Write or review code in the BlitzForge language (a modernized Blitz3D fork used by rcce2 and other projects). Invoke whenever editing, reviewing, or generating any `.bb` file — INCLUDING when the user only says "Blitz", "Blitz3D", "BlitzBasic", or shows .bb source — because your training data is base Blitz3D from ~2003 and does not have BlitzForge's modern additions (Strict mode, garbage collection, type inheritance, methods, BBList, function pointers, Async/Await, Try/Catch/Throw, the `Continue` keyword, `//` and `/* */` comments). Without this skill you WILL write outdated code that fails to compile under Strict or misses safer modern alternatives.
Add, modify, or audit a BVM scripting command in rcce2. Invoke whenever the user wants to expose a new built-in function to Blitz game scripts (the BVM_* function family in ScriptingCommands.bb), tweak the dispatch table in RC_Standard_Invoker.bb, fix a BVM bounds check, change a function's privilege gating, or audit a scripting-engine vulnerability. Critical to know: BVM opcodes are assigned ALPHABETICALLY by function name. Inserting a single new function in the middle of the alphabet shifts every subsequent opcode by 1, requiring renumbering hundreds of dispatch cases — easy to corrupt the table by hand. This skill documents the safe insertion procedure, the privilege gating rules, the bounds-check patterns, and the SAFE-APPEND ordering trick that lets you avoid renumbering.
Add, modify, or harden a packet handler in rcce2's ServerNet.bb or ClientNet.bb. Invoke whenever the work involves the wire protocol — adding a new P_* packet type, fixing a Mid$ offset bug, hardening a handler against malformed input, adding a Case branch to the giant Select Case on packet type, or any code that calls RCE_Send / RCE_StrFromInt$ / RCE_IntFromStr. The wire encoding has subtle conventions (length-prefixed strings, fixed-byte integer fields, paired sender/receiver byte counts) and the server is a single shared process — one unchecked Mid$ or one unguarded array index is a one-packet client-to-server DoS for every connected player. This skill encodes the established encoding, validation, and soft-fail patterns from the existing handlers.
Write or modify a unit test under src/Tests/ in rcce2. Invoke whenever the user asks to test a module, cover a bug fix with a regression test, add coverage for a serialization round-trip, or asks about the test framework's Strict-mode + inline-stub pattern. Also invoke when CI is failing on a test file, when the known intermittent "ItemsTest Stack overflow" flake appears, or when the user wants to understand why a test compiles standalone but breaks under test.bat. The rcce2 test framework has a specific structure (Strict + EnableGC + inline type/function stubs to keep the dependency graph small) that does NOT match generic Blitz3D testing, and the build runner has a known-flake retry workflow that's documented nowhere else.