Full self-hosting parity, differential testing, MIT license, flagship demo

.github/workflows/ci.yml

@@ -21,43 +21,32 @@ jobs:
       - name: Run unit tests
         run: cargo test --release
 
-      - name: Syntax check — test_core.ep
-        run: cargo run --release -- --check tests/test_core.ep
+      - name: Full test suite (run_tests.sh)
+        run: ./run_tests.sh
 
-      - name: Syntax check — test_strings.ep
-        run: cargo run --release -- --check tests/test_strings.ep
+      - name: Build the self-hosted compiler (epc)
+        run: ./target/release/ernos epc.ep
 
-      - name: Syntax check — test_math.ep
-        run: cargo run --release -- --check tests/test_math.ep
+      - name: Self-hosted parity + rejection suite
+        run: bash tests/run_epc_parity.sh
 
-      - name: Syntax check — test_data.ep
-        run: cargo run --release -- --check tests/test_data.ep
+      - name: Differential suite (ernos vs epc must agree)
+        run: bash tests/run_differential.sh
 
-      - name: Compile and run test_core.ep
-        run: |
-          cargo run --release -- tests/test_core.ep
-          ./tests/test_core
-
-      - name: Compile and run test_strings.ep
-        run: |
-          cargo run --release -- tests/test_strings.ep
-          ./tests/test_strings
+      - name: 3-stage self-compilation fixpoint (gen2 == gen3)
+        run: bash tests/run_fixpoint.sh
 
-      - name: Compile and run test_math.ep
-        run: |
-          cargo run --release -- tests/test_math.ep
-          ./tests/test_math
+      - name: Clang-only bootstrap (no Rust) — build, fixpoint, freshness
+        run: bash bootstrap/verify.sh
 
-      - name: Compile and run test_float_ffi.ep
+      - name: Flagship demo — both compilers, identical output
         run: |
-          cargo run --release -- tests/test_float_ffi.ep
-          ./tests/test_float_ffi
-
-      - name: Compile demo — creature_quest_demo5.ep
-        run: cargo run --release -- demos/creature_quest_demo5.ep
-
-      - name: Syntax check — epc.ep (self-hosted compiler)
-        run: cargo run --release -- --check epc.ep
+          ./target/release/ernos examples/bakery.ep
+          ./examples/bakery > /tmp/bakery_rust.out
+          ./epc examples/bakery.ep
+          ./examples/bakery > /tmp/bakery_epc.out
+          diff /tmp/bakery_rust.out /tmp/bakery_epc.out
+          echo "flagship output identical across compilers"
 
       - name: Run conformance tests
         run: |
@@ -90,39 +79,40 @@ jobs:
         uses: dtolnay/rust-toolchain@stable
 
       - name: Install build dependencies
-        run: sudo apt-get update && sudo apt-get install -y gcc
+        run: sudo apt-get update && sudo apt-get install -y clang
 
       - name: Build (release)
         run: cargo build --release
 
       - name: Run unit tests
         run: cargo test --release
 
-      - name: Syntax check — test_core.ep
-        run: cargo run --release -- --check tests/test_core.ep
+      - name: Full test suite (run_tests.sh)
+        run: ./run_tests.sh
 
-      - name: Compile and run test_core.ep
-        run: |
-          cargo run --release -- tests/test_core.ep
-          ./tests/test_core
+      - name: Build the self-hosted compiler (epc)
+        run: ./target/release/ernos epc.ep
 
-      - name: Compile and run test_strings.ep
-        run: |
-          cargo run --release -- tests/test_strings.ep
-          ./tests/test_strings
+      - name: Self-hosted parity + rejection suite
+        run: bash tests/run_epc_parity.sh
 
-      - name: Compile and run test_math.ep
-        run: |
-          cargo run --release -- tests/test_math.ep
-          ./tests/test_math
+      - name: Differential suite (ernos vs epc must agree)
+        run: bash tests/run_differential.sh
 
-      - name: Compile and run test_float_ffi.ep
-        run: |
-          cargo run --release -- tests/test_float_ffi.ep
-          ./tests/test_float_ffi
+      - name: 3-stage self-compilation fixpoint (gen2 == gen3)
+        run: bash tests/run_fixpoint.sh
+
+      - name: Clang-only bootstrap (no Rust) — build, fixpoint, freshness
+        run: bash bootstrap/verify.sh
 
-      - name: Syntax check — epc.ep (self-hosted compiler)
-        run: cargo run --release -- --check epc.ep
+      - name: Flagship demo — both compilers, identical output
+        run: |
+          ./target/release/ernos examples/bakery.ep
+          ./examples/bakery > /tmp/bakery_rust.out
+          ./epc examples/bakery.ep
+          ./examples/bakery > /tmp/bakery_epc.out
+          diff /tmp/bakery_rust.out /tmp/bakery_epc.out
+          echo "flagship output identical across compilers"
 
       - name: Run conformance tests
         run: |

.gitignore

@@ -103,3 +103,13 @@ tests/*
 !tests/*.ep
 !tests/*.expected
 !tests/*.md
+!tests/*.sh
+
+# Bootstrap build output (keep the frozen C, not the binary)
+/epc-bootstrapped
+
+# Debug bundles under tests/ (the !tests/*/ negation would otherwise re-include them)
+tests/**/*.dSYM/
+/epc_stage1
+bakery_report.txt
+examples/bakery

AGENT.md

@@ -56,9 +56,21 @@ If a function isn't registered in `src/type_check.rs` (`register_builtins`) AND
 ```bash
 # This MUST pass after any change to the type system, parser, or codegen:
 cargo run -- epc.ep && ./epc tests/test_basic_math.ep && ./test_basic_math
+
+# Stronger gates (run after any epc-visible change):
+bash tests/run_fixpoint.sh      # 3-stage byte-identical self-compile
+bash tests/run_epc_parity.sh    # self-hosted coverage scoreboard (must not regress)
+bash tests/run_differential.sh  # both compilers must AGREE on 37 adversarial programs
+bash bootstrap/verify.sh        # clang-only, Rust-free 3-stage fixpoint + parity + freshness
 ```
 
-The self-hosted compiler is 5,800+ lines of real ErnosPlain that exercises the full type system, all builtin functions, list operations, string operations, struct creation, pattern matching, and closures. If it doesn't compile, you broke something.
+Current state of these gates: `run_tests.sh` **71/71**, `run_epc_parity.sh` **53/53 runnable + 12/12 compile-error rejections** (0 wrongly accepted), `run_differential.sh` **37/37 agree**, `run_fixpoint.sh` byte-identical, `bootstrap/verify.sh` green.
+
+The self-hosted compiler is ~6,400 lines of real ErnosPlain — `ep_lexer.ep` (lexer), `ep_parser.ep` (parser), `ep_check.ep` (semantic checker), `ep_optimizer.ep` (constant folding + DCE), `ep_codegen.ep` (C codegen), `epc.ep` (driver) — that exercises the full type system, all builtin functions, list/string operations, struct creation, pattern matching, closures, floats, traits, `try`/Result, and coroutine async. If it doesn't compile, you broke something.
+
+**Shared runtime.** `runtime/ep_runtime.c` + `runtime/ep_builtins.c` are the single source of truth for the emitted C runtime. The Rust compiler embeds them via `include_str!`; the self-hosted compiler embeds them via the generated `ep_runtime_gen.ep`. After editing either `runtime/*.c` file, regenerate: `./target/release/ernos tools/gen_runtime_ep.ep && ./tools/gen_runtime_ep`.
+
+**Bootstrap freshness.** `bootstrap/epc_bootstrap.c` is `epc` compiled by `epc`. After ANY change that alters epc's output, regenerate it in the same commit: `./epc epc.ep && cp epc_compiled.c bootstrap/epc_bootstrap.c`. `bash bootstrap/verify.sh` enforces freshness and the clang-only fixpoint.
 
 ### Rule 5: Read Source, Never Guess
 
@@ -144,7 +156,7 @@ Every language construct should read like a sentence a non-programmer could unde
 Symbol shortcuts (`+`, `<`, `==`, `&&`) are allowed as opt-in shorthands for experienced programmers. The plain English form is always the primary syntax.
 
 ### Self-Hosting is Non-Negotiable
-The self-hosted compiler (`epc.ep` + modules) must always compile itself using the Rust bootstrap compiler. This is the ultimate integration test. If the type checker rejects the self-hosted compiler, the type checker is too strict — not the self-hosted compiler is wrong. The self-hosted compiler is 5,800+ lines of real, working ErnosPlain. It is the language's own dogfood.
+The self-hosted compiler (`epc.ep` + modules) must always compile itself using the Rust bootstrap compiler. This is the ultimate integration test. If the type checker rejects the self-hosted compiler, the type checker is too strict — not the self-hosted compiler is wrong. The self-hosted compiler is ~6,400 lines of real, working ErnosPlain. It is the language's own dogfood, and it bootstraps from a frozen C snapshot with no Rust in the loop.
 
 ### Cross-Platform by Default
 Ernos must work on:
@@ -508,7 +520,7 @@ Usage: `import "stdlib/bridge/sqlite"` — all functions use `ep_dlopen`/`ep_dls
 - Source files: `snake_case.ep`
 - Test files: `tests/test_feature_name.ep` with optional `tests/test_feature_name.expected`
 - Stdlib modules: `stdlib/module_name.ep`
-- Self-hosted compiler: `epc.ep`, `ep_lexer.ep`, `ep_parser.ep`, `ep_codegen.ep`
+- Self-hosted compiler: `epc.ep`, `ep_lexer.ep`, `ep_parser.ep`, `ep_check.ep`, `ep_optimizer.ep`, `ep_codegen.ep` (+ generated `ep_runtime_gen.ep`)
 - Generated C: `filename_compiled.c` (temporary, cleaned up by compiler)
 - Generated binary: `./dirname/filename` (next to source file, same stem)
 

LICENSE

@@ -0,0 +1,21 @@
+MIT License
+
+Copyright (c) 2026 MettaMazza
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.