sunsided

Commodore 64 BASIC V2: programming rules, the three data types (integer, floating-point, string) and their constants/variables/arrays, expressions, arithmetic/relational/logical operators and precedence, string handling, INPUT/GET, program crunching, and the…

Workflow for reverse-engineering existing Commodore 64 code — .prg/.bin files, cartridge dumps, memory snapshots, and raw 6510 listings. Covers the .prg load address, the tokenized BASIC stub and its SYS launcher, classifying every address as RAM / ROM call /…

The two Commodore 64 control (game) ports: reading joysticks, paddles, a light pen, and mouse, and how they map to hardware registers (CIA1 $DC00/$DC01, SID POT $D419/$D41A, VIC light-pen $D013/$D014). Use this skill WHEN a user asks "which port is player 1",…

C64 screen graphics from the programmer's view: the five VIC-II display modes (standard/multicolor text, ECM, standard/multicolor bitmap), custom 8x8 character sets, screen/color/character memory layout, video bank selection, and smooth scrolling. Use this…

The C64 keyboard and screen editor: every special key and what it does — the Commodore (C=) key, CTRL, RUN/STOP, RESTORE, SHIFT / SHIFT-LOCK, CLR/HOME, INST/DEL, cursor (CRSR) keys, function keys f1–f8, RETURN — plus screen-editor behavior (quote mode, insert…

The complete Commodore 64 memory map and banking: zero page, stack, the BASIC program area and pointers, screen and color RAM, the $D000-$DFFF I/O area, the BASIC/KERNAL/character ROMs, the $0000/$0001 6510 port plus the 82S100 PLA that switches…

Commodore 64 hardware sprites (MOBs, movable object blocks): the 24x21-pixel / 63-byte sprite shape, sprite pointers, enabling sprites, X/Y positioning including the X MSB ($D010) for positions past 255, sprite color, multicolor sprites, 2x X/Y expansion,…

The physical Commodore 64 and its servicing: system specs, the chip complement (6510, VIC-II, SID, two CIAs, PLA, ROMs, DRAM) and each chip's role, the circuit theory (power, reset, clock, video/audio, ports), board revisions and how to ID them, connector…

Use when setting up asset loading, designing asset handles/registries, building offline asset processing tools, implementing hot reload, loading spritesheets or atlases, or deciding how to organize game asset directories.

Use when adding or modifying audio playback, sound mixing, music systems, or real-time audio synthesis in a Rust game. Trigger when user mentions rodio, cpal, sound effects, music playback, audio mixer, or procedural audio.

Use ONLY when the project already uses Bevy (bevy in Cargo.toml) or the user explicitly asks about Bevy. Do not trigger for custom wgpu/winit/ECS projects. Use when working with Bevy plugins, components, systems, states, the Bevy asset server, schedules, or…

Use when adding egui debug overlays, frame timing panels, entity inspectors, renderer stat displays, in-game feature toggles, or puffin profiler integration to a Rust game. Also use when the user asks how to add a debug view or troubleshoot via in-game…

Use when designing ECS component layouts, system ordering, event systems, deferred spawning/despawning, fixed vs variable update schedules, or deciding how game world data flows to the renderer. Use for both custom ECS and library ECS (hecs, legion).

Use ONLY when the project uses Godot with Rust (gdext or gdnative in Cargo.toml, or .gdextension file present). Do not trigger for pure Rust/wgpu projects. Use when working with GodotClass,

Use when setting up input handling, designing action maps, rebindable controls, gamepad support, mouse delta handling, input buffering, or deciding how raw winit events should flow to gameplay code.

Use when preparing a Rust game for distribution, setting up release builds, bundling assets, creating Linux/Windows/macOS packages, or configuring asset path resolution for deployed executables.

How to read and write 6502/65C02/65816 assembly source for the Merlin macro assembler (Merlin 8, Merlin Pro, Merlin 16/16+, Merlin 32 on Apple II/IIgs, and Merlin 64/128 on Commodore). Covers Merlin's source column layout, its pseudo-opcodes/directives (ORG,…

Reference and semantics for the MOS 6502 / 65C02 / 65816 instruction set: mnemonics, addressing modes, opcode bytes, cycle counts, and exact flag effects. Use this skill WHENEVER you read, write, disassemble, trace, explain, or port 6502-family assembly…

Memory maps, I/O register layouts, ROM entry points, and zero-page conventions for the main 6502 home computers: the Apple II family, the Commodore 64, and the Atari 400/800/XL/XE. Covers Apple II soft switches ($C000-$C0FF), language card, Monitor ROM and…

Reference for SWEET16, Steve Wozniak's 16-bit interpreted pseudo-processor built into the Apple II Integer BASIC ROM (entry $F689). SWEET16 is a tiny virtual machine with sixteen 16-bit registers (R0-R15) living in zero page, invoked by JSR SWEET16 followed…

A workflow for porting 6502/65C02/65816 assembly (Apple II, Commodore 64, Atari 8-bit, NES, Merlin source, SWEET16) to modern Rust by first lifting it to an explicit intermediate language (IL) and then raising that IL to idiomatic Rust. Covers the two-stage…

Use whenever the user wants to open a pull request, draft a PR description, or says anything like "open a PR", "write a PR description", "create a pull request", "draft the PR body", or "/pr". Analyzes the diff between the current branch and its base, detects…

Use whenever the user wants to commit changes, split a working tree into commits, write a commit message, or says anything like "commit this", "make commits for these changes", "write a commit message", or "/commit". Detects the repository's commit style…

Use when the user wants to author Taskfile content: creating new Taskfiles, adding new tasks, writing task dependencies/preconditions/variables, or restructuring tasks across files. The user might say "add a [name] task", "set up tasks for", "create a…

Taskfile discovery and execution — use before running any project command when the project may use go-task. Invoke when the user asks: "run the tests", "build the project", "start the dev server", "run lint/fmt/bench/ci/clean", "what task should I run for X",…

Use when understanding or changing code in this repo: locating where a symbol is defined, what calls it, how a request flows across the API boundary, or the blast radius of a change (which symbols, tests, endpoints — and which other indexed repos — a change…

Use when reading, parsing, writing, dumping, or debugging any Jill of the Jungle data file (DMA, SHA, JN, MAC, CFG, VCL, CMF/DDT, Crunched Screen Image) or when reasoning about its byte layout, flag bits, object iTypes, savegame structure, palette handling,…