Apache-2.0 was the wrong declaration for two independent reasons. Enabling the `vst3` feature links vst3-sys, which is GPLv3-or-later by its own authors' choice — they describe their port as a derivative of Steinberg's SDK that "was not made in isolation", so the obligation holds regardless of any question about Steinberg's own rights. Gating the feature kept the default build clean, but plugins built from this template are intended to ship VST3, so GPL is where they land anyway. Declaring it up front is more honest than deferring the decision to every clone. Separately, parts of src/lib.rs derive from Robbert van der Helm's NIH-plug cookiecutter template and its `gain` example, both ISC. ISC's one condition is that its copyright and permission notice travel with all copies, and this repo carried neither — a compliance gap that existed regardless of the GPL question. ISC is GPL-compatible, so the notice is retained in a new NOTICE file rather than superseded. The `vst3` feature stays opt-in, but its rationale changes: it is no longer about licence compliance, only about not pulling a sizeable dependency into a CLAP-only build. The Cargo.toml comment said otherwise and would have misled the next reader. Also corrects the README's claim that you must "accept Steinberg's VST3 SDK licence". No SDK source is vendored or redistributed here, so there is nothing to accept at build time. The real constraint is vst3-sys's GPLv3, plus Steinberg's separate trademark in "VST" — a different regime from copyright that no source licence resolves. Copyright in the Irene <irene@novoyuuparosk.org> commits is held by the repository owner (an agent identity), so no third-party agreement was needed for this relicense. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01WHt4DykxXaQnyaJfyS8KCn
NIH-plug Template
Minimal scaffold for new NIH-plug audio plugins (Rust + CLAP/VST3 + egui).
Based on patterns from musiikki/codename-206.
Quick Start
# Clone this repo as your starting point
git clone http://192.168.2.199:3005/musiikki/nih-plug-template my-plugin
cd my-plugin
# Edit: src/lib.rs, Cargo.toml, bundler.toml — replace placeholder values
# See musiikki/codename-206 for a real-world example of how to fill these in
# Then verify the rename landed everywhere
sh check-branding.sh
Renaming
Branding is duplicated across Cargo.toml, bundler.toml, src/lib.rs and the docs,
and nothing makes those agree — so a half-finished rename builds a bundle under one name
while the docs and deploy script look for another.
check-branding.sh declares the identity once at the top and asserts every copy matches:
sh check-branding.sh # exit 0 = consistent, 1 = drift found
It covers the identity a host actually sees (package and bundle names, Plugin::NAME,
VENDOR, EMAIL, CLAP_ID, VST3_CLASS_ID, the descriptions) and the Rust type names
(MyPlugin, PluginParams) at every site they appear. Renaming the types is cosmetic —
no host ever sees them — but leaving MyPlugin in a shipped plugin is the kind of residue
that says nobody read the file. Leave them as-is and those checks simply stay green.
To rename: edit the canonical block at the top of the script, run it, and fix everything
it reports. The placeholder spellings are pre-seeded into its STALE list, and each one
arms itself as soon as you change the matching canonical value — so leftovers surface
without you having to track them. It also asserts VST3_CLASS_ID is exactly 16 bytes and
that CLAP_ID is reverse-DNS safe, both of which are otherwise a compile error or a
silent identity change between machines.
Checks for files the template doesn't ship (e.g. a deploy.ps1) report as skip and
start enforcing once you add them.
Build
# Install Rust via rustup: https://rustup.rs
# No VST3 SDK needed — NIH-plug bundles its own bindings.
# Build + bundle the CLAP (default)
cargo xtask bundle nih_plug_template --release
# Add the VST3 as well — see the licensing note below before you do this
cargo xtask bundle nih_plug_template --release --features vst3
Output: target/bundled/<name>.clap (and <name>.vst3 with --features vst3), where
<name> is the name set in bundler.toml — not the crate name. Out of the box that
means target/bundled/Plugin Name.clap.
On Linux the egui editor needs the GUI development headers:
sudo apt install pkg-config libgl-dev libx11-dev libxcursor-dev libxcb1-dev \
libxcb-icccm4-dev libxcb-dri2-0-dev libx11-xcb-dev libxkbcommon-dev libxkbcommon-x11-dev
Deploy
FL Studio
Build with --features vst3 first if you want the VST3 (see the licensing note below).
FL Studio scans C:\Program Files\Common Files\VST3 by default, ignores directory junctions
(so a symlinked bundle is invisible to its scanner), and caches failed scans.
- Copy the
.vst3bundle to a folder FL scans (e.g.C:\Program Files\Common Files\VST3). - Copy the
.clapbundle to a folder FL scans (e.g.C:\Program Files\Common Files\CLAP). - In FL Studio: Options → Manage plugins → tick "Rescan previously failed plugins" → Find installed plugins, then search for your plugin name (set in
bundler.toml).
Linux
# CLAP
cp -r "target/bundled/Plugin Name.clap" ~/.clap/
# VST3 (only exists if you built with --features vst3)
cp -r "target/bundled/Plugin Name.vst3" ~/.vst3/
# Or globally:
# sudo cp -r "target/bundled/Plugin Name.clap" /usr/lib/clap/
# sudo cp -r "target/bundled/Plugin Name.vst3" /usr/lib/vst3/
Project Structure
Cargo.toml # Package deps + the opt-in `vst3` feature — NIH-plug pinned to codename-206's rev
bundler.toml # Bundle name for `cargo xtask bundle`
src/lib.rs # Plugin skeleton — params, DSP, and egui editor, with one example gain param
xtask/ # Bundler xtask (cargo xtask bundle)
.cargo/config.toml # xtask alias
check-branding.sh # Asserts the plugin's identity strings agree everywhere (see Renaming)
.gitattributes # Pins *.sh to LF so Windows checkouts keep a valid shebang
License
GPL-3.0-or-later. See LICENSE for the terms and NOTICE for third-party attribution.
Plugins cloned from this template inherit GPL-3.0-or-later, because the template's own code is under it. If you need a permissive plugin, this is the wrong starting point — write the skeleton yourself against NIH-plug directly, which is ISC.
Parts of src/lib.rs derive from Robbert van der Helm's NIH-plug cookiecutter template and
gain example, both ISC. ISC is GPL-compatible, so that notice is retained in NOTICE
rather than superseded.
VST3 and Steinberg
vst3-sys, which nih_export_vst3!() needs, is GPLv3-or-later — chosen by its own authors,
who describe their port as a derivative of Steinberg's SDK that "was not made in isolation."
That obligation is what makes a distributed VST3 build GPL-licensed, and it holds regardless
of any question about Steinberg's own rights. Being GPL-3.0-or-later already, this template
satisfies it.
No Steinberg SDK source is vendored or redistributed here, so there is nothing to accept at build time. Separately from copyright, "VST" is a trademark of Steinberg Media Technologies GmbH; describing a distributed product as a VST plugin is governed by their trademark terms. If you intend to distribute commercially under that name, that is the part worth legal advice.
CLAP carries none of this — no GPL dependency and no trademark encumbrance.