add-conan-recipe

Add a Conan recipe

This skill scaffolds a Conan 2.x recipe under recipes/<name>/all/, validates it on Windows and Linux, and publishes it (recipe-only by default) to the endstone Cloudsmith remote. The layout mirrors conan-center-index so the recipe could be upstreamed later with minimal change.

Execute steps in order. STOP points wait for user input.

Inputs to collect up front

Before scaffolding, you need:

1. Package name (lowercase, kebab-case) and version (e.g. funchook / 1.1.3).
2. Source tarball URL. Prefer the GitHub release archive (https://github.com/<owner>/<repo>/archive/refs/tags/v<version>.tar.gz). If upstream uses submodules, you'll need a separate URL per submodule plus its pinned commit SHA (see Step 2.b).
3. Build system (CMake is the only one this skill handles cleanly; if it's autotools/meson/Make, stop and tell the user this skill assumes CMake — they may want to extend it).
4. License SPDX identifier — read the upstream LICENSE file.
5. Whether the user wants to upload after local validation. Default: recipe-only upload to endstone remote.

If any of these are unclear, ask once with AskUserQuestion before scaffolding.

---

Step 1 - directory layout

Create the folder tree:

recipes/<name>/
├── config.yml
└── all/
    ├── conandata.yml
    ├── conanfile.py
    ├── patches/                  # optional, only if upstream needs patching
    │   └── <version>-<short>.patch
    └── test_package/
        ├── CMakeLists.txt
        ├── conanfile.py
        └── test_package.<c|cpp>

config.yml maps versions to their recipe folder:

versions:
  "<version>":
    folder: all

---

Step 2 - sources and sha256

2.a Single tarball

Download the tarball to a scratch location and hash it:

mkdir -p build/sha-tmp
curl -sL -o build/sha-tmp/src.tar.gz "<URL>"
sha256sum build/sha-tmp/src.tar.gz

Write recipes/<name>/all/conandata.yml:

sources:
  "<version>":
    url: "<URL>"
    sha256: "<HASH>"

2.b Tarball + submodule(s)

GitHub release archives don't include git submodules. If git ls-tree HEAD <submodule-path> on the upstream repo shows a commit SHA, download the submodule's archive at that exact commit:

https://github.com/<owner>/<repo>/archive/<sha>.tar.gz

Hash it the same way. The conandata.yml then names each source so the recipe's source() can unpack them to the right relative paths:

sources:
  "<version>":
    main:
      url: "..."
      sha256: "..."
    # one entry per submodule, named after the submodule's path
    <submodule>:
      url: "..."
      sha256: "..."

In source(), use get(..., destination=os.path.join(self.source_folder, "<submodule>")) to land it where upstream's CMakeLists expects.

---

Step 3 - scaffold conanfile.py

Use the funchook recipe (recipes/funchook/all/conanfile.py) as the template. Key elements that almost always apply:

• name, description, license, url=<our project URL>, homepage=<upstream URL>, topics, package_type = "library".
• exports_sources = "patches/*" if you added patches.
• Settings: os, arch, compiler, build_type. Options: at minimum shared and fPIC (delete fPIC on Windows in config_options). Add upstream feature options as needed.
• configure(): rm_safe("compiler.cppstd") / rm_safe("compiler.libcxx") if it's a pure C library — otherwise package_id carries spurious C++ fields.
• requirements(): only conan deps. Anything bundled in the upstream source (submodules, downloaded-at-configure) should be handled in source() / package(), not requires.
• validate(): reject unsupported arch/OS with ConanInvalidConfiguration.
• source(): get(self, **self.conan_data["sources"][self.version], ...). If there are patches, call apply_conandata_patches(self) after get().
• layout(): cmake_layout(self, src_folder="src").
• generate(): CMakeToolchain + CMakeDeps. Set the upstream's cache variables to disable tests, force install on, pick install dirs.
• build(): standard cmake.configure() + cmake.build().
• package(): cmake.install(), copy LICENSE to licenses/, rmdir(self, "<package>/lib/cmake") etc. for cleanup. If upstream doesn't install a bundled static dep, copy it from build_folder by pattern.
• package_info(): declare cpp_info.libs, cmake_file_name, cmake_target_name. On Windows add system_libs (psapi, dbghelp, etc.) per upstream's link line. If consumed-as-static would leave unresolved symbols from a conan dep, set cpp_info.requires = ["<dep>::<dep>"].

If upstream's CMakeLists downloads a dep at configure time (e.g. FetchContent, ExternalProject_Add), prefer patching it to call find_package first and fall back to the bundled path. See recipes/funchook/all/patches/1.1.3-external-capstone.patch for the short-circuit pattern.

---

Step 4 - scaffold test_package

Three files:

• test_package/conanfile.py — minimal, mirrors funchook's. Sets test_type = "explicit", requires self.tested_reference_str, runs the built executable via self.run(exe, env="conanrun") inside can_run(self).
• test_package/CMakeLists.txt — find_package(<name> CONFIG REQUIRED), link against <name>::<name>.
• test_package/test_package.<c|cpp> — should exercise at least one symbol end-to-end so a successful exit means the package actually works, not just that linking succeeded. Watch for compiler inlining tripping up function hooking / pointer comparisons — mark relevant functions NOINLINE and use volatile if needed (see funchook's test_package).

STOP if you can't think of a meaningful end-to-end test. Ask the user for a snippet that exercises the library's main entrypoint.

---

Step 5 - local validation (Windows)

Run from project root with cmake on PATH:

$env:PATH = "C:\Program Files\Microsoft Visual Studio\2022\Community\Common7\IDE\CommonExtensions\Microsoft\CMake\CMake\bin;C:\Program Files\Microsoft Visual Studio\2022\Community\Common7\IDE\CommonExtensions\Microsoft\CMake\Ninja;$env:PATH"
conan create recipes/<name>/all --version=<version> -pr default --build=missing

If the recipe has options, test the non-default value too:

conan create recipes/<name>/all --version=<version> -pr default --build=missing -o '<name>/*:<opt>=<value>'

Iterate until Testing the package: Executing test prints the expected output. Common failure modes:

• Library '<name>-static' not found in package → upstream's OUTPUT_NAME differs from the recipe's cpp_info.libs. Inspect the installed package folder (.conan2/p/b/<name>*/p/lib) and update.
• Unresolved symbols → upstream installs the main lib but not a bundled dep; either copy the bundled lib in package() or patch upstream to use find_package.
• Test executable crashes with no useful output → ABI mismatch between separate builds of the same lib (classic when patching a find_package short-circuit but the conan dep isn't actually in requires). Check find_package(<dep> CONFIG QUIET) actually succeeds — QUIET hides the miss.

---

Step 6 - Linux validation in a container

ubuntu:20.04 gives glibc 2.31, which is roughly the floor Endstone targets:

docker run --rm -v "<absolute project path>:/work" ubuntu:20.04 bash -c '
export DEBIAN_FRONTEND=noninteractive
apt-get update -qq >/dev/null
apt-get install -qq -y --no-install-recommends build-essential ninja-build python3 python3-pip ca-certificates >/dev/null
pip3 install --quiet --no-input "cmake>=3.29" "conan>=2.0"
export PATH=/usr/local/bin:$PATH HOME=/work/.linux-home
conan profile detect --force >/dev/null 2>&1 || true
conan create /work/recipes/<name>/all --version=<version> --build=missing 2>&1 | grep -E "<test-success-marker>|ERROR|Built target"
'

After the run, delete the throwaway cache: rm -rf .linux-home.

Replace <test-success-marker> with a string the test_package prints on success (e.g. hooked add for funchook).

---

Step 7 - upload to Cloudsmith

STOP before uploading. Confirm with the user the upload scope:

• Recipe only (default): --only-recipe. Consumers build binaries locally on first install. Negligible Cloudsmith storage cost.
• Recipe + binaries: drop --only-recipe. Each package_id × option combination uploaded contributes real storage. Only do this when CI is going to need the binaries.

The Cloudsmith remote is named endstone in .conan2/remotes.json. Auth for upload requires HTTP Basic Auth with a personal Cloudsmith API key (entitlement tokens are read-only). The user must run conan remote login -p <api-key> endstone <cloudsmith-username> themselves in their own shell — don't ask them to paste the key into chat.

Once authenticated:

conan upload "<name>/<version>" --only-recipe -r=endstone -c

Verify:

conan list "<name>/*" -r=endstone

Cloudsmith has a brief post-sync indexing step (~30s); if conan list returns empty immediately after upload, wait and retry. The package appearing on Cloudsmith's web UI doesn't always mean conan list sees it yet.

For an end-to-end sanity check, blow away the local cache and re-pull:

conan remove "<name>/*" -c
conan install --requires=<name>/<version> -r=endstone --build=missing

---

Step 8 - wire endstone to consume it (optional)

If the goal was to replace a FetchContent or to add a new dep, then:

1. Add self.requires("<name>/<version>") to the project root conanfile.py.
2. Add find_package(<name> CONFIG REQUIRED) in the consuming src/.../CMakeLists.txt (typically src/endstone/runtime/CMakeLists.txt for hook-related deps).
3. Update target_link_libraries(...) to use <name>::<name> (most likely already named this way if you replaced a FetchContent alias).
4. Delete the old third_party/<name>/ folder and its add_subdirectory(<name>) line in third_party/CMakeLists.txt.
5. Confirm conan install . --build=missing -s compiler.cppstd=20 -c tools.cmake.cmaketoolchain:generator=Ninja ... succeeds.

The endstone Cloudsmith remote is already in tracked .conan2/remotes.json; devs cloning the repo will resolve the dep without any setup beyond pip install conan and conan profile detect.

---

Step 9 - commit

Stage only:

• recipes/<name>/ (the recipe folder)
• .conan2/remotes.json if you added a new remote
• conanfile.py, the CMakeLists changes, and any deleted third_party/ files if Step 8 was done
• README badge / CONTRIBUTING edits if applicable

Do not stage test_package build artifacts (recipes/.gitignore already excludes **/test_package/build/ and CMakeUserPresets.json). Leave the project's pre-existing untracked files alone.

Commit style matches the repo's conventional-commit history:

build: add <name> conan recipe

Body: one short paragraph explaining what the recipe wraps + which platforms were validated, then a bullet list of notable recipe quirks (bundled deps, patches, non-default cpp_info).

Never add a Co-Authored-By line for Claude.