Merge branch 'feat/branding-checker-structural-names'

Extend the branding checker over descriptions and Rust type names, and fix
two bugs the tests for it exposed: a stale scan that silently passed
outside a git checkout, and a TODO count that broke once it reached zero.

.gitattributes

@@ -0,0 +1,4 @@
+# Shell scripts must keep LF endings. core.autocrlf=true on Windows would
+# otherwise check them out CRLF, which a strict POSIX sh (dash, CI containers)
+# rejects at the shebang.
+*.sh text eol=lf

Cargo.toml

@@ -10,6 +10,14 @@ license = "Apache-2.0"
 [workspace]
 members = ["xtask"]
 
+[features]
+# CLAP only by default. NIH-plug's VST3 bindings (vst3-sys) are GPLv3, so linking
+# them makes the resulting binary GPLv3 regardless of what this package declares.
+# Opt in explicitly — and relicense this crate — if you intend to ship a VST3:
+#   cargo xtask bundle nih_plug_template --release --features vst3
+default = []
+vst3 = ["nih_plug/vst3"]
+
 [lib]
 # `cdylib` is the plugin binary; `lib` (rlib) lets `cargo test` link the unit tests.
 crate-type = ["cdylib", "lib"]
@@ -17,7 +25,8 @@ crate-type = ["cdylib", "lib"]
 [dependencies]
 # Pinned to the same commit as musiikki/codename-206.
 # Update the `rev` when you want to update NIH-plug.
-nih_plug = { git = "https://github.com/robbert-vdh/nih-plug.git", rev = "f36931f7af4646065488a9845d8f8c2f95252c23", features = ["assert_process_allocs"] }
+# `default-features = false` drops nih_plug's default `vst3` feature; see [features] above.
+nih_plug = { git = "https://github.com/robbert-vdh/nih-plug.git", rev = "f36931f7af4646065488a9845d8f8c2f95252c23", default-features = false, features = ["assert_process_allocs"] }
 nih_plug_egui = { git = "https://github.com/robbert-vdh/nih-plug.git", rev = "f36931f7af4646065488a9845d8f8c2f95252c23" }
 
 [profile.release]

README.md

@@ -13,24 +13,69 @@ 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:
+
+```bash
+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
 
 ```bash
 # Install Rust via rustup: https://rustup.rs
 # No VST3 SDK needed — NIH-plug bundles its own bindings.
 
-# Build + bundle the VST3 and CLAP
+# 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/nih_plug_template.vst3` and `nih_plug_template.clap`
+**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:
+
+```bash
+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.
 
@@ -41,25 +86,27 @@ FL Studio scans `C:\Program Files\Common Files\VST3` by default, **ignores direc
 ### Linux
 
 ```bash
-# VST3
-cp target/bundled/nih_plug_template.vst3 ~/.vst3/
-
 # CLAP
-cp target/bundled/nih_plug_template.clap ~/.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 target/bundled/nih_plug_template.vst3 /usr/lib/vst3/
-# sudo cp target/bundled/nih_plug_template.clap /usr/lib/clap/
+# 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 — NIH-plug pinned to codename-206's rev
+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 — fill in params, DSP, editor
+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
@@ -68,6 +115,16 @@ Apache-2.0
 
 ## VST3 Licensing Note
 
-You must accept Steinberg's VST3 SDK licence before distributing VST3 binaries.
-NIH-plug's VST3 bindings are GPLv3; if you distribute, the plugin must also be GPLv3
-(or you need a commercial Steinberg licence). CLAP has no such restriction.
+NIH-plug's VST3 bindings (`vst3-sys`) are GPLv3. Linking them makes the resulting binary
+GPLv3 regardless of what `Cargo.toml` declares, so **VST3 is behind an opt-in `vst3` feature
+and this template builds CLAP only by default.** That keeps the default build consistent with
+the Apache-2.0 licence in `Cargo.toml`/`LICENSE`.
+
+If you want to ship a VST3:
+
+1. Build with `--features vst3`.
+2. Relicense your plugin as GPLv3 (or obtain a commercial Steinberg licence) and update
+   `Cargo.toml`, `LICENSE`, and the SPDX headers in `src/`.
+3. Accept Steinberg's VST3 SDK licence.
+
+CLAP has no such restriction.

bundler.toml

@@ -1,7 +1,7 @@
 # Metadata for NIH-plug's `cargo xtask bundle <package>` bundler.
 #
 # [package_name]
-# name = "Human Readable Plugin Name"  # defaults to <package_name>
+# name = "Human Readable Bundle Name"  # defaults to <package_name>
 
 [nih_plug_template]
 name = "Plugin Name"

check-branding.sh

@@ -0,0 +1,207 @@
+#!/bin/sh
+# check-branding.sh - verify the plugin's branding/identity strings agree everywhere.
+#
+# Plugin branding is duplicated across the build manifest, the bundler manifest,
+# the source, the docs and (once you add one) the deploy script. Nothing makes
+# them agree, so a rename drifts silently: the bundle builds under one name and
+# the deploy script looks for another. This asserts they match, and that the
+# identity constants are legal.
+#
+# In a template this matters more than usual: renaming is the first thing you do
+# with this repo, and it touches every file below. Run this immediately after,
+# and the STALE machinery will list whatever you missed.
+#
+# Usage: sh check-branding.sh          (exit 0 = consistent, 1 = drift found)
+#
+# ---------------------------------------------------------------------------
+# CANONICAL IDENTITY - the single source of truth. Edit these to rename, then
+# run this script; every failure it prints is a place still holding the old name.
+# ---------------------------------------------------------------------------
+
+PKG="nih_plug_template"                     # Cargo package name == bundler.toml table key
+DISPLAY="Plugin Name"                       # bundle name -> "<DISPLAY>.vst3" / "<DISPLAY>.clap"
+PLUGIN_NAME="Plugin Name"                   # Plugin::NAME - what the DAW displays
+VENDOR="Your Name"                          # Plugin::VENDOR
+EMAIL="your@email.com"                      # Plugin::EMAIL
+HOMEPAGE="https://github.com/YOUR-USERNAME/YOUR-PLUGIN-NAME"  # Cargo homepage -> Plugin::URL
+CLAP_ID="com.your-domain.plugin-name"       # CLAP_ID - stable plugin identity
+VST3_CLASS_ID="Unique16CharId!!"            # VST3_CLASS_ID - stable identity, MUST be 16 bytes
+DESCRIPTION="A minimal NIH-plug audio plugin"     # Cargo package description
+CLAP_DESCRIPTION="Your plugin description"        # CLAP_DESCRIPTION - shown in some host browsers
+
+# Rust type names. These never reach a host, so renaming them is cosmetic - but
+# leaving "MyPlugin" in a shipped plugin is the sort of residue that says nobody
+# read the file. Change these to make the checks below enforce your own names;
+# leave them alone and they simply stay green.
+STRUCT="MyPlugin"                           # the Plugin impl target
+PARAMS_STRUCT="PluginParams"                # the Params impl target
+
+# Spellings that must no longer appear anywhere in tracked files. Seeded with
+# this template's own placeholders, so that renaming is self-checking: each entry
+# is skipped while it is still one of the canonical values above, and becomes a
+# live check the moment you change that value. Add your own old names here after
+# a later rename.
+STALE="nih_plug_template
+MyPlugin
+PluginParams
+A minimal NIH-plug audio plugin
+Your plugin description
+Plugin Name
+Your Name
+your@email.com
+com.your-domain.plugin-name
+Unique16CharId!!
+YOUR-USERNAME
+YOUR-PLUGIN-NAME
+your-domain"
+
+set -u
+cd "$(dirname "$0")" || exit 1
+
+pass=0; fail=0; skip=0
+ok()   { pass=$((pass+1)); printf '  ok    %s\n' "$1"; }
+bad()  { fail=$((fail+1)); printf '  FAIL  %s\n' "$1"; [ $# -gt 1 ] && printf '        %s\n' "$2"; return 0; }
+note() { skip=$((skip+1)); printf '  skip  %s\n' "$1"; }
+# Reported for awareness only - never counted, never fails the run.
+info() { printf '  --    %s\n' "$1"; }
+
+# has FILE PATTERN -> fixed-string search
+has() { grep -qF "$2" "$1" 2>/dev/null; }
+
+check() { # check LABEL FILE LITERAL
+  if [ ! -f "$2" ]; then bad "$1" "missing file: $2"; return; fi
+  if has "$2" "$3"; then ok "$1"; else bad "$1" "$2 does not contain: $3"; fi
+}
+
+# Same as check, but a missing file is "not applicable yet" rather than drift.
+# The template ships without a deploy script; this starts checking once you add one.
+opt_check() { # opt_check LABEL FILE LITERAL
+  if [ ! -f "$2" ]; then note "$1 ($2 not present)"; return; fi
+  if has "$2" "$3"; then ok "$1"; else bad "$1" "$2 does not contain: $3"; fi
+}
+
+printf 'branding check (canonical: %s / "%s")\n\n' "$PKG" "$DISPLAY"
+
+printf 'build manifests\n'
+check "Cargo.toml package name"   Cargo.toml   "name = \"$PKG\""
+check "Cargo.toml homepage"       Cargo.toml   "homepage = \"$HOMEPAGE\""
+check "Cargo.toml description"    Cargo.toml   "description = \"$DESCRIPTION\""
+check "bundler.toml table key"    bundler.toml "[$PKG]"
+check "bundler.toml display name" bundler.toml "name = \"$DISPLAY\""
+
+printf '\nsource identity (src/lib.rs)\n'
+check "Plugin::NAME"    src/lib.rs "const NAME: &'static str = \"$PLUGIN_NAME\""
+check "Plugin::VENDOR"  src/lib.rs "const VENDOR: &'static str = \"$VENDOR\""
+check "Plugin::EMAIL"   src/lib.rs "const EMAIL: &'static str = \"$EMAIL\""
+check "CLAP_ID"         src/lib.rs "const CLAP_ID: &'static str = \"$CLAP_ID\""
+check "CLAP_DESCRIPTION" src/lib.rs "const CLAP_DESCRIPTION: Option<&'static str> = Some(\"$CLAP_DESCRIPTION\")"
+check "VST3_CLASS_ID"   src/lib.rs "const VST3_CLASS_ID: [u8; 16] = *b\"$VST3_CLASS_ID\""
+
+# Plugin::URL is env!("CARGO_PKG_HOMEPAGE"), so the manifest is the only place
+# it is spelled. Assert the indirection is still in place rather than hardcoded.
+check "Plugin::URL from manifest" src/lib.rs "const URL: &'static str = env!(\"CARGO_PKG_HOMEPAGE\")"
+
+# VST3 class IDs are a fixed 16-byte array. A shorter or longer literal is a
+# compile error, but it is far clearer to say so here than to read rustc on it.
+n=$(printf '%s' "$VST3_CLASS_ID" | wc -c | tr -d ' ')
+if [ "$n" -eq 16 ]; then ok "VST3_CLASS_ID is 16 bytes"
+else bad "VST3_CLASS_ID is 16 bytes" "got $n bytes: \"$VST3_CLASS_ID\""; fi
+
+# CLAP IDs are reverse-DNS by convention and are compared verbatim by hosts, so
+# a stray space or capital is a silent identity change between machines.
+case "$CLAP_ID" in
+  *\ *|*[A-Z]*) bad "CLAP_ID is reverse-DNS safe" "no spaces or capitals allowed: \"$CLAP_ID\"" ;;
+  *.*)          ok  "CLAP_ID is reverse-DNS safe" ;;
+  *)            bad "CLAP_ID is reverse-DNS safe" "expected dotted reverse-DNS, got: \"$CLAP_ID\"" ;;
+esac
+
+printf '\nstructural names (src/lib.rs)\n'
+# Every site the type names appear. A rename that misses one is a compile error
+# rather than silent drift, but naming the site is faster than reading rustc,
+# and the Vst3Plugin impl sits behind a cfg so a default build never reports it.
+check "struct $STRUCT"              src/lib.rs "struct $STRUCT {"
+check "impl Plugin"                 src/lib.rs "impl Plugin for $STRUCT {"
+check "impl ClapPlugin"             src/lib.rs "impl ClapPlugin for $STRUCT {"
+check "impl Vst3Plugin"             src/lib.rs "impl Vst3Plugin for $STRUCT {"
+check "nih_export_clap!"            src/lib.rs "nih_export_clap!($STRUCT);"
+check "nih_export_vst3!"            src/lib.rs "nih_export_vst3!($STRUCT);"
+check "struct $PARAMS_STRUCT"       src/lib.rs "struct $PARAMS_STRUCT {"
+check "impl Default for params"     src/lib.rs "impl Default for $PARAMS_STRUCT {"
+check "params field type"           src/lib.rs "params: Arc<$PARAMS_STRUCT>,"
+
+printf '\ndocs\n'
+opt_check "README bundle command" README.md "cargo xtask bundle $PKG"
+
+printf '\ndeploy script\n'
+opt_check "deploy.ps1 default package" deploy.ps1 "\$Package = \"$PKG\""
+opt_check "deploy.ps1 VST3 bundle"     deploy.ps1 "\$vst3Name = \"$DISPLAY.vst3\""
+opt_check "deploy.ps1 CLAP bundle"     deploy.ps1 "\$clapName = \"$DISPLAY.clap\""
+
+printf '\nstale spellings\n'
+# File list for the scan below. Prefer git, so build output and any vendored
+# tree stay out of it. Fall back to find when this is not a checkout - an
+# exported tarball, or a CI step that fetched without git metadata - because
+# `git ls-files` there returns nothing, and an empty list would report every
+# stale spelling as absent. A check that passes hardest when it can see least
+# is worse than no check.
+if git rev-parse --is-inside-work-tree >/dev/null 2>&1; then
+  file_list() { git ls-files; }
+  scan_source="git"
+else
+  file_list() { find . -path ./.git -prune -o -path ./target -prune -o -type f -print | sed 's|^\./||'; }
+  scan_source="find (not a git checkout)"
+fi
+info "scanning tracked files via $scan_source"
+# Every canonical spelling concatenated, for the substring test below.
+CANONICAL_BLOB="$PKG
+$DESCRIPTION
+$CLAP_DESCRIPTION
+$STRUCT
+$PARAMS_STRUCT
+$DISPLAY
+$PLUGIN_NAME
+$VENDOR
+$EMAIL
+$HOMEPAGE
+$CLAP_ID
+$VST3_CLASS_ID"
+# Fed by here-doc rather than a pipe on purpose: a piped `while` runs in a
+# subshell, and the pass/fail counters it increments would be discarded.
+while IFS= read -r s; do
+  [ -n "$s" ] || continue
+
+  # Still part of a canonical value? Then it is current branding, not a leftover.
+  # This is what lets the list ship pre-seeded: entries arm themselves as you
+  # rename. Substring, not equality, because placeholders nest - "your-domain"
+  # lives inside the canonical CLAP_ID, and "YOUR-USERNAME" inside the homepage.
+  # Over-skipping is the safe direction: a false FAIL on a name you still use
+  # would train you to ignore this section.
+  case "$CANONICAL_BLOB" in
+    *"$s"*) note "\"$s\" (still canonical)"; continue ;;
+  esac
+
+  # This script names every placeholder by definition, so it can never be a hit.
+  hits=$(file_list 2>/dev/null | while read -r f; do
+           [ "$f" = "check-branding.sh" ] || { [ -f "$f" ] && grep -lF "$s" "$f" 2>/dev/null; }
+         done)
+  if [ -z "$hits" ]; then ok "no occurrences of \"$s\""
+  else bad "no occurrences of \"$s\"" "still present in: $(echo "$hits" | tr '\n' ' ')"; fi
+done <<STALE_LIST
+$STALE
+STALE_LIST
+
+# Template scaffolding, not drift: TODOs are legitimate while you are still
+# building. Reported so a finished plugin does not quietly ship with them.
+# `grep -c` prints 0 AND exits 1 when there are no matches, so `|| echo 0`
+# would append a second zero and make the count unparseable. Swallow the
+# status instead, and default an empty result (missing file) to zero.
+todos=$(grep -c 'TODO' src/lib.rs 2>/dev/null || :)
+[ -n "$todos" ] || todos=0
+printf '\nscaffolding\n'
+if [ "$todos" -eq 0 ]; then ok "no TODO markers left in src/lib.rs"
+else info "$todos TODO marker(s) still in src/lib.rs (not a failure)"; fi
+
+printf '\n%d passed, %d failed' "$pass" "$fail"
+[ "$skip" -gt 0 ] && printf ', %d skipped' "$skip"
+printf '\n'
+[ "$fail" -eq 0 ] || exit 1

src/lib.rs

@@ -1,6 +1,7 @@
 // SPDX-License-Identifier: Apache-2.0
 
 use nih_plug::prelude::*;
+use nih_plug_egui::{create_egui_editor, egui, widgets, EguiState};
 use std::sync::Arc;
 
 // ──────────────────────────────────────────────
@@ -8,31 +9,36 @@ use std::sync::Arc;
 // See musiikki/codename-206/src/params.rs for a real example.
 // ──────────────────────────────────────────────
 
-struct PluginParams;
+#[derive(Params)]
+struct PluginParams {
+    /// Editor window size, persisted with the plugin state.
+    #[persist = "editor-state"]
+    editor_state: Arc<EguiState>,
 
-impl Params for PluginParams {
-    fn as_slice(&self) -> &[AtomicParam] {
-        &[]
+    /// Example parameter — replace with your own. The `id` is the stable key the host
+    /// stores automation against, so never change it once you've shipped.
+    #[id = "gain"]
+    gain: FloatParam,
 }
 
-    fn as_mut_slice(&mut self) -> &mut [AtomicParam] {
-        &mut []
+impl Default for PluginParams {
+    fn default() -> Self {
+        Self {
+            editor_state: EguiState::from_size(320, 160),
+            gain: FloatParam::new(
+                "Gain",
+                util::db_to_gain(0.0),
+                FloatRange::Skewed {
+                    min: util::db_to_gain(-30.0),
+                    max: util::db_to_gain(30.0),
+                    factor: FloatRange::gain_skew_factor(-30.0, 30.0),
+                },
+            )
+            .with_smoother(SmoothingStyle::Logarithmic(50.0))
+            .with_unit(" dB")
+            .with_value_to_string(formatters::v2s_f32_gain_to_db(2))
+            .with_string_to_value(formatters::s2v_f32_gain_to_db()),
         }
-
-    fn param_by_id(&self, _id: ParamId) -> Option<&AtomicParam> {
-        None
-    }
-
-    fn param_by_id_mut(&mut self, _id: ParamId) -> Option<&mut AtomicParam> {
-        None
-    }
-
-    fn param_by_name(&self, _name: &str) -> Option<&AtomicParam> {
-        None
-    }
-
-    fn param_by_name_mut(&mut self, _name: &str) -> Option<&mut AtomicParam> {
-        None
     }
 }
 
@@ -40,18 +46,11 @@ impl Params for PluginParams {
 // Plugin
 // ──────────────────────────────────────────────
 
+#[derive(Default)]
 struct MyPlugin {
     params: Arc<PluginParams>,
 }
 
-impl Default for MyPlugin {
-    fn default() -> Self {
-        Self {
-            params: Arc::new(PluginParams),
-        }
-    }
-}
-
 impl Plugin for MyPlugin {
     // TODO: Replace these placeholder values with your plugin's metadata.
     const NAME: &'static str = "Plugin Name";
@@ -61,20 +60,18 @@ impl Plugin for MyPlugin {
 
     const VERSION: &'static str = env!("CARGO_PKG_VERSION");
 
-    const AUDIO_IO_LAYOUTS: &'static [AudioIOLayout] = &[
-        AudioIOLayout {
+    const AUDIO_IO_LAYOUTS: &'static [AudioIOLayout] = &[AudioIOLayout {
         main_input_channels: NonZeroU32::new(2),
         main_output_channels: NonZeroU32::new(2),
         ..AudioIOLayout::const_default()
-        },
-    ];
+    }];
 
     const MIDI_INPUT: MidiConfig = MidiConfig::None;
     const MIDI_OUTPUT: MidiConfig = MidiConfig::None;
 
     const SAMPLE_ACCURATE_AUTOMATION: bool = true;
 
-    type SysSysexMessage = ();
+    type SysExMessage = ();
     type BackgroundTask = ();
 
     fn params(&self) -> Arc<dyn Params> {
@@ -82,9 +79,19 @@ impl Plugin for MyPlugin {
     }
 
     fn editor(&mut self, _async_executor: AsyncExecutor<Self>) -> Option<Box<dyn Editor>> {
-        // TODO: Implement your egui editor here.
-        // return Some(Box::new(MyEditor::new(self.params.clone())));
-        None
+        // TODO: Build your own egui layout here.
+        let params = self.params.clone();
+        create_egui_editor(
+            self.params.editor_state.clone(),
+            (),
+            |_, _| {},
+            move |egui_ctx, setter, _state| {
+                egui::CentralPanel::default().show(egui_ctx, |ui| {
+                    ui.label("Gain");
+                    ui.add(widgets::ParamSlider::for_param(&params.gain, setter));
+                });
+            },
+        )
     }
 
     fn initialize(
@@ -104,19 +111,21 @@ impl Plugin for MyPlugin {
         _aux: &mut AuxiliaryBuffers,
         _context: &mut impl ProcessContext<Self>,
     ) -> ProcessStatus {
-        // TODO: Implement your DSP here.
-        // This is a passthrough — replace with your audio processing.
+        // TODO: Implement your DSP here. This applies the example gain parameter; note that
+        // the smoother is advanced once per frame so automation doesn't zipper.
         for mut frame in buffer.iter_samples() {
-            for ch in 0..frame.len() {
-                *frame.get_mut(ch).unwrap() = *frame.get(ch).unwrap();
+            let gain = self.params.gain.smoothed.next();
+            for sample in frame.iter_mut() {
+                *sample *= gain;
             }
         }
+
         ProcessStatus::Normal
     }
 }
 
 impl ClapPlugin for MyPlugin {
-    // TODO: Replace with a unique CLAP ID, e.g. "com.your-domain.your-plugin-name"
+    // TODO: Replace with a unique CLAP ID in reverse-DNS form, e.g. "com.acme.fuzzbox"
     const CLAP_ID: &'static str = "com.your-domain.plugin-name";
     const CLAP_DESCRIPTION: Option<&'static str> = Some("Your plugin description");
     const CLAP_MANUAL_URL: Option<&'static str> = Some(Self::URL);
@@ -124,13 +133,14 @@ impl ClapPlugin for MyPlugin {
     const CLAP_FEATURES: &'static [ClapFeature] = &[ClapFeature::AudioEffect];
 }
 
+#[cfg(feature = "vst3")]
 impl Vst3Plugin for MyPlugin {
     // TODO: Replace with a unique 16-byte Class ID.
     // Must be exactly 16 bytes — padded with '!' if shorter.
     const VST3_CLASS_ID: [u8; 16] = *b"Unique16CharId!!";
-    const VST3_SUBCATEGORIES: &'static [Vst3SubCategory] =
-        &[Vst3SubCategory::Fx];
+    const VST3_SUBCATEGORIES: &'static [Vst3SubCategory] = &[Vst3SubCategory::Fx];
 }
 
 nih_export_clap!(MyPlugin);
+#[cfg(feature = "vst3")]
 nih_export_vst3!(MyPlugin);