SkyPop

Dodge bouncing balls, fire ropes to split them, and clear ten increasingly
fast stages. Collect health, shields and weapon upgrades while avoiding
steel balls, bombs and fireballs. Includes fullscreen play, local high
scores, controller support and adjustable music and effects.
Source code is available under Apache-2.0; bundled media has separate terms.

Controls: A/D or arrows to move; W/up to jump; S/down to crouch; Space to fire; E for special; 1/2/3 or Q for rope selection. F11 toggles fullscreen, Escape pauses, F1 opens settings and M toggles music.

QuietByte: hello@quietbytehq.uk
Source and Windows downloads: https://github.com/quietbytehq/skypop

Code is Apache-2.0. Bundled media has separate terms; the complete download is marked Proprietary. The game has no online accounts or network gameplay.