aap-core v0.11.0, aap-lv2 v0.6.0, aap-juce v0.8.0 released

[atsushieno]

Today I have tagged v0.11.0 on aap-core, v0.6.0 on aap-lv2, and v0.8.0 on aap-juce repos. We are going to release UAPMD v0.5.0 to support AAP v0.11.0 as well.

If everything goes well, this version and the related stuff will be released as AAP v1.0 Preview ecosystem.

AAP v0.10.0 was released two months ago. It had a lot of eye-candy stuff with the advanced plugin UI support, but not a few core features were not functional and did not integrate well with plugin host (namely UAPMD). This AAP v0.11.0 brings in a lot of them really functional with the reworked architecture so that the entire AAP ecosystem becomes really useful.

I also published some screenrecordings of AAP in action. For example:

https://www.youtube.com/watch?v=Er2E2LjYmdw

... it uses a UAPMD project that was created by importing some SMF, assigned plugins, saved, and then (the demo starts) loaded and played.

This month I also had a session talk at ADC Japan 2026. The slides are uploaded to SpeakerDeck. If you cannot wait for ADC recordings, you can watch my (kind of) replay on YouTube.

Overview of the changes

• AAP v0.11.0 switches to the new gen.4 Protocol.
• Parameters, States, Presets, and GUI are all functional on UAPMD on Android. You can load UAPMD projects (involves State loading), add plugin instances, select any preset either on the plugin UI or on the host, then save the project (involves State saving).
• Parameter changes from host, GUI, or plugin itself, are now correctly reflected to the other parties on aaphostsample and UAPMD
• Loading states or presets also trigger parameter updates as expected, as well.
• Now you can build AAP hosts using (pseudo) CLAP API.
• AAP MidiDeviceServices now integrate MIDI-CI Property Exchange.

AudioPluginService gen.4 Protocol (Breaking Change)

We have made a lot of breaking ABI changes since the last version. That means, existing plugins and hosts for older versions are not usable with AAP v0.11.0 or later anymore. Technically, our AudioPluginService's android:name has changed to org.androidaudioplugin.AudioPluginService.V4 which gen. 3 hosts don't query and gen. 3 plugins don't advertise.

The actual ABI breakage is at the Binder API level (AIDL). There are changes in the fundamental extension and host extension messaging to become "asynchronous". With this change, extension functions such as States, Presets, and Parameters API got async-ified.

Host extension foundation got refresh implementation and similarly async-ified, but we don't have working host extension implementation yet (such as parameters metadata change notification).

We still haven't async-ified the extension API this time, but libandroidaudioplugin C++ API is async-ified as well. AAP-JUCE and UAPMD make use of this updated C++ API.

Fundamentals

AAP v0.11.0 realizes these features:

• Parameter changes by State loading are now notified to the host and they can be updated if host implements parameter updates. aaphostsample and UAPMD implement that. #177
• Overall parameter changes are now appropriately reflected on the plugin UI, which marks the entire GUI feature as done. #158
• We have moved sampleRate parameter from instantiation to prepare() so that changing the sample rate does not have to involve instance destruction and recreation (which is a technical debt from LV2 API). #163
  • We leave changing of sample rate unsupported in aap-lv2.
• Introduced Extensions BOM (bill of material). Instead of listing almost fixed list of <extension> elements, we can specify <extensions bom="0.12.0" /> in aap_metadata.xml. #186
• dynamic resizing of GUI is made possible. There was a lot of struggle with aap-juce-odin2 GUI.
• There was a lot of internal changes to not special-case standard extensions and really generalize our AAPXS foundation. In particular, now we control which extension functions can be transferred via realtime MIDI2 SysEx processes and which should go only via Binder.
  • These changes made various extension features work well with UAPMD and aaphostsample.
• We also formalized value semantics of parameters - we get and set "plain" numeric values.

MIDI-CI Property Exchange integration

We could finally integrate atsushieno/midicci on our Midi(Ump)DeviceServices. If a MIDI-CI client queries AllCtrlList, CtrlMapList, and ProgramList, they get responses from those AAP MIDI devices. You can actually build and run midicci-app from the repo to verify interoperability.

Support for CLAP hosting API

While it is not really tested a lot, we have a new module called aap-clap-hosting-helper that makes it possible to build AAP host using CLAP API. IF you write a CLAP host and get it running on Android, you can reuse your host code a lot. With this API, every AudioPluginService is enumerated as clap_entry_t.

AAP GUI extension is exposed as our own type.

There is an example host application that just lists installed "(pseudo) CLAP" plugins and shows its parameters and presets in CLAP manner.

Integration tests and androidaudioplugin-js-controller module

AAP repositories are split by nature, and thus testing its behavior has not been always practical. We finally created aap-integration-tests repository which is an AI-slop, testing foundation that downloads GitHub Actions artifacts for the registered repositories, runs multiple host apps, and performs automated testing on each host. On GitHub Actions we use Gradle Managed Device so far.

To make integration testing practically possible, we have introduced a new AAP host controller module based on QuickJS, just like we do on UAPMD. Coding AI agents can also connect to the JS controller over adb connection and send instructions.

Those integration test items are mostly added using coding AI agents and human languages.

Stability fixes

• Now we generate strict identifier for plugin instances and their GUI session IDs so that unrelated GUI won't be instantiated and shown up.
• Now we use Binder death recipients to flag that a plugin is dead, back to the host side so that host will not crash by attempt to use dead ones.
• We also make use of the Binder death notification to terminate async AAPXS requests.
• Introduced timeouts on asynchronous operations