Moonbase Skill

Use this when adding, building, or testing license activation / copy protection in a Pulp plugin or app with Moonbase, or when working under examples/moonbase-activation/.

Moonbase is a hosted licensing service. moonbase-cpp is a header-only, MIT-licensed C++17 client. Pulp consumes it via FetchContent (target moonbase::licensing) — no fork, no vendoring. Pulp owns only a registry entry, docs, this skill, and the reference example; upstream owns the SDK.

Load-bearing build settings (lead with these)

pulp add moonbase resolves the dependency and the link target, but it does not carry the two cache settings below. Set them before the dependency is made available:

set(MOONBASE_BUILD_TESTS    OFF CACHE BOOL "" FORCE)
set(MOONBASE_BUILD_EXAMPLES OFF CACHE BOOL "" FORCE)
set(MOONBASE_USE_CURL       OFF CACHE BOOL "" FORCE)  # supply your own transport

target_link_libraries(MyPlugin PRIVATE moonbase::licensing)

MOONBASE_USE_CURL=OFF makes the upstream INTERFACE target define MOONBASE_DISABLE_CURL_TRANSPORT for you and drops libcurl. Inject a transport instead — the example supplies one over Pulp's cpp-httplib/mbedTLS stack.

OpenSSL bolt-on (known upstream caveat)

Moonbase documents OpenSSL as a system requirement (its README expects OpenSSL::SSL/OpenSSL::Crypto findable on the system), and v3.3.0's CMake runs find_package(OpenSSL REQUIRED) and links it unconditionally, with no MOONBASE_CRYPTO_NATIVE CMake wiring. So OpenSSL must be present at configure time, and v1 simply uses the OpenSSL crypto backend (required + linked anyway) — the simplest, no-extra-wiring path. This is upstream's intended design, not a blocker and not a reason to fork. The example's CMake auto-discovers OpenSSL; per platform:

• macOS: brew install openssl@3 (/opt/homebrew/opt/openssl@3 on Apple silicon); pass -DOPENSSL_ROOT_DIR=$(brew --prefix openssl@3) if needed.
• Linux: apt install libssl-dev (or distro equivalent).
• Windows: vcpkg (vcpkg install openssl) or a system package, discoverable via the toolchain / OPENSSL_ROOT_DIR.

OS-native crypto is optional, not v1's default. MOONBASE_CRYPTO_NATIVE is a preprocessor macro (define it on the consuming target and link the platform crypto libraries) that switches RS256 to Security.framework / CNG / system libcrypto. Since OpenSSL is a documented Moonbase requirement and is linked regardless, native crypto does not let you drop OpenSSL — so it buys little here. The example uses the OpenSSL backend; don't bother with native for v1.

moonbase-pulp User-Agent contract

Set Moonbase's client_info so Moonbase can attribute Pulp-driven traffic:

options.client_info = "moonbase-pulp/<version> (GenerousCorp Pulp; <OS>)";

It is appended after moonbase-cpp/<ver> in the HTTP User-Agent:

User-Agent: moonbase-cpp/3.3.0 moonbase-pulp/1.0.0 (GenerousCorp Pulp; macOS)

The moonbase-pulp token mirrors Moonbase's moonbase-juce convention, so their client segmentation attributes Pulp traffic with no work on their side. The example wires it through a single named constant; document it so even a hand-rolled integration sets it. Recommend it, don't silently force it — it is the developer's HTTP client and field.

Audio-thread gating rule

The one hard real-time rule. The audio thread reads a single atomic; everything else runs off-thread:

// process() — audio thread, lock-free:
if (!licensed.load(std::memory_order_relaxed)) {
    buffer.clear();   // or bypass / reduced functionality
    return;
}

All Moonbase calls are non-realtime (rt_safe: false). Never call Moonbase, allocate, or block from process(). A non-audio controller owns network, storage, and revalidation and publishes only the std::atomic<bool> licensed.

UI convention

• Native by default, no WebView. The activation UI renders through Pulp's view/canvas stack. Online activation opens the system browser and the editor polls from the native controller (matching Moonbase's own reference flow). An embedded WebView is an optional later mode, not the default.
• Theme tokens, not a Moonbase palette. Build the panel from pulp::view::Theme tokens so it inherits the host plugin's look. Moonbase supplies licensing behavior, not the editor's visual identity.
• Two surfaces, one layout. build_activation_view() is a STATIC panel for a const controller (tests + the headless screenshot tool); ActivationPanel is the INTERACTIVE editor whose button drives the controller and which rebuilds on screen change. Both share the detail::lay_out_panel helpers, so the rich license-details rendering (name/email/product/type/expiry/seats) stays in one place.

Editor wiring (and the one reentrancy trap)

The live editor drives the controller from the view's frame clock (view.frame_clock()->subscribe([](float dt){...})): each tick calls controller.pump() (applies background revalidation), poll_once() ~1 s while in BrowserWait, and ActivationPanel::refresh_if_changed() to rebuild when the screen advances. Return false from the subscriber once the editor closes to auto-unsubscribe.

Never rebuild the view tree from inside a child's event handler. The action button's on_click must NOT call rebuild() — that destroys the very button whose click is still being dispatched (a use-after-free → SIGSEGV). Instead the handler only invokes the controller action + request_repaint(); the screen changed, so the next frame tick's refresh_if_changed() rebuilds safely once the event has unwound. This is why the action is deferred, not immediate.

Non-blocking startup (start_async / pump)

start_async() applies any stored license SYNCHRONOUSLY (the editor opens unlocked with no network wait) and re-validates online on a ONE-SHOT background thread. The worker only writes a mutex-guarded result slot + an atomic ready flag; screen_/license_ are touched solely on the UI thread (start_async/pump), so there is no data race on UI state and the audio thread still only reads licensed(). The controller joins the worker in its destructor. This is the HALO-style "synchronous-local-then-async-online" pattern — do not turn it into a continuous background poller (that reintroduces the UI-state race).

Click-free gate

Gate audio through a pulp::signal::SmoothedValue<float> (12 ms ramp set in prepare()), not a hard mute: gate_.set_target(licensed ? 1 : 0) then multiply each frame by gate_.next(). Before prepare() the ramp is one sample (an instant switch), so a unit test that never prepares still sees hard gating.

Loadable formats + screenshots

pulp_add_plugin(MoonbaseActivation FORMATS CLAP Standalone ...) builds a real loadable plugin + app; VST3/AU are appended when their developer-supplied SDKs are present. Each format target must also link moonbase::licensing + pulp-cpp-httplib (loop over MoonbaseActivation_<FMT>). The moonbase-activation-screenshots tool renders each screen headlessly via render_to_file(..., ScreenshotBackend::skia) — faithful text needs Skia in the build.

Controller scope

Keep the Pulp controller a thin router over upstream semantics. It owns UI state, background scheduling, generation-guarding of its own async callbacks, and the audio-thread atomic. It does not re-implement Moonbase's cross-process store locking, online-validation grace handling, or stale-write protection — lean on upstream's validate_token_online and file_license_store as-is.

Validate before shipping

• Registry: python3 tools/packages/validate_registry.py --check-licenses — the moonbase entry is clean (license MIT, FetchContent, target moonbase::licensing).
• Deps: python3 tools/deps/audit.py --strict — Moonbase must show DEPENDENCIES.md=yes NOTICE.md=yes licensing.md=yes.
• Transport test: assert the moonbase-pulp token actually appears on the wire (method/URL/headers/body round-trip against a local server).
• Gating test: with licensed=false, process() fades to silence; flipped to true, audio fades back to pass-through (assert the ramp is monotonic + settles, not just the steady state).
• Interactive test: simulate_click the action button → controller advances (e.g. Welcome → BrowserWait) → refresh_if_changed() rebuilds; assert no WebView node after interaction.
• Async test: start_async() with a stored license sets licensed() + the Details screen immediately; pump() in a loop never drops the license.
• UI proof: render the activation screens through the Pulp view tree (Skia); assert no WebView node on the default path.
• Loadable build: MoonbaseActivation_CLAP / _Standalone link and produce bundles; the screenshot tool writes faithful PNGs.
• No live network in CI — live activation stays a manual local check.

Pointers

• Reference plugin: examples/moonbase-activation/
• Developer guide: docs/guides/copyright-protection.md
• Registry entry: tools/packages/registry.json (moonbase)
• Upstream: https://github.com/Moonbase-sh/moonbase-cpp (pinned v3.3.0)