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+# Claro RC0 Notes
+
+Claro RC0 is a stabilization pass for the educational scripting-language core.
+
+## Goal
+
+The goal of RC0 is to make Claro feel safe to try with learners:
+
+- the interpreter builds from source
+- the examples use one consistent style
+- the regression tests pass
+- docs and version labels no longer describe the project as a random beta snapshot
+- older experimental pieces are clearly separated from the portable core
+
+## What changed
+
+The uploaded beta source had many build blockers and internal inconsistencies. RC0 replaces that broken interpreter snapshot with a compact C99 interpreter that focuses on the language features needed for a first public testing release.
+
+Validated features include:
+
+- output and input with `SAY` and `ASK`
+- variables and expressions
+- functions using `TEACH`, `CALL`, `RETURN`, and `LEARNED`
+- conditionals and loops
+- lists and maps
+- map/list iteration
+- file commands
+- JSON parse/make/pretty output
+- imports, namespaces, and exports
+- error handling with `TRY`, `CATCH`, `RAISE`, and `LASTERROR`
+- text, math, random, and CSV stdlib-style imports
+- formatter/check/test CLI commands
+
+## Test result
+
+On the RC0 staging build:
+
+```text
+PASS: 0 failure(s)
+```
+
+This covers all `tests/*.claro` files with matching `.out` expected-output files.
+
+## Accessibility direction
+
+Claro should remain predictable and visually calm:
+
+- plain-English commands
+- indentation-based teaching style
+- minimal symbolic punctuation
+- short examples
+- clear error text
+- no mandatory advanced setup for early lessons
+
+Future documentation should continue using print-friendly layouts, larger examples, and OpenDyslexic/OpenDyslexia-friendly exports where possible.
+
+## Known limitations
+
+- RC0 is not final 1.0.
+- SDL 1.2 game examples from older betas are preserved in `examples/experimental_sdl/`, but SDL is not part of the portable RC0 core.
+- The checker is intentionally lightweight.
+- Runtime safety limits and richer semantic diagnostics should be strengthened before final 1.0.
+- The C interpreter favors readability and portability over speed.
+
+## Recommended next milestone
+
+For RC1:
+
+1. add more beginner lessons and teacher notes
+2. expand semantic checking for friendlier mistakes
+3. add a print-friendly quick-start PDF generated from the updated syntax
+4. add Windows CI-style build/test instructions
+5. decide whether SDL/game support belongs in core or a separate optional build