[M6] Phase 2 self-hosting: cargoxx builds itself from Cargoxx.toml

.gitignore

@@ -1,5 +1,6 @@
 # Build outputs
-/build/
+/build/*
+!/build/CMakeLists.txt
 /result
 /result-*
 

CMakeLists.txt

@@ -1,96 +0,0 @@
-cmake_minimum_required(VERSION 3.30)
-
-# Opt into experimental C++ modules dyndep + `import std;` support.
-# Required until CMake declares these stable; see CMake docs for the current UUID.
-set(CMAKE_EXPERIMENTAL_CXX_MODULE_DYNDEP 1)
-set(CMAKE_EXPERIMENTAL_CXX_IMPORT_STD "d0edc3af-4c50-42ea-a356-e2862fe7a444")
-set(CMAKE_CXX_MODULE_STD ON)
-
-project(cargoxx LANGUAGES CXX VERSION 0.1.0)
-
-# Phase 0: hand-written CMakeLists.txt. Replaced by generated build/CMakeLists.txt
-# at milestone M3 once cargoxx can build itself. See TECH_SPEC.md §15.
-
-set(CMAKE_CXX_STANDARD 23)
-set(CMAKE_CXX_STANDARD_REQUIRED ON)
-set(CMAKE_CXX_EXTENSIONS ON)
-set(CMAKE_CXX_SCAN_FOR_MODULES ON)
-set(CMAKE_EXPORT_COMPILE_COMMANDS ON)
-
-if(NOT CMAKE_BUILD_TYPE)
-    set(CMAKE_BUILD_TYPE Debug CACHE STRING "Build type" FORCE)
-endif()
-
-# TECH_SPEC.md §17: -Wall -Wextra -Wpedantic -Wconversion, -Werror in CI.
-add_compile_options(-Wall -Wextra -Wpedantic -Wconversion)
-
-option(CARGOXX_WERROR "Treat warnings as errors" OFF)
-if(CARGOXX_WERROR)
-    add_compile_options(-Werror)
-endif()
-
-find_package(SQLite3 REQUIRED)
-find_package(reproc REQUIRED)
-
-# ----- cargoxx library: module units + implementation units -----
-add_library(cargoxx STATIC)
-target_include_directories(cargoxx SYSTEM PRIVATE third_party)
-target_sources(cargoxx
-    PRIVATE
-        src/util/error.cpp
-        src/util/semver.cpp
-        src/manifest/parser.cpp
-        src/manifest/writer.cpp
-        src/layout/layout.cpp
-        src/lockfile/lockfile.cpp
-        src/linkdb/database.cpp
-        src/linkdb/overlay.cpp
-        src/codegen/flake.cpp
-        src/codegen/cmake.cpp
-        src/exec/subprocess.cpp
-        src/resolver/nixpkgs_probe.cpp
-        src/resolver/nix_cmake_scan.cpp
-        src/resolver/pc_scan.cpp
-        src/resolver/conan_probe.cpp
-        src/resolver/vcpkg_probe.cpp
-        src/resolver/verify_link.cpp
-        src/resolver/discover.cpp
-        src/resolver/search_devbox.cpp
-        src/resolver/nixpkgs_git.cpp
-        src/resolver/version_resolve.cpp
-        src/cli/cmd_new.cpp
-        src/cli/cmd_build.cpp
-        src/cli/cmd_run.cpp
-        src/cli/cmd_test.cpp
-        src/cli/cmd_clean.cpp
-        src/cli/cmd_add.cpp
-        src/cli/cmd_remove.cpp
-        src/cli/cmd_linkdb_add.cpp
-        src/cli/run.cpp
-    PUBLIC
-        FILE_SET CXX_MODULES FILES
-            src/lib.cppm
-            src/util/util.cppm
-            src/exec/exec.cppm
-            src/manifest/manifest.cppm
-            src/lockfile/lockfile.cppm
-            src/layout/layout.cppm
-            src/linkdb/linkdb.cppm
-            src/resolver/resolver.cppm
-            src/codegen/codegen.cppm
-            src/cli/cli.cppm
-)
-
-target_link_libraries(cargoxx PRIVATE SQLite::SQLite3 reproc)
-
-# ----- cargoxx binary -----
-add_executable(cargoxx_bin src/main.cpp)
-set_target_properties(cargoxx_bin PROPERTIES OUTPUT_NAME cargoxx)
-target_link_libraries(cargoxx_bin PRIVATE cargoxx)
-
-# ----- tests -----
-option(CARGOXX_BUILD_TESTS "Build cargoxx tests" ON)
-if(CARGOXX_BUILD_TESTS)
-    enable_testing()
-    add_subdirectory(tests)
-endif()

Cargoxx.lock

@@ -0,0 +1,24 @@
+version = 1
+
+[[package]]
+dependencies = [ 'reproc *', 'sqlite *', 'catch2_3 *' ]
+name = 'cargoxx'
+version = '0.1.0'
+
+[[package]]
+linkdb_source = 'nix-probe'
+name = 'reproc'
+nixpkgs_attr = 'reproc'
+version = '*'
+
+[[package]]
+linkdb_source = 'pkg-config'
+name = 'sqlite'
+nixpkgs_attr = 'sqlite'
+version = '*'
+
+[[package]]
+linkdb_source = 'nix-probe'
+name = 'catch2_3'
+nixpkgs_attr = 'catch2_3'
+version = '*'

TECH_SPEC.md

@@ -619,18 +619,17 @@ User-facing errors are formatted via `util::format(Error)` and printed to stderr
 
 ## 15. Bootstrap and self-hosting
 
-Three phases.
+**Phase 0 (historical) — hand-written `CMakeLists.txt` and `flake.nix` at the repo root.**
 
-**Phase 0 — hand-written CMake (commits before milestone M3).**
+**Phase 2 (current, since M6) — fully self-hosted.**
-`CMakeLists.txt` and `flake.nix` at the repo root are written by humans. `cargoxx` builds `cargoxx`.
+`Cargoxx.toml` describes cargoxx's own deps with nixpkgs names: `sqlite`, `reproc`, `catch2_3`. `cargoxx build` runs the auto-resolver chain (nixpkgs probe → realize → nix_cmake_scan → pc_scan), confirms each recipe via verify_link, and generates `build/CMakeLists.txt` and the root `flake.nix`. Both files are committed (tracked) so the build is reproducible without first building cargoxx, and `[build].include_dirs = ["third_party"]` keeps the vendored headers on the include path.
 
-**Phase 1 — generated CMake, hand-written flake.**
+Bootstrap path:
-At milestone M3 (codegen complete), commit a populated `Cargoxx.toml`. Generate `build/CMakeLists.txt` from it. Delete the root `CMakeLists.txt`. The root `flake.nix` stays hand-written because cargoxx doesn't know about its own host-language deps yet.
+```
+pre-built cargoxx → cargoxx build → next cargoxx
+```
 
-**Phase 2 — fully self-hosted.**
+A clean clone with an empty `~/.cache/cargoxx/linkdb.sqlite` auto-resolves all three deps on first `cargoxx build` (sqlite goes through pkg-config because nixpkgs ships no SQLite3Config.cmake; reproc/catch2_3 go through nix_cmake_scan). For continuity, a known-good cargoxx binary is shipped as a release artifact; from-scratch bootstrap is not in v0.1 scope.
-At milestone M5, vendor all third-party headers into `third_party/` and have cargoxx generate the flake too. The bootstrap path becomes: pre-built cargoxx binary → run `cargoxx build` → produce next cargoxx.
-
-For continuity, ship a known-good cargoxx binary as a release artifact. Anyone bootstrapping from source clones the repo, downloads the latest release binary, and runs `./bootstrap-cargoxx build`. If we ever want to bootstrap from absolute zero, `scripts/bootstrap-build.sh` does it with a hand-written CMake invocation.
 
 ---
 

build/CMakeLists.txt

@@ -0,0 +1,351 @@
+cmake_minimum_required(VERSION 3.30)
+
+set(CMAKE_EXPERIMENTAL_CXX_MODULE_DYNDEP 1)
+set(CMAKE_EXPERIMENTAL_CXX_IMPORT_STD "d0edc3af-4c50-42ea-a356-e2862fe7a444")
+set(CMAKE_CXX_MODULE_STD ON)
+
+project(cargoxx LANGUAGES CXX)
+
+# Generated by cargoxx — do not edit.
+# Source of truth: ../Cargoxx.toml
+
+set(CMAKE_CXX_STANDARD 23)
+set(CMAKE_CXX_STANDARD_REQUIRED ON)
+set(CMAKE_CXX_EXTENSIONS ON)
+set(CMAKE_CXX_SCAN_FOR_MODULES ON)
+set(CMAKE_EXPORT_COMPILE_COMMANDS ON)
+
+add_compile_options(-Wall -Wextra -Wpedantic -Wconversion)
+
+# ----- dependencies -----
+find_package(reproc CONFIG REQUIRED)
+find_package(PkgConfig REQUIRED)
+pkg_check_modules(SQLITE3 REQUIRED IMPORTED_TARGET sqlite3)
+find_package(Catch2 CONFIG REQUIRED)
+
+# ----- library target -----
+add_library(cargoxx STATIC)
+target_sources(cargoxx
+    PUBLIC
+        FILE_SET CXX_MODULES BASE_DIRS ${CMAKE_CURRENT_SOURCE_DIR}/.. FILES
+            ../src/cli/cli.cppm
+            ../src/codegen/codegen.cppm
+            ../src/exec/exec.cppm
+            ../src/layout/layout.cppm
+            ../src/lib.cppm
+            ../src/linkdb/linkdb.cppm
+            ../src/lockfile/lockfile.cppm
+            ../src/manifest/manifest.cppm
+            ../src/resolver/resolver.cppm
+            ../src/util/util.cppm
+    PRIVATE
+        ../src/cli/cmd_add.cpp
+        ../src/cli/cmd_build.cpp
+        ../src/cli/cmd_clean.cpp
+        ../src/cli/cmd_linkdb_add.cpp
+        ../src/cli/cmd_new.cpp
+        ../src/cli/cmd_remove.cpp
+        ../src/cli/cmd_run.cpp
+        ../src/cli/cmd_test.cpp
+        ../src/cli/run.cpp
+        ../src/codegen/cmake.cpp
+        ../src/codegen/flake.cpp
+        ../src/exec/subprocess.cpp
+        ../src/layout/layout.cpp
+        ../src/linkdb/database.cpp
+        ../src/linkdb/overlay.cpp
+        ../src/lockfile/lockfile.cpp
+        ../src/manifest/parser.cpp
+        ../src/manifest/writer.cpp
+        ../src/resolver/conan_probe.cpp
+        ../src/resolver/discover.cpp
+        ../src/resolver/nix_cmake_scan.cpp
+        ../src/resolver/nixpkgs_git.cpp
+        ../src/resolver/nixpkgs_probe.cpp
+        ../src/resolver/pc_scan.cpp
+        ../src/resolver/search_devbox.cpp
+        ../src/resolver/vcpkg_probe.cpp
+        ../src/resolver/verify_link.cpp
+        ../src/resolver/version_resolve.cpp
+        ../src/util/error.cpp
+        ../src/util/semver.cpp
+)
+target_include_directories(cargoxx SYSTEM PRIVATE ../third_party)
+target_link_libraries(cargoxx PUBLIC
+    reproc
+    PkgConfig::SQLITE3
+)
+
+# ----- binary target -----
+add_executable(cargoxx_bin ../src/main.cpp)
+set_target_properties(cargoxx_bin PROPERTIES OUTPUT_NAME cargoxx)
+target_link_libraries(cargoxx_bin PRIVATE
+    cargoxx
+    reproc
+    PkgConfig::SQLITE3
+)
+
+# ----- tests -----
+enable_testing()
+include(Catch)
+add_executable(test_cmd_add ../tests/cmd_add.cpp)
+target_link_libraries(test_cmd_add PRIVATE
+    cargoxx
+    reproc
+    PkgConfig::SQLITE3
+    Catch2::Catch2
+    Catch2::Catch2WithMain
+)
+catch_discover_tests(test_cmd_add)
+add_executable(test_cmd_build ../tests/cmd_build.cpp)
+target_link_libraries(test_cmd_build PRIVATE
+    cargoxx
+    reproc
+    PkgConfig::SQLITE3
+    Catch2::Catch2
+    Catch2::Catch2WithMain
+)
+catch_discover_tests(test_cmd_build)
+add_executable(test_cmd_clean ../tests/cmd_clean.cpp)
+target_link_libraries(test_cmd_clean PRIVATE
+    cargoxx
+    reproc
+    PkgConfig::SQLITE3
+    Catch2::Catch2
+    Catch2::Catch2WithMain
+)
+catch_discover_tests(test_cmd_clean)
+add_executable(test_cmd_new ../tests/cmd_new.cpp)
+target_link_libraries(test_cmd_new PRIVATE
+    cargoxx
+    reproc
+    PkgConfig::SQLITE3
+    Catch2::Catch2
+    Catch2::Catch2WithMain
+)
+catch_discover_tests(test_cmd_new)
+add_executable(test_cmd_remove ../tests/cmd_remove.cpp)
+target_link_libraries(test_cmd_remove PRIVATE
+    cargoxx
+    reproc
+    PkgConfig::SQLITE3
+    Catch2::Catch2
+    Catch2::Catch2WithMain
+)
+catch_discover_tests(test_cmd_remove)
+add_executable(test_cmd_run ../tests/cmd_run.cpp)
+target_link_libraries(test_cmd_run PRIVATE
+    cargoxx
+    reproc
+    PkgConfig::SQLITE3
+    Catch2::Catch2
+    Catch2::Catch2WithMain
+)
+catch_discover_tests(test_cmd_run)
+add_executable(test_codegen_cmake ../tests/codegen_cmake.cpp)
+target_link_libraries(test_codegen_cmake PRIVATE
+    cargoxx
+    reproc
+    PkgConfig::SQLITE3
+    Catch2::Catch2
+    Catch2::Catch2WithMain
+)
+catch_discover_tests(test_codegen_cmake)
+add_executable(test_codegen_flake ../tests/codegen_flake.cpp)
+target_link_libraries(test_codegen_flake PRIVATE
+    cargoxx
+    reproc
+    PkgConfig::SQLITE3
+    Catch2::Catch2
+    Catch2::Catch2WithMain
+)
+catch_discover_tests(test_codegen_flake)
+add_executable(test_conan_probe_live ../tests/conan_probe_live.cpp)
+target_link_libraries(test_conan_probe_live PRIVATE
+    cargoxx
+    reproc
+    PkgConfig::SQLITE3
+    Catch2::Catch2
+    Catch2::Catch2WithMain
+)
+catch_discover_tests(test_conan_probe_live)
+add_executable(test_conan_probe_parse ../tests/conan_probe_parse.cpp)
+target_link_libraries(test_conan_probe_parse PRIVATE
+    cargoxx
+    reproc
+    PkgConfig::SQLITE3
+    Catch2::Catch2
+    Catch2::Catch2WithMain
+)
+catch_discover_tests(test_conan_probe_parse)
+add_executable(test_devbox_resolve_live ../tests/devbox_resolve_live.cpp)
+target_link_libraries(test_devbox_resolve_live PRIVATE
+    cargoxx
+    reproc
+    PkgConfig::SQLITE3
+    Catch2::Catch2
+    Catch2::Catch2WithMain
+)
+catch_discover_tests(test_devbox_resolve_live)
+add_executable(test_devbox_resolve_parse ../tests/devbox_resolve_parse.cpp)
+target_link_libraries(test_devbox_resolve_parse PRIVATE
+    cargoxx
+    reproc
+    PkgConfig::SQLITE3
+    Catch2::Catch2
+    Catch2::Catch2WithMain
+)
+catch_discover_tests(test_devbox_resolve_parse)
+add_executable(test_exec_run ../tests/exec_run.cpp)
+target_link_libraries(test_exec_run PRIVATE
+    cargoxx
+    reproc
+    PkgConfig::SQLITE3
+    Catch2::Catch2
+    Catch2::Catch2WithMain
+)
+catch_discover_tests(test_exec_run)
+add_executable(test_layout_discovery ../tests/layout_discovery.cpp)
+target_link_libraries(test_layout_discovery PRIVATE
+    cargoxx
+    reproc
+    PkgConfig::SQLITE3
+    Catch2::Catch2
+    Catch2::Catch2WithMain
+)
+catch_discover_tests(test_layout_discovery)
+add_executable(test_linkdb_lookup ../tests/linkdb_lookup.cpp)
+target_link_libraries(test_linkdb_lookup PRIVATE
+    cargoxx
+    reproc
+    PkgConfig::SQLITE3
+    Catch2::Catch2
+    Catch2::Catch2WithMain
+)
+catch_discover_tests(test_linkdb_lookup)
+add_executable(test_linkdb_overlay ../tests/linkdb_overlay.cpp)
+target_link_libraries(test_linkdb_overlay PRIVATE
+    cargoxx
+    reproc
+    PkgConfig::SQLITE3
+    Catch2::Catch2
+    Catch2::Catch2WithMain
+)
+catch_discover_tests(test_linkdb_overlay)
+add_executable(test_lockfile_round_trip ../tests/lockfile_round_trip.cpp)
+target_link_libraries(test_lockfile_round_trip PRIVATE
+    cargoxx
+    reproc
+    PkgConfig::SQLITE3
+    Catch2::Catch2
+    Catch2::Catch2WithMain
+)
+catch_discover_tests(test_lockfile_round_trip)
+add_executable(test_manifest_parse ../tests/manifest_parse.cpp)
+target_link_libraries(test_manifest_parse PRIVATE
+    cargoxx
+    reproc
+    PkgConfig::SQLITE3
+    Catch2::Catch2
+    Catch2::Catch2WithMain
+)
+catch_discover_tests(test_manifest_parse)
+add_executable(test_manifest_write ../tests/manifest_write.cpp)
+target_link_libraries(test_manifest_write PRIVATE
+    cargoxx
+    reproc
+    PkgConfig::SQLITE3
+    Catch2::Catch2
+    Catch2::Catch2WithMain
+)
+catch_discover_tests(test_manifest_write)
+add_executable(test_nix_cmake_scan_live ../tests/nix_cmake_scan_live.cpp)
+target_link_libraries(test_nix_cmake_scan_live PRIVATE
+    cargoxx
+    reproc
+    PkgConfig::SQLITE3
+    Catch2::Catch2
+    Catch2::Catch2WithMain
+)
+catch_discover_tests(test_nix_cmake_scan_live)
+add_executable(test_nix_cmake_scan_parse ../tests/nix_cmake_scan_parse.cpp)
+target_link_libraries(test_nix_cmake_scan_parse PRIVATE
+    cargoxx
+    reproc
+    PkgConfig::SQLITE3
+    Catch2::Catch2
+    Catch2::Catch2WithMain
+)
+catch_discover_tests(test_nix_cmake_scan_parse)
+add_executable(test_nixpkgs_git_resolve ../tests/nixpkgs_git_resolve.cpp)
+target_link_libraries(test_nixpkgs_git_resolve PRIVATE
+    cargoxx
+    reproc
+    PkgConfig::SQLITE3
+    Catch2::Catch2
+    Catch2::Catch2WithMain
+)
+catch_discover_tests(test_nixpkgs_git_resolve)
+add_executable(test_nixpkgs_probe_live ../tests/nixpkgs_probe_live.cpp)
+target_link_libraries(test_nixpkgs_probe_live PRIVATE
+    cargoxx
+    reproc
+    PkgConfig::SQLITE3
+    Catch2::Catch2
+    Catch2::Catch2WithMain
+)
+catch_discover_tests(test_nixpkgs_probe_live)
+add_executable(test_nixpkgs_probe_parse ../tests/nixpkgs_probe_parse.cpp)
+target_link_libraries(test_nixpkgs_probe_parse PRIVATE
+    cargoxx
+    reproc
+    PkgConfig::SQLITE3
+    Catch2::Catch2
+    Catch2::Catch2WithMain
+)
+catch_discover_tests(test_nixpkgs_probe_parse)
+add_executable(test_semver_satisfies ../tests/semver_satisfies.cpp)
+target_link_libraries(test_semver_satisfies PRIVATE
+    cargoxx
+    reproc
+    PkgConfig::SQLITE3
+    Catch2::Catch2
+    Catch2::Catch2WithMain
+)
+catch_discover_tests(test_semver_satisfies)
+add_executable(test_util_error ../tests/util_error.cpp)
+target_link_libraries(test_util_error PRIVATE
+    cargoxx
+    reproc
+    PkgConfig::SQLITE3
+    Catch2::Catch2
+    Catch2::Catch2WithMain
+)
+catch_discover_tests(test_util_error)
+add_executable(test_vcpkg_probe_live ../tests/vcpkg_probe_live.cpp)
+target_link_libraries(test_vcpkg_probe_live PRIVATE
+    cargoxx
+    reproc
+    PkgConfig::SQLITE3
+    Catch2::Catch2
+    Catch2::Catch2WithMain
+)
+catch_discover_tests(test_vcpkg_probe_live)
+add_executable(test_vcpkg_probe_parse ../tests/vcpkg_probe_parse.cpp)
+target_link_libraries(test_vcpkg_probe_parse PRIVATE
+    cargoxx
+    reproc
+    PkgConfig::SQLITE3
+    Catch2::Catch2
+    Catch2::Catch2WithMain
+)
+catch_discover_tests(test_vcpkg_probe_parse)
+add_executable(test_verify_link_unit ../tests/verify_link_unit.cpp)
+target_link_libraries(test_verify_link_unit PRIVATE
+    cargoxx
+    reproc
+    PkgConfig::SQLITE3
+    Catch2::Catch2
+    Catch2::Catch2WithMain
+)
+catch_discover_tests(test_verify_link_unit)

flake.nix

@@ -1,5 +1,5 @@
 {
-  description = "cargoxx — Cargo-style frontend for modern C++";
+  description = "cargoxx";
 
   inputs = {
     nixpkgs.url = "github:NixOS/nixpkgs/nixos-unstable";
@@ -11,21 +11,22 @@
       let
         pkgs = import nixpkgs { inherit system; };
       in {
-        devShells.default = pkgs.gcc15Stdenv.mkDerivation {
+        devShell = pkgs.gcc15Stdenv.mkDerivation {
-          name = "cargoxx-dev";
+          name = "shell";
-          version = "0.1.0";
+          version = "1.0";
           nativeBuildInputs = [
-            pkgs.cmake
             pkgs.ninja
-            pkgs.git
+            pkgs.cmake
             pkgs.pkg-config
           ];
           buildInputs = [
-            pkgs.sqlite
             pkgs.reproc
+            pkgs.sqlite
             pkgs.catch2_3
           ];
-          hardeningDisable = [ "all" ];
+          hardeningDisable = [
+            "all"
+          ];
         };
       });
 }

tests/CMakeLists.txt

@@ -1,38 +0,0 @@
-find_package(Catch2 3 REQUIRED CONFIG)
-include(Catch)
-
-function(cargoxx_add_test name)
-    add_executable(${name} ${name}.cpp)
-    target_link_libraries(${name} PRIVATE cargoxx Catch2::Catch2WithMain)
-    catch_discover_tests(${name})
-endfunction()
-
-cargoxx_add_test(util_error)
-cargoxx_add_test(semver_satisfies)
-cargoxx_add_test(exec_run)
-cargoxx_add_test(manifest_parse)
-cargoxx_add_test(manifest_write)
-cargoxx_add_test(layout_discovery)
-cargoxx_add_test(lockfile_round_trip)
-cargoxx_add_test(linkdb_lookup)
-cargoxx_add_test(linkdb_overlay)
-cargoxx_add_test(codegen_flake)
-cargoxx_add_test(codegen_cmake)
-cargoxx_add_test(cmd_new)
-cargoxx_add_test(cmd_build)
-cargoxx_add_test(cmd_run)
-cargoxx_add_test(cmd_clean)
-cargoxx_add_test(cmd_add)
-cargoxx_add_test(cmd_remove)
-cargoxx_add_test(nixpkgs_probe_parse)
-cargoxx_add_test(nixpkgs_probe_live)
-cargoxx_add_test(nix_cmake_scan_parse)
-cargoxx_add_test(nix_cmake_scan_live)
-cargoxx_add_test(conan_probe_parse)
-cargoxx_add_test(conan_probe_live)
-cargoxx_add_test(vcpkg_probe_parse)
-cargoxx_add_test(vcpkg_probe_live)
-cargoxx_add_test(verify_link_unit)
-cargoxx_add_test(devbox_resolve_parse)
-cargoxx_add_test(devbox_resolve_live)
-cargoxx_add_test(nixpkgs_git_resolve)