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README.md

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+# wasm-runtime
+
+A WebAssembly runtime for KolibriOS, written in FASM.
+
+Currently builds as a Linux binary for easier development and testing. The final target is KolibriOS native format.
+
+## What it does right now
+
+Parses a `.wasm` binary and prints out everything it finds — sections, types, imports, exports, and function signatures in a readable format:
+
+```
+$ ./src/wasm test/wasm/add.wasm
+Valid wasm file
+File size: 41 bytes
+Section 1 (Type), size: 7 bytes
+  type 0: (i32, i32) -> (i32)
+Section 3 (Function), size: 2 bytes
+  func 0 -> type 0
+Section 7 (Export), size: 7 bytes
+  export "add" -> func 0
+Section 10 (Code), size: 9 bytes
+  body 0: 7 bytes
+Function index: 1 entries
+  func 0 -> type 0 (local)
+Function signatures:
+  i32 add(i32, i32)
+```
+
+## What's implemented
+
+- wasm binary header validation (magic number + version)
+- LEB128 decoding (unsigned and signed)
+- section enumeration (all 13 section types recognized)
+- type section parsing (function signatures with i32/i64/f32/f64)
+- import section parsing (functions, tables, memories, globals)
+- export section parsing
+- function section + code section parsing
+- unified function index (imports first, then locals, per spec)
+- human-readable function signature output
+
+## Build
+
+```
+fasm src/wasm.asm src/wasm
+chmod +x src/wasm
+```
+
+## Test
+
+```
+sh test/build_wasm.sh   # compile .wat files to .wasm (needs wat2wasm)
+sh test/run_tests.sh    # run from repo root
+```
+
+## Structure
+
+```
+src/
+  wasm.asm       main entry point
+  leb128.inc     LEB128 variable-length integer decoder
+  sections.inc   section parsers
+test/
+  wat/           source .wat files
+  wasm/          compiled .wasm binaries
+  build_wasm.sh  compiles wat -> wasm
+  run_tests.sh   test runner
+```