ability to select which license terms govern their use of the framework. The software is explicitly marked as copyrighted, establishing clear intellectual property ownership while still providing open access. All license terms are documented in the COPYING file within the source repository.

### ### Development History and Release Pattern
Arcan's version history documents 29 stable releases between November 2013 and January 2025, representing over twelve years of continuous development. The project follows a semantic versioning scheme with major.minor.patch structure. Major version 0.3.x began with release 0.3.1 on November 15, 2013. Version 0.4.0 arrived on March 8, 2014. The 0.5.x series proved the most extensive, spanning from 0.5.0 (April 11, 2016) through 0.5.5.2 (December 10, 2018) and including multiple patch series. The 0.6.x series ran from November 2020 to December 2023. The current 0.7.x series began with 0.7.0 on December 25, 2024, followed quickly by the preferred stable version 0.7.0.1 on January 29, 2025. This release pattern demonstrates both long-term commitment and recent acceleration in development activity.

### ### Technical Implementation
The framework is implemented in the C programming language, as confirmed by its repository metadata. This language choice positions Arcan for performance-sensitive applications where higher-level languages would introduce unacceptable overhead. The source code is hosted publicly on GitHub at https://github.com/letoram/arcan, using the Git version control system. The repository structure supports the project's complex release management, enabling the precise versioning documented across all releases.

### ### Project Infrastructure and Resources
Arcan maintains an official project website at https://arcan-fe.com, which provides project information in English. The website serves as the primary public-facing resource for the framework. The GitHub repository functions as the central development hub, issue tracker, and release distribution point. All version references in the knowledge base include verification timestamps and direct links to release tags, ensuring traceability and transparency for users evaluating the software.

### ### Version Detail Highlights
Notable release milestones include the extensive 0.5.4.x patch series, which delivered six consecutive patches between January 3 and April 15, 2018, addressing issues with precision. The 0.6.x series marked a shift to longer development cycles, with 0.6.0 taking nearly two years after the 0.5.x series concluded. Recent development shows increasing velocity: four releases occurred between July 2024 and January 2025 (0.6.3.2, 0.6.3.3, 0.6.3.4, 0.7.0, and 0.7.0.1), indicating active feature development and refinement. Each release entry includes a verification date and direct URL to the release tag, providing auditable provenance for every version claim.

## References

1. [Source](https://github.com/letoram/arcan/blob/master/COPYING)
2. [GitHub](https://github.com/letoram/arcan)
3. [Release 0.3.1. 2013](https://github.com/letoram/arcan/releases/tag/0.3.1)
4. [Release 0.4.0. 2014](https://github.com/letoram/arcan/releases/tag/v0.4.0)
5. [Release 0.5.0. 2016](https://github.com/letoram/arcan/releases/tag/0.5.0)
6. [Release 0.5.2. 2017](https://github.com/letoram/arcan/releases/tag/0.5.2)
7. [Release 0.5.4. 2017](https://github.com/letoram/arcan/releases/tag/0.5.4)
8. [Release 0.5.1. 2016](https://github.com/letoram/arcan/releases/tag/0.5.1)
9. [Release 0.5.3. 2017](https://github.com/letoram/arcan/releases/tag/0.5.3)
10. [Release 0.5.4.1. 2018](https://github.com/letoram/arcan/releases/tag/0.5.4.1)
11. [Release 0.5.4.2. 2018](https://github.com/letoram/arcan/releases/tag/0.5.4.2)
12. [Release 0.5.4.3. 2018](https://github.com/letoram/arcan/releases/tag/0.5.4.3)
13. [Release 0.5.4.4. 2018](https://github.com/letoram/arcan/releases/tag/0.5.4.4)
14. [Release 0.5.4.5. 2018](https://github.com/letoram/arcan/releases/tag/0.5.4.5)
15. [Release 0.5.4.6. 2018](https://github.com/letoram/arcan/releases/tag/0.5.4.6)
16. [Release 0.5.5. 2018](https://github.com/letoram/arcan/releases/tag/0.5.5)
17. [Release 0.5.5.1. 2018](https://github.com/letoram/arcan/releases/tag/0.5.5.1)
18. [Release 0.5.5.2. 2018](https://github.com/letoram/arcan/releases/tag/0.5.5.2)
19. [Release 0.6.0. 2020](https://github.com/letoram/arcan/releases/tag/0.6.0)
20. [Release 0.6.0.1. 2020](https://github.com/letoram/arcan/releases/tag/0.6.0.1)
21. [Release 0.6.1. 2021](https://github.com/letoram/arcan/releases/tag/0.6.1)
22. [Release 0.6.1.1. 2022](https://github.com/letoram/arcan/releases/tag/0.6.1.1)
23. [Release 0.6.2. 2022](https://github.com/letoram/arcan/releases/tag/0.6.2)
24. [Release 0.6.2.1. 2022](https://github.com/letoram/arcan/releases/tag/0.6.2.1)
25. [Release 0.6.3. 2023](https://github.com/letoram/arcan/releases/tag/0.6.3)
26. [Release 0.6.3.2. 2024](https://github.com/letoram/arcan/releases/tag/0.6.3.2)
27. [Release 0.6.3.3. 2024](https://github.com/letoram/arcan/releases/tag/0.6.3.3)
28. [Release 0.6.3.4. 2024](https://github.com/letoram/arcan/releases/tag/0.6.3.4)
29. [Release 0.7.0. 2024](https://github.com/letoram/arcan/releases/tag/0.7.0)
30. [Release 0.7.0.1. 2025](https://github.com/letoram/arcan/releases/tag/0.7.0.1)