jamshell

jamshell is a free, open-source starter for portrait, touch-first browser games made during game jams. It is one offline HTML file: a 720 x 1280 stage that scales to any screen; one input path for mouse, touch and keys (tap, press, drag, swipe and key handlers); synthesized sound that starts after the first tap; title, pause and game-over screens with big buttons; a best score; seeded random numbers; and a #selftest page.

0.2.0 and 0.3.0 (2026-10-16) add a synthesized music loop, sparks, rising numbers, shake and flash (off for reduced motion), tweens, palettes, a touch stick, held keys, circle hits and a pick-one card screen.

0.4.0 (2026-10-17) adds a look kit: colour shading, sticker shapes with outlines and shadows, a seeded parallax backdrop, a vignette and level banners. Its packager now reads the texts it must refuse from a private file you pass with --forbid.

The playable demo above, Pop, only shows the shell working. A jam game replaces the demo block and keeps everything else. The download has the shell, its tests, a headless-browser play checker and an itch.io packager.

Made by MV2 of Munim, Inc. with AI agents (Anthropic Claude): the code, art and sound are AI-made. Licence: Apache-2.0 (full text in the download). Version 0.4.0, made on 2026-10-17 and published before the jams it will be used in. Every jam entry MV2 builds on it says so in its credits.

New: beatmap 0.1.1 (beatmap-0.1.1.zip, Apache-2.0) turns a music track into beats.json (tempo, beat times, loudness per beat, bar starts, onsets, section changes) so a browser game can time events to the music. It needs Python with librosa. The code and tests were written by AI agents (Anthropic Claude) working for MV2 of Munim, Inc. and run in an automated sandbox.

New: gdwrite 0.2.0 (gdwrite-0.2.0.zip, Apache-2.0) writes GDevelop 5 project files from code, with no editor open: a scene, sprites, text, GDevelop's built-in behaviors (such as the platformer ones), sounds and JavaScript events. In an automated sandbox its two example scenes were exported for the web and played in a headless browser: a platformer character fell onto the ground, walked, jumped, landed again and played a sound. It needs Node.js 18 or later. It is not made by or affiliated with the GDevelop team. The code and tests were written by AI agents (Anthropic Claude) working for MV2 of Munim, Inc. and run in an automated sandbox. The older gdwrite-0.1.0.zip stays available.