Comparison with JUCE, nih-plug, iPlug2 and DPF
This page says what APF is for, and what it is not. It is written from the projects’ own descriptions as read on 2026-10-28; check their pages before deciding, they move.
What APF is for
APF’s job is narrow: ship one plugin, written in Rust, to every common consumer format, with a web page as its web view, with sessions, presets and host automation that restore correctly, and with MIT licences all the way down. The parts that decide whether a plugin feels finished are built in and tested:
- a web view as a first-class feature:
data-parambindings, MIDI learn, a preset bar, a controller channel for the plugin’s own requests, a resizable window, and the same page in CLAP, VST3, AUv2, AUv3 and the standalone app; - state: host sessions, factory and user presets, and plugin-defined state saved together, with the wrappers’ restore bugs fixed and covered by validators;
- the real-time rule (no allocation in
process) checked in every example by a counting allocator; - hot reload on macOS: a new build swaps into the running host in every format, with its state and window kept, checked in Logic Pro (Hot reload);
- MIT code and permissively licensed dependencies throughout.
What APF lacks
Said plainly, so you do not find out later:
- Linux. It is designed for but not built or tested. macOS (Apple silicon) and Windows (x64) are what is tested.
- AAX and LV2. (VST2 is not offered either.) Other frameworks list them; APF’s build does not.
- A DSP library.
apf::dsphas the basics (oscillators, an LFO, two filters, an envelope, a delay line, smoothing). There is no reverb, FFT, oversampling or sample playback. - Native widgets. The web view is a web page. If you want a native or GPU-drawn UI toolkit,
APF’s web view is not it (a Rust
Viewtrait exists, but there is nothing bundled for it). - An ecosystem. Few users, few tutorials besides this book, no plugin templates from the community, a young codebase (pre-1.0, one author so far).
- Hosts beyond Logic Pro and REAPER are not yet verified; see Hosts and formats.
Others, as their own pages describe them
| Project | Language | What its page says (2026-10-28) |
|---|---|---|
| JUCE | C++ | Version 8 offers WebView UIs (WebBrowserComponent with a C++/JavaScript bridge and parameter binding; WebView2 on Windows). A far larger ecosystem than APF’s. |
| iPlug2 | C++ | Supports a UI that is a full web view (IWebViewEditorDelegate); its own wiki warns of challenges. |
| nih-plug | Rust | Web views exist only as third-party experimental crates (for example httnn/nih-plug-webview, whose README says work in progress, tested on macOS). |
| nice-plug | Rust | VST3 and CLAP; GUI adapters for egui and iced (Slint in progress, Vizia third-party). |
| coupler | Rust | VST3 and CLAP; early in development, little documentation. |
| truce | Rust | CLAP, VST3, AU v2/v3, AAX, LV2 and VST2 (some opt-in) on macOS, Windows and Linux; built-in widgets, egui, iced, Slint and Vizia. More formats and platforms than APF. Experimental hot reload of DSP and its built-in GUI (its page, read 2026-10-30). |
| beamer | Rust | MIT; built around a web UI (beamer-webview on WKWebView), AU and VST3; macOS only so far, Windows in progress. |
| DPF | C++ | Not covered here: not checked for this book. |
What follows from that: a web UI inside a plugin is not unique to APF. JUCE 8 and iPlug2 have one, Beamer (Rust, MIT) is built around one on macOS, and other Rust projects are working on it. Choose APF if you want Rust, a web view as the normal way to build the interface, the five formats it builds on macOS and Windows, and MIT end to end. Choose another project if you need Linux, AAX or LV2 today, a native widget toolkit, a large DSP library, or a big community to lean on.
Licences
APF is MIT. Its dependencies are MIT, Apache-2.0, Zlib, BSD-3-Clause or Unicode-3.0 (the full list). The VST3 SDK is MIT since version 3.8. APF never requests AAX from the wrapper build, and uses no GPL or LGPL code. nih-plug was studied for ideas; no code was taken from it.