Here you'll find set of useful KickAssembler libraries for native Commodore 64 development as well as a few supporting tools.

Documentation for libraries: https://c64lib.github.io/.

A backbone build system that I wrote, maintain and use myself is pretty well documented: https://c64lib.github.io/gradle-retro-assembler-plugin/.

There are few examples of using both libs and the tooling on my private space: https://github.com/maciejmalecki/, including:

• https://github.com/maciejmalecki/bluevessel/ (a sample C64 intro/one file demo, heavy usage of Copper64 library).
• https://github.com/maciejmalecki/trex64/ (a preview of C64 full-screen side-scrolling game, heavy usage of Copper 64 and Text libs).
• https://github.com/c64lib/ctm-viewer/ (a multic bitmap viewer for testing Charpad 3.0 capabilities and Gradle build tool).
• https://github.com/maciejmalecki/tony-demo/ (a source code of demo version of the game: Tony: Montezuma's Gold