Changelog

How to Read This Changelog

Entries are listed in reverse chronological order, with the most recent changes at the top. Each entry includes a date (or date range) and a description of what changed. Some entries affect a single page; others reflect broader structural or content updates that span multiple sections of the site.

This log is intended as a practical reference for anyone who wants to know what has changed and when. It may be useful for researchers citing specific editions or problem statements, as it records when corrections or clarifications were made. For a broader view of the competition's development over time, see the history page.

January 2026

20 January 2026 — Privacy Policy and Terms of Use Added

Added a formal privacy policy and terms of use page to the site. These pages document our data practices and the conditions governing use of site materials. The privacy policy includes GDPR-compliant language regarding data rights. Both pages are now linked from the site footer.

15 January 2026 — Refreshed Site Styling and Layout

Updated the site's visual presentation with improved typography, spacing, and responsive behaviour on smaller screens. Navigation was streamlined to improve access to frequently visited sections. The underlying content was not changed, but the reading experience should be noticeably improved across devices. Updated the FAQ page to reflect current practices.

8 January 2026 — Custom 404 Page

Added a custom not-found page with helpful navigation suggestions for visitors who reach a URL that does not correspond to an existing page. The page offers direct links to key sections of the site.

2025

September 2025 — Publication Records Updated

Updated the publications page with recently published workshop papers and technical reports that reference VSComp problems and solutions. Added bibliographic details for three new entries and corrected formatting issues in two existing citations.

April 2025 — Navigation Restructured

Reorganised the primary navigation to provide more direct access to the problems catalogue and solutions archive. The previous navigation grouped these under a single menu item; they are now top-level entries. Updated breadcrumb paths across all pages to reflect the new structure.

2024

November 2024 — Errata Corrections for 2014 Problem Set

Corrected two specification ambiguities in the 2014 problem set that had been identified by researchers working through the problems retrospectively. Added clarifying notes to the affected problem pages indicating the nature of the original ambiguity and the correction applied.

June 2024 — Solutions Archive Expanded

Added solution records for several submissions that were previously documented only in workshop proceedings. The solutions page now includes summary entries for these contributions, with references to the full papers where applicable.

February 2024 — About Page Revised

Revised the about page to better reflect the competition's current status and relationship to the broader formal-methods community. Updated descriptions of affiliated organisations and research groups.

2023

October 2023 — Contact Information Updated

Updated the contact page with current information for the organising committee. Removed references to email addresses that were no longer actively monitored.

March 2023 — Year Hub Pages Reformatted

Standardised the layout and content structure of all year hub pages. Each edition now follows a consistent format, with sections for overview, problems, results, and associated publications. This makes it easier to compare editions and find specific information.

2022

August 2022 — FAQ Section Expanded

Added several new entries to the FAQ page addressing questions about tool eligibility, team participation, and how to cite VSComp problems in academic work. Existing answers were reviewed for accuracy and clarity.

2021

December 2021 — Accessibility Improvements

Improved keyboard navigation and screen-reader compatibility across the site. Added ARIA labels to navigation elements, ensured proper heading hierarchy on all pages, and improved colour contrast in several areas to meet WCAG 2.1 AA guidelines.

May 2021 — History Page Added

Added a dedicated history page providing a narrative account of the competition's development from its origins in 2010 to the present. This page supplements the year-by-year records with contextual information about how the competition evolved over time.

2020

September 2020 — Publications Page Overhauled

Substantially expanded the publications page. Added entries for workshop papers, invited talks, and technical reports that had not been previously listed. Improved bibliographic formatting and added abstract summaries for key publications.

January 2020 — Mobile Layout Improvements

Reworked the site layout for better usability on mobile devices. Adjusted font sizes, spacing, and navigation behaviour to improve the reading experience on small screens. The desktop experience was not changed.

2019

July 2019 — Corrections to 2012 Solutions

Fixed errors in two solution summaries from the 2012 edition. One entry had incorrectly attributed a solution to the wrong verification tool; the other had a transcription error in a specification excerpt. Both corrections were verified with the original authors.

2018

November 2018 — Problems Catalogue Reorganised

Reorganised the problems catalogue to support filtering by domain area and difficulty level, in addition to the existing year-based organisation. Added short domain tags (e.g., "sorting," "concurrency," "data structures") to each problem entry.

April 2018 — Site Migrated to New Hosting

Migrated the site to updated hosting infrastructure with improved performance and HTTPS support. All existing URLs were preserved. No content changes were made as part of this migration.

2017

October 2017 — 2017 Edition Materials Published

Published the complete problem set, results, and solution summaries for the 2017 edition of the competition. Added the 2017 year hub page and updated the years index accordingly.

March 2017 — Rules Page Clarified

Revised the rules page to more clearly distinguish between general competition rules that apply across all editions and edition-specific variations. Added a section on evaluation criteria at the request of prospective participants.

2016

August 2016 — Minor Corrections and Formatting Updates

Fixed assorted formatting inconsistencies across the site. Corrected three typographical errors in problem statements from the 2014 and 2015 editions. Standardised the use of mathematical notation across problem descriptions.

2015

November 2015 — 2015 Edition Materials Published

Published the problem set, evaluation results, and solution summaries for the 2015 competition edition. Created the corresponding year hub page and updated navigation links.

June 2015 — Solutions Archive Restructured

Reorganised the solutions archive to group entries by edition and problem. Previously, solutions were listed in a flat chronological order, which made it difficult to compare approaches to the same problem. The new structure allows readers to see all solutions for a given challenge in one place.

2014

December 2014 — 2014 Edition Materials Published

Published the full problem set and results for the 2014 edition. This was the first edition to include an explicit requirement for written documentation of verification strategies. Updated the rules page to reflect this addition.

February 2014 — Publication Records Added

Created the publications page to catalogue academic papers, workshop proceedings, and technical reports associated with the competition. Initial population included publications from 2010 through 2013.

2013

September 2013 — Navigation Reorganised

Reorganised the site navigation to separate the problems, solutions, and years sections more clearly. Added a dedicated problems page consolidating all competition problems across editions.

April 2013 — 2012 Edition Errata Published

Published errata for the 2012 problem set. One problem had an ambiguous precondition that was interpreted differently by several participants. The erratum clarifies the intended interpretation and notes how submitted solutions were evaluated in light of the ambiguity.

2012

November 2012 — 2012 Edition Materials Published

Published the problem set, results, and selected solution summaries for the 2012 edition. Added the 2012 year hub page.

June 2012 — Solution Pages Added

Created individual solution summary pages for notable submissions from the 2010 and 2011 editions. These pages include brief descriptions of the verification approach, the tool used, and links to any associated publications.

2011

October 2011 — 2011 Edition Materials Published

Published the problem set and results for the 2011 edition. Added the corresponding year hub page with links to problem statements and participant information.

March 2011 — FAQ Section Added

Added an initial FAQ section addressing common questions from prospective participants about the competition format, eligible tools, and submission procedures. The FAQ was based on questions received via email following the 2010 pilot edition.

2010

November 2010 — 2010 Edition Results Published

Published the results and summary of the inaugural edition. Added an overview of submitted solutions and the evaluation methodology used. Created the first year hub page.

August 2010 — Problem Set Published

Published the problem set for the 2010 competition edition. Five verification challenges were presented, covering areas including sorting, arithmetic, and data-structure invariants.

June 2010 — Site Established

Set up the initial website for the Verified Software Competition. The site included an overview of the competition's purpose, the rules for the first edition, and information on how to participate. Initial content drew on planning discussions within the formal-methods community about the value of a competitive benchmark for verification tools.

This changelog records changes to the website itself. For information about the competition editions, including timelines, participants, and results, see the competition years index. For the history and development of the competition as an academic endeavour, see the history page.