Engine Arena 1.9.7 — Stable Release

Engine Arena 1.9.7 brings the development work since 1.2.14 into a new stable release: persistent ratings, configurable seasons, Player Arena, richer board/room choices, and workflow and recovery improvements.

Designed by Mark Young. Coding and implementation by OpenAI Codex, under Mark Young's direction.

Downloads

File	Size	Use
EngineArenaSetup-1.9.7-win-x64.exe	900.3 MB	Complete offline installer. Includes Python, .NET, WebView2 setup, optional PawnIO setup and corresponding application source.
EngineArena-1.9.7-win-x64.zip	415.3 MB	Smaller extract-and-run application. Same features, boards, rooms and pieces. Requires Microsoft WebView2 Runtime already installed.

The ZIP is about 54% smaller. It leaves out the offline WebView2 installer and duplicate application-source folder. Python, .NET, third-party notices and applicable dependency-source archives remain included. Matching application source is available in GitHub's Source code downloads and the v1.9.7 source tree.

Windows 11 x64 (Intel/AMD). Extract the ZIP completely before opening EngineArena.exe. It creates no Start menu entries or uninstaller. If WebView2 is missing, use the full installer. Both packages use the same default saved-data folder, %LOCALAPPDATA%\EngineArena\Data; close the other copy first. Use --data to choose a separate workspace.

For an update, pause and drain games, close Engine Arena, then run setup in the existing installation folder. For the ZIP, extract into a fresh folder. Saved engines, tournaments, events and ratings are retained. Intermediate updates are not required. Leave optional WebView2 repair unchecked when the runtime already works. Add your own chess engines and opening books. Engine Arena itself is unsigned.

Highlights

• Rating Center: automatically collect ratings across tournaments, use optional anchors and time-control categories, distinguish thread/GPU configurations, and display the best version per engine family. Compact rating records can survive tournament deletion; automatic collection and retention default to on.
• Seasons and events: qualification and division placement, configurable field/admission controls, roster and engine-version reviews, promotion/relegation, custom multi-stage competitions with different formats and time controls, championship tiebreaks, careers and shareable summaries.
• Player Arena: play engines using mouse click or drag on 2D/3D boards, with opening books, clocks, thinking panels, sounds, saved PGNs, challenge series and separate personal ratings. Panels resize, dock and float.
• Board presentation: detailed 1849-style Staunton and Tal 1962 sets, more wooden boards, photographic rooms, an animated chess club, camera tours, low-angle views and 4K photographs. Live-room animation is capped at 30 FPS.
• Testing workflow: extend a completed standalone round robin by adding engines and scheduling only missing matchups; improved engine-library bulk controls, event summaries, move history, draw-rule counters and resize/sound behavior.

All ten tournament formats, simultaneous tournaments with shared CPU/GPU budgets, queues, Banksia/Cute Chess engine-profile importing, independent engine books, SPRT, suites/benchmarks, pure fixed-node controls, automatic PGNs, preserved failure attempts and recovery remain available.

Final checks and fixes

850 Python tests and 96 JavaScript tests passed. Packaged checks covered all ten formats, seasons, statistics, recovery, original-attempt preservation, ratings, reports, four PGN presets, Player Arena and eight languages. A 256-game test ran at up to 28 concurrent games; storage cleanup preserved all compact rating records. A further 12-game test passed after installation. The extracted ZIP also passed startup, four games, PGN/report generation and clean restart.

Final fixes include clearer completed-event/final-match summaries, Quick match PGN saving, focused-board sound after resizing, proper opening move labels, stable ordering of same-timestamp tournament drafts, and the patched multidict 6.9.1 dependency.

These are bounded functional/scaling checks, not a guarantee for every engine or graphics driver. Graphics recovery tests use software WebGL and simulated context loss; no new overnight GPU endurance run is claimed.

The installer is the exact tested file, unchanged for publication; some bundled documents retain their earlier candidate wording. The public documentation and ZIP instructions record the release approval. SHA-256 checksums and a concise validation receipt accompany the downloads.

Full release notes and validation scope · User guide · Report an issue