# obs-streamer-tools-plugin Native OBS Studio source plugin that pulls streamer-tools camera feeds directly from LiveKit over WebRTC, replacing the current SRT/RTSP-via-VLC-or- Media-Source path for directors. Full design: `docs/superpowers/specs/2026-09-06-obs-camera-plugin-design.md` in the `streamer-tools` repo. ## Status **Release/distribution of built binaries is blocked pending owner sign-off.** This plugin statically/dynamically pulls in Google WebRTC and OpenH264 code through the LiveKit SDK — a real patent/royalty question (OpenH264/WebRTC) that only the project owner can decide. Nothing in this repo should be built into a package and handed out, posted, or attached to a public release until that sign-off happens. See `third_party/livekit/README.md` for the specifics of what is and is not currently known/shipped on the licensing side. (CI in `.gitea/workflows/build.yml` only builds, tests, and uploads CI-internal build artifacts — it does not create a Gitea Release or otherwise publish anything publicly. `.gitea/workflows/release.yml` is the mechanism that *would* publish a release, but it does not run automatically: it is gated on someone pushing a `v*` tag, which is the actual sign-off gate in practice — don't push one until the owner has actually signed off on C1. When it does run, it packages each platform's `build/package/` (or macOS's bundle output, once that lands) into a zip and creates a **draft** Gitea Release, whose generated release notes lead with the same C1 reminder as this section, so whoever opens the draft to publish it sees the open question again before doing so. Building that mechanism is not the same as clearing C1 — it still requires the same owner sign-off before a tag gets pushed.) The separate license-compatibility question — this repository's own top-level `LICENSE` was GPLv2 while the vendored LiveKit binaries are Apache-2.0, which are incompatible — is **resolved**: the project owner has relicensed this project's own first-party code to Apache-2.0, matching LiveKit. Everything in this repo is now Apache-2.0, so there is no remaining GPL/Apache incompatibility. The plugin is **functionally complete on Linux and verified end to end there** (module loads into real libobs, connects to a real LiveKit server through the real streamer-tools API shape, and pushes decoded frames into `obs_source_output_video`/`_audio`). It has **not been run in the OBS GUI on any platform.** macOS builds the real module in CI but its artifact is not yet loadable (see the macOS packaging gap under CI). **Windows CI is now green.** The run at `f27b1c0` is the first completed green Windows job on this repository: the from-source libobs bootstrap configures, builds and installs, `find_package(libobs)` resolves, all 6 CTest suites pass, and `build\package\bin\64bit\streamer-tools-camera.dll` (136,192 bytes) is staged next to `livekit.dll` and `livekit_ffi.dll` — read out of the job's own log body, not inferred from the job status. That also retires three previously-unproven items in one go: the `-A x64` argument fix, the PowerShell rewrite of the Windows steps, and the `add_subdirectory` patch for `OBS::w32-pthreads`. Windows is still **unverified in the OBS GUI**, exactly like the other two platforms. See "Where the Windows bootstrap got to" under CI below for the whole trace, and check current CI status rather than trusting this paragraph's age. See "What is verified, and how" below for exactly what has and has not been checked, and "Testing this by hand" for what a human still needs to do. ## Layout ``` cmake/LiveKitSDK.cmake - downloads + unpacks the pinned client-sdk-cpp release core/ - core library (C++17, no OBS dependency, headless-testable) include/stplugin/ core.h version + ConnectionConfig json.h small strict JSON reader http.h injectable HTTP client interface api_client.h the two /api/obs/:slug/* calls session_types.h media/state types + the pure session logic session.h LiveKitSession, the livekit::Room wrapper src/ http_curl.cpp libcurl backend (Linux/macOS) http_winhttp.cpp WinHTTP backend (Windows) tests/ dependency-free CTest suites obs-adapter/ - thin OBS glue (C++) src/plugin-main.cpp obs_source_info, properties UI, frame output data/locale/en-US.ini scripts/livekit-dev-room.py - mints tokens for the integration test third_party/livekit/ - redistribution notices for the LiveKit binaries .gitea/scripts/ - the actual per-platform build commands, shared by build.yml and release.yml .gitea/workflows/build.yml - 3-platform CI matrix (every push/PR; never publishes) .gitea/workflows/release.yml - packages + creates a draft Gitea Release (only on a `v*` tag push; see Status above) ``` ## How it works 1. The operator fills in the streamer-tools server URL, room slug and read key, and picks a camera from the dropdown. 2. The source's own worker thread calls `POST /api/obs/:slug/token?key=…` to mint a hidden, subscribe-only LiveKit token (identity `obs::` — a fresh nonce per mint, so two OBS installs watching the same room can never kick each other). 3. `LiveKitSession` connects `livekit::Room` to the returned `wsUrl`, waits for the chosen participant's `Source.Camera` video track (and their microphone), and reads decoded frames off `VideoStream`/`AudioStream`. 4. The adapter hands those straight to `obs_source_output_video` / `obs_source_output_audio`. Nothing on the OBS UI thread ever blocks on the network. The one deliberate exception is the "Refresh camera list" button, which the operator pressed and is waiting on; it uses a shortened 5s timeout. ### Design decisions worth knowing before changing this - **Frames come from `VideoStream::fromTrack` with our own reader threads, not from `Room::setOnVideoFrameCallback`.** The dispatcher API is keyed by (participant identity, track *name*), which is only knowable once the track is published — and disassembly of `liblivekit.so` 1.10.1 confirms that neither `Room::setOnVideoFrameCallback` nor the dispatcher's own version starts a reader for an already-subscribed track; they only record the registration. Registering at the only moment the name exists would therefore have silently produced no video. - **Every stream operation runs on one owned worker thread**, never on a LiveKit room event thread: `Room::disconnect()` from inside a delegate callback is documented to deadlock. - **`VideoStream::Options::capacity` is 3**, making the SDK queue a drop-oldest ring buffer. A stalled consumer can only fall three frames behind and then sees the *newest* frame, not a backlog — the structural answer to the stale-media bug that motivated this plugin. - **Video and audio are both timestamped with `os_gettime_ns()` at arrival.** The SDK gives video a WebRTC capture timestamp and audio none; mixing two epochs inside one OBS source would guarantee A/V drift. This relies on the SDK's jitter buffering having already aligned them — the assumption the design doc flags for verification on real hardware. **Still unverified.** - **WebRTC changes resolution mid-stream.** Observed directly in the integration test: the first frames after (re)subscribing arrive at a downscaled spatial layer before ramping to the published size. The adapter passes each frame's own geometry through, and logs geometry changes. ## Building Linux (the platform that is fully verified). `STPLUGIN_BOOTSTRAP_OBS=OFF` skips the macOS/Windows OBS-SDK bootstrap, which Linux does not need: ``` sudo apt-get install -y cmake ninja-build libobs-dev libcurl4-openssl-dev cmake -S . -B build -G Ninja -DCMAKE_BUILD_TYPE=Release -DSTPLUGIN_BOOTSTRAP_OBS=OFF cmake --build build ctest --test-dir build --output-on-failure ``` The configure step downloads the pinned `client-sdk-cpp` release (~13 MB) into `build/_deps/livekit-sdk`. Point `-DSTPLUGIN_LIVEKIT_SDK_DIR=` at a persistent directory to cache it across builds; `-DSTPLUGIN_LIVEKIT_SDK_VERSION` and `-DSTPLUGIN_LIVEKIT_SDK_TRIPLE` override the pin and the release triple. The build stages a runnable layout into `build/package/`: ``` build/package/bin/64bit/streamer-tools-camera.so (RPATH=$ORIGIN) build/package/bin/64bit/liblivekit.so build/package/bin/64bit/liblivekit_ffi.so build/package/data/locale/en-US.ini build/package/licenses/... ``` That is exactly the layout OBS searches on Linux and Windows — `/obs-studio/plugins//bin/64bit` plus a sibling `data/`, per `AddExtraModulePaths()` in obs-studio's `UI/window-basic-main.cpp` — so `build/package/` is a straight drop-in. The module resolves the LiveKit libraries from `$ORIGIN` (verified: `ldd` on the staged copy resolves both to `bin/64bit/`), not from the build tree. macOS is not this shape; see the macOS packaging gap under CI. ## Testing this by hand **Nobody has yet run this in the OBS GUI. That test is still outstanding on all three platforms.** To do it on Linux: ``` mkdir -p ~/.config/obs-studio/plugins/streamer-tools-camera cp -r build/package/bin build/package/data \ ~/.config/obs-studio/plugins/streamer-tools-camera/ obs ``` (That yields `.../streamer-tools-camera/bin/64bit/streamer-tools-camera.so` and `.../streamer-tools-camera/data/locale/en-US.ini`, which is what OBS looks for.) Then: Sources → `+` → "streamer-tools Camera" → fill in the server URL, room slug and read key from the room's settings page → "Refresh camera list" → pick a camera. Check `~/.config/obs-studio/logs/` for `[streamer-tools-camera] connected to …` and `[streamer-tools-camera] video frame WxH I420`. What to look for that automated testing could not answer: - Does video actually *appear*, right way up, right colours? - Is A/V sync acceptable? (see the timestamp caveat above) - What is the end-to-end latency versus the existing egress path? - Does a publisher restarting mid-show recover cleanly on screen? ### Running the LiveKit integration test `core/tests/test_integration_livekit` publishes a synthetic camera into a real room and subscribes to it through the wrapper. It skips unless `STPLUGIN_IT_*` is set: ``` livekit-server --dev --bind 127.0.0.1 & eval "$(python3 scripts/livekit-dev-room.py)" ctest --test-dir build -R test_integration_livekit --output-on-failure ``` ## What is verified, and how Verified on Ubuntu 24.04 (libobs 30.0.2, client-sdk-cpp 1.10.1, livekit-server 1.13.6 in dev mode): | Claim | How it was checked | |---|---| | The pinned LiveKit SDK links and is callable | `test_livekit_smoke`: `initialize()`/`shutdown()` round-trip, header version asserted equal to the CMake pin | | The JSON reader handles real and hostile input | `test_json`, 158 checks, including truncated bodies, HTML error pages, binary garbage, lone surrogates, and a depth-limit case | | The API client parses the real response shapes and every error branch | `test_api_client`, 127 checks, against a fake HTTP client **and** a real loopback HTTP server driving the actual platform backend | | A dead/stalled/garbage server cannot hang or crash the plugin | loopback cases: truncated JSON, connection closed with no reply, non-HTTP bytes, dead port, stalled server cut off by the client timeout | | Session state transitions, track selection, frame geometry | `test_session`, 81 checks, plus real `connect()` failures against the real SDK | | **Media actually flows** | `test_integration_livekit` against a real LiveKit server: 36 video frames + 323 audio frames, correct I420 geometry and plane pointers, publisher unpublish → `hasVideo()` false with **no further frames from the dead publisher**, republish → video resumes | | **The module loads into real libobs and pushes frames** | a headless libobs harness (`obs_startup` + `obs_reset_audio`/`obs_reset_video` + `obs_open_module`) driving the built module against a stand-in streamer-tools API in front of a real LiveKit server. Log: `connected to ws://… watching cam-test` then `video frame 640x360 I420`; the camera dropdown populated as `Test Camera` / `Dark Camera (offline)`; status `connected`; clean destroy and unload | | A wrong read key is reported, not silently swallowed | same harness with a bad key: status `unknown room slug, or the read key is wrong or has been rotated`, warning info type, retry with backoff, no crash | | Changing the selected camera reconnects cleanly | same harness: switch to a dark slot and back. Each switch mints a fresh `obs::` identity and reconnects; video returns; status stays `connected`; no crash, no stale frame | | Two sources in one OBS process | same harness with a second source added: both connect with distinct nonce identities, both receive frames, both tear down cleanly | **Not verified anywhere:** - The OBS GUI, on any platform. No human has looked at this in OBS. - macOS beyond "CI builds and links the real module and the core tests pass". Its artifact is a bare `.so` with a relative libobs install name and will not load in OBS.app — see the macOS packaging gap under CI. - Windows beyond "the core library and the WinHTTP backend compile and their tests pass", from runs predating the current fixes. The WinHTTP backend has never run against a real streamer-tools server, only against the loopback test server in `test_api_client`. - A/V sync and end-to-end latency against the existing egress path. - Behaviour against the real production streamer-tools server (only against a stand-in serving the same shapes). - Token expiry after an hour. Expiry is handled *reactively*: a fatal disconnect makes the worker mint a fresh token and reconnect. The design doc's "proactively refreshed before expiry" is **not** implemented — `client-sdk-cpp` 1.10.1 exposes no way to hand a live `Room` a new token. ## CI `.gitea/workflows/build.yml` runs on every push, matrixed across the three runners available to this repo under the `CyberCoveLLC` org. | Job | `runs-on` | Runner | State | |---|---|---|---| | `linux` | `ubuntu-24.04` | `localhost.localdomain` | **Green.** Builds the real adapter against Ubuntu's libobs-dev 30.0.2, runs all six test suites, uploads `build/package` as an artifact | | `macos` | `macos-latest` | `home-mac` (Global) | **Green.** Builds libobs 30.0.2 from source, then the real adapter; 6/6 tests; artifact uploaded. But see the macOS packaging gap below | | `windows` | `windows-latest` | `winvm-builder` (org-scoped) | **Failing, fix pushed and awaiting a completed run.** Every completed run so far has failed; the latest got as far as building libobs and stopped on an OBS-side `OBS::w32-pthreads` target that its own modern CMake path never defines. A bootstrap patch for that gap has been pushed but not yet confirmed by a green run; see below | The Linux job is pinned to `ubuntu-24.04` rather than `ubuntu-latest`: this instance's two Linux runners answer `ubuntu-latest` with different releases, and 22.04's `libobs-dev` is OBS 27 — a different API surface, and the LiveKit SDK's own `linux-x64` asset does not even link there (hence the `ubuntu-22.04` SDK triple; see `cmake/LiveKitSDK.cmake`). macOS and Windows use the `obsproject/obs-plugintemplate` buildspec bootstrap, trimmed to drop `qt6` (this plugin's properties UI is plain `obs_properties_*`), with `obs-studio.version` pinned to 30.0.2 — the same version Linux builds against, and deliberately low, because OBS rejects a module built against a newer libobs than the one running it. **Both jobs fall back to a core-library-only build if the bootstrap fails**, rather than going red, with a workflow `::warning::` and a "Show what was built" step that reports no module. That fallback exists because the bootstrap is the least verifiable part of this project — there is no way to exercise a macOS or Windows OBS build from the Linux development machine — and a permanently red CI teaches people to ignore CI. **Do not remove the warning:** a green job that quietly stopped building the plugin is worse than a red one. ### Where the macOS bootstrap actually got to Six CI iterations, each fixing a real failure visible in the logs: 1. Upstream's Xcode generator → `No CMAKE_C_COMPILER could be found` (the runner has the Command Line Tools, not Xcode). Switched to Ninja. 2. OBS's SDK version regex only matches a full-Xcode SDK path. Synthesised a `MacOSX.platform/Developer/SDKs/MacOSX.sdk` symlink to the same SDK. 3. The install walked into `UI/obs-frontend-api`, whose binary is deliberately never built. The install's exit code is now tolerated. 4. Restricting the install to `libobs/` fixed that but lost the per-configuration export file. 5. `xattr -r -d com.apple.quarantine` followed the SDK symlink into the read-only system SDK. Symlink moved to the build directory; the xattr step is no longer fatal. 6. `IMPORTED_LOCATION or IMPORTED_IMPLIB not set for imported target OBS::libobs configuration Release` — OBS 30.0.2 installs `libobsTargets.cmake` without the per-config file that carries the library path. The top-level `CMakeLists.txt` now detects a locationless `OBS::libobs` and points it at the framework the bootstrap just built. All six are confirmed fixed: the macOS job now downloads obs-deps and obs-studio, builds libobs from source, builds and links the real adapter, passes 6/6 tests, and uploads its artifact. `otool -L` on the result shows it linked against libobs and `@rpath/liblivekit.dylib`. ### macOS packaging gap (known, unfixed) **The macOS artifact will not load in OBS.app as it stands.** Two reasons, neither of which CI can catch, because CI only proves it compiles and links: 1. It is a bare `streamer-tools-camera.so`. OBS on macOS loads plugins as `.plugin` bundles (`Contents/MacOS/`, `Contents/Resources/`, an `Info.plist`), which is what obs-plugintemplate's `cmake/macos/helpers.cmake` builds and which this project deliberately did not vendor. 2. `otool -L` shows the libobs dependency recorded as the relative path `libobs/libobs.framework/Versions/A/libobs`, inherited from the from-source libobs's own install name. A real plugin needs `@rpath/libobs.framework/Versions/A/libobs` plus an `LC_RPATH` pointing at `OBS.app/Contents/Frameworks`. Fixing this means either vendoring the template's macOS bundle helpers or adding an `install_name_tool` pass and a bundle layout — bounded work, but work that has to be done and checked on an actual Mac. It is deliberately not attempted here rather than guessed at. ### Where the Windows bootstrap got to Windows is by far the slowest job — the `lukka/get-cmake` step alone takes 7-15 minutes on `winvm-builder`, and the runner serialises jobs, so a burst of pushes leaves a queue that takes an hour to drain. **The honest record, as it stood before `f27b1c0`: every completed Windows CI run on this branch had failed.** (`f27b1c0` is the one that finally went green — see "After the w32-pthreads target" at the end of this section. The history below is kept because each dead end in it is a real constraint someone will otherwise rediscover.) The first 7 failures were all at commits predating the `-A x64` fix below. The 8th, at `edb0c02` — the first commit that actually carries that fix — has since completed, and it is the informative one: **the `-A x64` fix worked, and Windows failed further along, on something else.** A later run (`58f4832`) then failed for an unrelated reason — its Windows steps still used `shell: bash`, which on this runner is WSL and cannot run as local system — so it never reached cmake at all and tells us nothing about the bootstrap. The PowerShell rewrite that fixes that is still queued and remains unproven. Do not read any fix below as "confirmed" beyond what is stated; check current CI status rather than trusting this paragraph's age. What `edb0c02` showed: obs-deps and Qt6 downloaded, CEF skipped, the OBS sub-configure ran for 53s and correctly reported "Plugin Support" and "User Interface" disabled — then failed at generate time: ``` CMake Error at libobs/cmake/os-windows.cmake:46 (target_link_libraries): Target "libobs" links to: OBS::w32-pthreads but the target was not found. ``` **That looks like a genuine hole in OBS 30.0.2's opt-in modern CMake path on Windows, not something this repo is doing wrong.** Traced at the 30.0.2 tag: - `libobs/cmake/os-windows.cmake` links `OBS::w32-pthreads`; - that target is defined only by `deps/w32-pthreads/CMakeLists.txt`, reached only through `deps/CMakeLists.txt`; - `deps/` is added only by the **legacy** branch of the top-level `CMakeLists.txt`. The modern branch — the one `-DOBS_CMAKE_VERSION=3.0.0` selects — adds `libobs`, `libobs-d3d11`, `libobs-winrt`, `libobs-opengl`, `plugins`, `test/test-input` and `UI`, never `deps`; - `libobs/CMakeLists.txt` adds only `deps/libcaption` and `deps/uthash`; - `plugins/CMakeLists.txt` returns immediately under `ENABLE_PLUGINS=OFF`, and does not add `deps/` even when enabled. macOS is unaffected because its libobs does not link w32-pthreads. At 30.0.2 the modern path was the *default* only on macOS (`if(CMAKE_HOST_SYSTEM_NAME MATCHES "(Darwin)" OR OBS_CMAKE_VERSION ...)`), which is consistent with the Windows side of it being under-exercised upstream. Deliberately **not** "fixed" by bumping the pin: 30.0.2, 30.1.2, 30.2.3, 31.0.3 and 31.1.1 were all checked, and every one still links `OBS::w32-pthreads` from `libobs/cmake/os-windows.cmake` while none of them add `deps/w32-pthreads` from `libobs/CMakeLists.txt`. A version bump is therefore not obviously the answer and needs checking rather than assuming. Option 1 (build `obs-frontend-api`, matching obs-plugintemplate's own CI, and accept the Qt dependency on Windows only) was investigated and **rejected**: `UI/obs-frontend-api/CMakeLists.txt` only links `OBS::libobs`, nothing else — it does not itself pull in `deps/w32-pthreads`. What actually satisfies the target upstream is that `UI/CMakeLists.txt` returns early when `ENABLE_UI=OFF`, *before* reaching `include(cmake/os-windows.cmake)` — the file that (via its own `if(NOT TARGET OBS::w32-pthreads)` guard) adds `deps/w32-pthreads`. Upstream's CI never sets `ENABLE_UI=OFF`, so that add-as-a-side-effect-of-Qt always happens for them. Building `obs-frontend-api` instead of `libobs` would not change any of that; the only way to get the same side effect is to stop passing `-DENABLE_UI:BOOL=OFF`, which is exactly the ~100 MB Qt6 download this bootstrap was trimmed to avoid (see the Windows `buildspec.cmake` comment) and buys this plugin nothing, since its properties UI is plain `obs_properties_*`. Went with Option 2 instead: `cmake/common/buildspec_common.cmake` now carries `_patch_obs_studio_w32_pthreads()`, called for `OS_WINDOWS` right before `_setup_obs_studio()`. It patches the freshly-extracted `libobs/CMakeLists.txt` to add the one missing subdirectory itself, using the exact same `if(NOT TARGET OBS::w32-pthreads)` guard `UI/cmake/os-windows.cmake` already relies on upstream: ```cmake if(OS_WINDOWS) if(NOT TARGET OBS::w32-pthreads) add_subdirectory("${CMAKE_SOURCE_DIR}/deps/w32-pthreads" "${CMAKE_BINARY_DIR}/deps/w32-pthreads") endif() include(cmake/os-windows.cmake) ... ``` It is idempotent (checks for `deps/w32-pthreads` already present in the file before patching, so re-running against a previously-patched extraction is a no-op) and fails loudly with `FATAL_ERROR` if the anchor text it expects to find is not there, rather than silently doing nothing on a future OBS version whose `libobs/CMakeLists.txt` has changed shape. Verified locally (this is a Linux sandbox, so only the CMake string-patching logic itself could be checked, not a real Windows configure/build): ran the same `string(FIND)` /`string(REPLACE)` sequence against the real `libobs/CMakeLists.txt` fetched from the obs-studio 30.0.2 tag, confirmed it produces the intended `if(OS_WINDOWS) / if(NOT TARGET ...) / add_subdirectory(...) / endif() / include(...)` block, and confirmed a second run against the already-patched file is a no-op. Whether this actually gets libobs through CMake generate and building on a real Windows runner is the thing the next CI run needs to prove — option 3 (dropping the from-source libobs on Windows for a prebuilt SDK) remains the fallback if it does not. Two bugs of its own were found; the first is now proven fixed by `edb0c02` getting past it, the second is still unproven: 1. Upstream passes `-A x64,version=` to the OBS sub-configure, and with a current CMake that `,version=` suffix reappears verbatim in the sub-build's `CMAKE_VS_PLATFORM_NAME` — which obs-studio's own dependency downloader uses as the architecture, sending it after `windows-deps-2023-11-03-x64,version=10.0.26100.0.zip`: ``` string sub-command JSON member 'hashes windows-x64,version=10.0.26100.0' not found Unable to download .../windows-deps-2023-11-03-x64,version=10.0.26100.0.zip ``` Plain `-A x64` now. **Confirmed fixed:** the `edb0c02` run got past this and downloaded `windows-deps-2023-11-03-x64.zip` correctly. 2. The Windows CI steps were originally written in bash (via `shell: bash`) and were rewritten in PowerShell. **The bash version is now proven broken** by the `58f4832` run: on `winvm-builder`, `bash` resolves to WSL, and WSL refuses to run under the service account the runner uses — ``` Running WSL as local system is not supported. Error code: Bash/WSL_E_LOCAL_SYSTEM_NOT_SUPPORTED ##[error]Process completed with exit code 1. ``` so the step died on the shell without ever invoking cmake. The PowerShell rewrite is therefore necessary, but **still unproven in the other direction** — no completed run has yet included it. Note this also means `58f4832`'s failure says nothing about the `w32-pthreads` blocker; that result comes from `edb0c02` alone. (Superseded by the next subsection: the `w32-pthreads` blocker described above *was* the next thing solved, and the `add_subdirectory` patch and the PowerShell rewrite are both now proven by a completed green run. What stands from this subsection is its reasoning — why `ENABLE_UI=OFF` exposes the gap, and why re-enabling Qt or bumping the OBS pin is not the answer.) ### After the w32-pthreads target: the w32-pthreads *package* The `add_subdirectory(deps/w32-pthreads)` patch above did its job — the `edb0c02`-era generate error is gone, obs-studio 30.0.2 configures, builds `w32-pthreads.dll` and `obs.dll`, and installs. Two further Windows-only blockers then surfaced behind it, both the same underlying upstream mismatch and neither one a defect in this repo: 1. **`find_package(libobs)` could not locate the package it had just installed.** obs-studio's `cmake/windows/defaults.cmake` sets `OBS_CMAKE_DESTINATION=cmake`, and `target_export()` installs each package to `/${OBS_CMAKE_DESTINATION}//` — i.e. `.deps/cmake/libobs/`. That is not one of CMake's Config-mode search suffixes (`/cmake/` is, but only for a config file sitting *directly* in it; `/*/cmake/` is, but the `` directory has to come first). Fixed in `79de5e8f` by setting `libobs_DIR` explicitly; the long comment above that block in `CMakeLists.txt` has the full reasoning. 2. **…and then `libobsConfig.cmake` could not locate `w32-pthreads` for exactly the same reason.** `libobs/cmake/os-windows.cmake` links `PUBLIC OBS::w32-pthreads`, so upstream's `libobsConfig.cmake.in` carries a hard `find_dependency(w32-pthreads REQUIRED)` under `if(MSVC)`. Once fix 1 finally got that config file loaded, the dependency lookup inside it failed and killed the configure: ``` By not providing "Findw32-pthreads.cmake" in CMAKE_MODULE_PATH this project has asked CMake to find a package configuration file provided by "w32-pthreads", but CMake did not find one. .deps/cmake/libobs/libobsConfig.cmake:30 (find_dependency) ``` **This is not a missing export**, which was the first hypothesis and is worth recording as wrong: `deps/w32-pthreads/CMakeLists.txt` ends with `target_export(w32-pthreads)`, the same helper `libobs` itself uses, so it does emit `install(TARGETS … EXPORT w32-pthreadsTargets)`, `install(EXPORT … NAMESPACE OBS::)` and a generated `w32-pthreadsConfig.cmake`, all `COMPONENT Development`. Two independent arguments say those rules ran: CMake hard-errors at generate time if an exported target links a target that is in no export set at all (and OBS's generate step succeeded), and this repo's patch adds `deps/w32-pthreads` from `libobs/CMakeLists.txt`, making it part of the `libobs` subtree — which installs *before* the tolerated `UI/obs-frontend-api` install error aborts the rest. The package really is at `.deps/cmake/w32-pthreads/`; `find_package` was simply never going to look there. So the fix is the same one-liner as for `libobs`, and it is literally what CMake's own error message suggests: set `w32-pthreads_DIR` before the `find_package(libobs)` call that transitively triggers the `find_dependency`. Both `_DIR` blocks now sit next to each other in `CMakeLists.txt`. Behind that sits `cmake/windows/find-fallback/Findw32-pthreads.cmake`, used only if that export is genuinely absent from `.deps/`. It rebuilds `OBS::w32-pthreads` by hand from the bootstrap's own artifacts. It deliberately does *not* live in `cmake/windows/`, which `cmake/common/osconfig.cmake` already puts on `CMAKE_MODULE_PATH` for every Windows configure — a find module there would shadow OBS's real exported package on every build, since `find_package` tries MODULE mode before CONFIG mode. `CMakeLists.txt` appends the `find-fallback/` directory to `CMAKE_MODULE_PATH` only after it has established the real export is missing, and logs what *is* under `.deps/cmake/` when it does, so a future failure of this shape is answered by the CI log rather than by another run. Note this package is load-bearing for more than the dependency check: `libobs/util/threading.h` does `#include `, and on Windows that header only exists because `target_export(w32-pthreads)` installs `pthread.h`/`sched.h` as `PUBLIC_HEADER` into `.deps/include/`. Verified before pushing, on Linux, since this is a Linux sandbox: a reconstruction of the exact failure — a stub `libobsConfig.cmake` containing `find_dependency(w32-pthreads REQUIRED)`, reached through `libobs_DIR`, with the package installed at `.deps/cmake/w32-pthreads/` — reproduces the CI error without the `w32-pthreads_DIR` block and passes with it; and the fallback find module was exercised separately by deleting that package, with `find_package` resolving through MODULE mode to it instead. A full Linux configure of this repo is unchanged (both blocks are inside `if(OS_WINDOWS)`, and the upstream `find_dependency` is inside `if(MSVC)`, so macOS and Linux are pure no-ops). **Confirmed on the real runner.** The Windows job for `f27b1c0` completed green, and its log body — not just its status — shows the whole chain: ``` -- w32-pthreads_DIR not set; libobsConfig.cmake's find_dependency(w32-pthreads REQUIRED) hits the same OBS_CMAKE_DESTINATION=cmake search-suffix problem as libobs itself, so pointing it directly at the from-source install: ...\.deps\cmake\w32-pthreads -- libobs found (...\.deps\cmake\libobs) -- building OBS adapter module streamer-tools-camera.vcxproj -> ...\build\obs-adapter\Release\streamer-tools-camera.dll 100% tests passed out of 6 Directory: ...\build\package\bin\64bit -a---- 3078656 livekit.dll -a---- 25008640 livekit_ffi.dll -a---- 136192 streamer-tools-camera.dll ``` Note which branch that log took: the `w32-pthreads_DIR` message means the package config really was sitting at `.deps/cmake/w32-pthreads/` all along and the fallback find module was never loaded. The export was never missing — only unfindable. Linux and macOS were green in the same run, confirming the no-op. The one piece of noise left in that log is the tolerated `UI/obs-frontend-api/cmake_install.cmake` error, which now repeats once per CMake re-configure because Visual Studio's `ZERO_CHECK` target re-runs the bootstrap during the build. It is cosmetic and pre-dates this change, but it makes the Windows log harder to read than it should be.