Expert Juce Vst

Real-time safety (non-negotiable)

In processBlock and anything called from it:

• No locks that can block; no allocation (new, std::vector::push_back, string ops, etc.).
• No file I/O, network, or plugin format APIs that may block.
• Use pre-allocated buffers, atomics or lock-free structures, or copy parameter values at block boundaries from APVTS (getRawParameterValue, smoothed values, or cached atomic copies updated from the message thread).

On the message / GUI thread: UI updates, preset browser, file dialogs, heavy work.

CMake / targets

• Prefer juce_add_plugin with explicit FORMATS (e.g. VST3 AU Standalone), PLUGIN_MANUFACTURER_CODE, PLUGIN_CODE, COMPANY_NAME, PRODUCT_NAME.
• Link JUCE modules with target_link_libraries on the plugin target; use target_sources for Source/*.cpp you add.
• After adding files or targets, the user rebuilds the same CMake preset they already use for this project.

Plugin types (CMake flags)

• Instrument: IS_SYNTH TRUE, MIDI input as needed.
• Effect: IS_SYNTH FALSE; set bus layout in processor constructor / isBusesLayoutSupported.
• MIDI effect: IS_MIDI_EFFECT TRUE when applicable.

Common host / format notes

• VST3: stable parameter IDs and sensible naming; respect bus layouts and sidechain when implemented.
• AU: same processor code; validate channel layouts and Cocoa editor lifetime on macOS.
• Standalone: useful for debugging; not a substitute for in-DAW testing.

Debugging checklist

• Clicks/glitches: buffer size changes, denormals, uninitialized state, race between GUI and audio thread.
• Silence: bus disablement, wrong channel routing, MIDI not reaching processor.
• Crashes on close: editor/processor destruction order, timers not cancelled, listeners not detached.

When suggesting code

• Prefer JUCE types (AudioBuffer, MidiBuffer, dsp:: where it fits) and patterns already used in Source/.
• Keep new parameters in APVTS and expose them consistently in editor + state save/load.
• Mention if a change requires rescan in the DAW or reinstall of the built plugin bundle.