lgarraza · Nov 4, 2026 · Nov 4, 2026 · Nov 4, 2026 · Nov 4, 2026 · Nov 4, 2026
diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
@@ -11,11 +11,12 @@ jobs:
       fail-fast: false
       matrix:
         os: [windows-latest, macos-latest]
+        edition: [full, lite]
     runs-on: ${{ matrix.os }}
     steps:
       - uses: actions/checkout@v4
       - name: Configure
-        run: cmake -S . -B build -DCMAKE_BUILD_TYPE=Release "-DCMAKE_OSX_ARCHITECTURES=arm64;x86_64"
+        run: cmake -S . -B build -DCMAKE_BUILD_TYPE=Release "-DCMAKE_OSX_ARCHITECTURES=arm64;x86_64" "-DKSP_ENABLE_VST_HOST=${{ matrix.edition == 'full' && 'ON' || 'OFF' }}"
       - name: Build
         run: cmake --build build --config Release --parallel
       - name: Tests

diff --git a/App/AppFolders.h b/App/AppFolders.h
@@ -0,0 +1,18 @@
+/*
+    AppFolders.h
+    Where the app keeps its own files: Documents/KeyStepPro Studio (the library, backups and the like).
+*/
+
+#pragma once
+
+#include <juce_core/juce_core.h>
+
+namespace ksp
+{
+
+inline juce::File dataFolder()
+{
+    return juce::File::getSpecialLocation (juce::File::userDocumentsDirectory).getChildFile ("KeyStepPro Studio");
+}
+
+} // namespace ksp
diff --git a/App/LibraryWindow.h b/App/LibraryWindow.h
@@ -33,7 +33,9 @@ class LibraryPanel : public juce::Component, private juce::TableListBoxModel
         h.addColumn ("Name", 1, 240, 100, 600);
         h.addColumn ("Changed", 2, 140, 80, 220);
         h.addColumn ("KeyStep project", 3, 270, 100, 500);
+#if KSP_ENABLE_VST_HOST
         h.addColumn ("Instruments", 4, 200, 80, 500);
+#endif
         h.setStretchToFitActive (true);
 
         openButton.setButtonText ("Open");
@@ -140,17 +142,20 @@ class LibraryPanel : public juce::Component, private juce::TableListBoxModel
             text = juce::String (e.modified).replaceCharacter ('T', ' ').upToFirstOccurrenceOf ("Z", false, false);
         else if (column == 3)
             text = e.summary;
+#if KSP_ENABLE_VST_HOST
         else
         {
             for (const auto& n : e.instruments)
                 text += (text.isEmpty() ? "" : ", ") + juce::String (n);
         }
+#endif
         g.setColour (ksp::ui::palette::ink);
         g.setFont (14.0f);
         g.drawText (text, 4, 0, w - 8, h, juce::Justification::centredLeft, true);
     }
 
     void selectedRowsChanged (int) override { updateButtons(); }
+    void returnKeyPressed (int) override { openSelected(); }
     void cellDoubleClicked (int row, int, const juce::MouseEvent&) override
     {
         table.selectRow (row);

diff --git a/App/Main.cpp b/App/Main.cpp
diff --git a/CLAUDE.md b/CLAUDE.md
@@ -22,6 +22,9 @@ App JUCE 8 (Standalone, Windows y Mac) para el Arturia KeyStep Pro: editor de pr
 - No mencionar otros proyectos de Leo en el código ni en los docs (Leo, 2026-10-30): el repo es público y trata solo del KSP.
 - Testear lo justo (app personal): `protocol_test` y los tests sin JUCE de lo que se toca.
 
+## Ediciones (Leo, 2026-11-04)
+- Un solo repo, dos builds, las dos mantenidas: Lite (solo editor) es la edición PRINCIPAL y recomendada (Leo: el host de VST aleja la app de su propósito, editar proyectos visualmente); Full agrega VST3, audio y WAV. Opción CMake `KSP_ENABLE_VST_HOST` (OFF por defecto = Lite) y macro `KSP_ENABLE_VST_HOST` en App/Main.cpp, App/LibraryWindow.h. Lite no enlaza juce_audio_processors / audio_utils ni compila Source/Host. Todo lo que sea del editor, la sincronización y el MIDI va en las dos; el código de VST solo dentro de `#if KSP_ENABLE_VST_HOST`. Source/Mix/Transport.h (reloj del KSP) y App/AppFolders.h son comunes. Instaladores: `build-installer.ps1` (Lite, sin sufijo: KeyStepProStudio-Setup-x.y.z.exe) y `-Full` (KeyStepProStudio-Full-Setup-x.y.z.exe). CI compila las dos ediciones en Windows y Mac.
+
 ## Build
 - `cmake -S . -B build -DCMAKE_BUILD_TYPE=Release` y `cmake --build build --config Release`. JUCE 8.0.4 se descarga solo (FetchContent) o se usa uno local con `-DJUCE_DIR=...`.
 - Windows: Visual Studio 2022/2026 con CMake (o `cmake -G "Visual Studio 17 2022"`). Mac: Xcode o Ninja.
@@ -39,7 +42,6 @@ App JUCE 8 (Standalone, Windows y Mac) para el Arturia KeyStep Pro: editor de pr
 - Tools/KspRestore/Main.cpp: fase 1b, `--file X --project N [--to M] [--write]`: backup previo del slot (ksp-pre-restore-P<M>-*.json), sin `--write` es un dry run; con `--write` abre sesión, manda, commit (3 s) y relee. Solo manda tramas al slot M (`ksp::isWriteFor`).
 - App/KspStyle.h: look del KeyStep Pro (paleta chasis blanco / panel negro / colores de track verde-naranja-amarillo-rojo, botones grises con bisel, brillo en lo encendido, KspLookAndFeel, TrackTabs, SevenSegDisplay de 7 segmentos). Los colores van en ksp::ui::palette; no hardcodear colores en las ventanas.
 - App/Main.cpp: KeyStepProStudio (fase 2): editor de patterns, abre un backup o lee del equipo, escribe a los 16 slots con backup previo y relectura. Source/Ksp/Device.h (JUCE): open, readSlot, backupSlot, writeSlot; lo usan la app y KspRestore.
-- Source/Model/Overdub.h: grabación en tiempo real (overdub) sobre un Pattern desde MIDI crudo: clock desde Start, paso más cercano módulo el largo, solo suma notas y salta las que ya están en el paso (el KSP tocando lo guardado). Lo usa el botón Rec de la app con Device::setListener.
 - Source/Model/Pattern.h: un pattern de secuenciador (largo, root, escala, pasos con notas) leído de y escrito en un ProjectData, sin tocar el equipo; después `writePlan` lo manda. Portado de edReadPattern / edWritePattern de KSCON. No toca drums ni arpegiador.
 - Source/Model/NoteMove.h: mover / copiar un grupo de notas de un Pattern (arrastre del grid), todo o nada, y sameSteps para el Undo del grid; tests/notemove_test.cpp.
 - Source/Model/PatternOps.h: nudge / reverse / invert de un Pattern entero (botón Ops de la app); tests/patternops_test.cpp.
@@ -57,7 +59,7 @@ App JUCE 8 (Standalone, Windows y Mac) para el Arturia KeyStep Pro: editor de pr
 - App/GeneratorWindow.h: la ventana Generate... (estilo, mood, semilla, cadenas, velocidad) que escribe patterns y scenes en el proyecto abierto, con deshacer.
 - Source/Gen/Theory.h (Chord, Params, escalas, RNG) + Roles.h (motor de roles: RoleSpec = drone/pad/melody/bells/bass/stab con densidad, registro, largo, pulsos y gate; euclid; makeDrumPattern con DrumSpec) + Ambient.h (el preset ambient = 4 RoleSpec, misma salida que antes: hash congelado en tests/gen_test.cpp) + Styles.h (presets techno/house/dnb: drums en el track 1 en drum mode, bajo, acordes, lead; `applyStyle`) + Arrangement.h (arreglo musical: 8 scenes con curva de energía; patterns 1-5 drums, 1-12 y 16 vacío en T2-T4; `applyArrangement`). En drum mode el instrumento del track 1 escucha el canal 10.
 - Source/Gen/Ambient.h: generador ambient (4 tracks, largos 16/13/17/19, semilla, scenes, cadenas, moods ethereal/dark/meditative). Tools/KspGen/Main.cpp: lo escribe a un slot 10-16 con backup y relectura. tests/gen_test.cpp.
-- tests/protocol_test.cpp: tramas contra las capturas de KSCON en hardware. tests/backup_test.cpp: plan, lectura con un equipo falso y JSON. tests/restore_test.cpp: JSON ida y vuelta, orden de envío, arreglo de drums, relectura. tests/pattern_test.cpp: leer / editar / escribir un pattern, límites. tests/overdub_test.cpp: cuantizado al paso, dedupe, canal, Start/Stop/Continue, límites.
+- tests/protocol_test.cpp: tramas contra las capturas de KSCON en hardware. tests/backup_test.cpp: plan, lectura con un equipo falso y JSON. tests/restore_test.cpp: JSON ida y vuelta, orden de envío, arreglo de drums, relectura. tests/pattern_test.cpp: leer / editar / escribir un pattern, límites.
 
 ## Manual
 - docs/manual/ (inglés): README con el estado por fase, protocolo y reglas de seguridad, herramientas, modelo, app y bitácora de hardware. Cada PR que cambie comportamiento, herramientas o resultados lo actualiza; es el contexto para tareas futuras. Conciso.

diff --git a/CMakeLists.txt b/CMakeLists.txt
@@ -42,9 +42,6 @@ add_test(NAME mix_test COMMAND mix_test)
 add_executable(gen_test tests/gen_test.cpp)
 target_link_libraries(gen_test PRIVATE ksp_core)
 add_test(NAME gen_test COMMAND gen_test)
-add_executable(overdub_test tests/overdub_test.cpp)
-target_link_libraries(overdub_test PRIVATE ksp_core)
-add_test(NAME overdub_test COMMAND overdub_test)
 add_executable(notemove_test tests/notemove_test.cpp)
 target_link_libraries(notemove_test PRIVATE ksp_core)
 add_test(NAME notemove_test COMMAND notemove_test)
@@ -62,6 +59,9 @@ target_link_libraries(KspCompare PRIVATE ksp_core)
 # JUCE: a local checkout with -DJUCE_DIR=..., otherwise downloaded once into the build folder.
 # KSP_TESTS_ONLY=ON skips JUCE entirely (fast checks of the no-JUCE code).
 option(KSP_TESTS_ONLY "Build only the tests without JUCE" OFF)
+# Lite (OFF, the default and the recommended edition) is the editor alone, without the VST3 SDK.
+# Full (ON) adds VST3 instruments and effects, audio output and WAV recording.
+option(KSP_ENABLE_VST_HOST "Build the Full edition with VST3 hosting (OFF = Lite, the default)" OFF)
 if(NOT KSP_TESTS_ONLY)
     set(JUCE_DIR "" CACHE PATH "Local JUCE checkout (empty = download)")
     if(JUCE_DIR)
@@ -115,42 +115,46 @@ if(NOT KSP_TESTS_ONLY)
         juce::juce_recommended_config_flags
         juce::juce_recommended_warning_flags)
 
-    # Phase 3: out-of-process VST3 scanner (one plugin file per run; a crash kills only this process).
-    juce_add_console_app(KspVstHelper PRODUCT_NAME "KspVstHelper")
-    target_sources(KspVstHelper PRIVATE Tools/KspVstHelper/Main.cpp)
-    target_compile_definitions(KspVstHelper PRIVATE JUCE_WEB_BROWSER=0 JUCE_USE_CURL=0 JUCE_PLUGINHOST_VST3=1 JUCE_PLUGINHOST_AU=0)
-    target_link_libraries(KspVstHelper PRIVATE
-        juce::juce_audio_processors
-        juce::juce_recommended_config_flags
-        juce::juce_recommended_warning_flags)
+    if(KSP_ENABLE_VST_HOST)
+        # Phase 3: out-of-process VST3 scanner (one plugin file per run; a crash kills only this process).
+        juce_add_console_app(KspVstHelper PRODUCT_NAME "KspVstHelper")
+        target_sources(KspVstHelper PRIVATE Tools/KspVstHelper/Main.cpp)
+        target_compile_definitions(KspVstHelper PRIVATE JUCE_WEB_BROWSER=0 JUCE_USE_CURL=0 JUCE_PLUGINHOST_VST3=1 JUCE_PLUGINHOST_AU=0)
+        target_link_libraries(KspVstHelper PRIVATE
+            juce::juce_audio_processors
+            juce::juce_recommended_config_flags
+            juce::juce_recommended_warning_flags)
 
-    # Phase 3: checks that a scanned VST3 instrument loads, sounds and restores its state (no audio device, no window).
-    juce_add_console_app(KspHostCheck PRODUCT_NAME "KspHostCheck")
-    target_sources(KspHostCheck PRIVATE Tools/KspHostCheck/Main.cpp)
-    target_compile_definitions(KspHostCheck PRIVATE JUCE_WEB_BROWSER=0 JUCE_USE_CURL=0 JUCE_PLUGINHOST_VST3=1 JUCE_PLUGINHOST_AU=0)
-    target_link_libraries(KspHostCheck PRIVATE
-        ksp_core
-        juce::juce_audio_processors
-        juce::juce_audio_formats
-        juce::juce_recommended_config_flags
-        juce::juce_recommended_warning_flags)
+        # Phase 3: checks that a scanned VST3 instrument loads, sounds and restores its state (no audio device, no window).
+        juce_add_console_app(KspHostCheck PRODUCT_NAME "KspHostCheck")
+        target_sources(KspHostCheck PRIVATE Tools/KspHostCheck/Main.cpp)
+        target_compile_definitions(KspHostCheck PRIVATE JUCE_WEB_BROWSER=0 JUCE_USE_CURL=0 JUCE_PLUGINHOST_VST3=1 JUCE_PLUGINHOST_AU=0)
+        target_link_libraries(KspHostCheck PRIVATE
+            ksp_core
+            juce::juce_audio_processors
+            juce::juce_audio_formats
+            juce::juce_recommended_config_flags
+            juce::juce_recommended_warning_flags)
+    endif()
 
     # Phase 2: KeyStepPro Studio, the editor app.
     # Icon: App/Resources/*.png from Tools/make_icon.py (the four track colours); JUCE makes the .ico / .icns.
     juce_add_gui_app(KeyStepProStudio PRODUCT_NAME "KeyStepPro Studio" COMPANY_NAME "KeyStepPro Studio"
         BUNDLE_ID io.github.lgarraza.keystepprostudio
         ICON_BIG App/Resources/icon.png ICON_SMALL App/Resources/icon_small.png)
     target_sources(KeyStepProStudio PRIVATE App/Main.cpp)
-    target_compile_definitions(KeyStepProStudio PRIVATE JUCE_WEB_BROWSER=0 JUCE_USE_CURL=0 JUCE_PLUGINHOST_VST3=1 JUCE_PLUGINHOST_AU=0 JUCE_APPLICATION_NAME_STRING="KeyStepPro Studio" JUCE_APPLICATION_VERSION_STRING="${PROJECT_VERSION}")
+    target_compile_definitions(KeyStepProStudio PRIVATE JUCE_WEB_BROWSER=0 JUCE_USE_CURL=0 KSP_ENABLE_VST_HOST=$<BOOL:${KSP_ENABLE_VST_HOST}> JUCE_APPLICATION_NAME_STRING="KeyStepPro Studio" JUCE_APPLICATION_VERSION_STRING="${PROJECT_VERSION}")
     target_link_libraries(KeyStepProStudio PRIVATE
         ksp_core
         juce::juce_gui_basics
         juce::juce_audio_devices
-        juce::juce_audio_processors
-        juce::juce_audio_utils
         juce::juce_recommended_config_flags
         juce::juce_recommended_warning_flags)
-    add_dependencies(KeyStepProStudio KspVstHelper)
-    add_custom_command(TARGET KeyStepProStudio POST_BUILD
-        COMMAND ${CMAKE_COMMAND} -E copy_if_different $<TARGET_FILE:KspVstHelper> $<TARGET_FILE_DIR:KeyStepProStudio>)
+    if(KSP_ENABLE_VST_HOST)
+        target_compile_definitions(KeyStepProStudio PRIVATE JUCE_PLUGINHOST_VST3=1 JUCE_PLUGINHOST_AU=0)
+        target_link_libraries(KeyStepProStudio PRIVATE juce::juce_audio_processors juce::juce_audio_utils)
+        add_dependencies(KeyStepProStudio KspVstHelper)
+        add_custom_command(TARGET KeyStepProStudio POST_BUILD
+            COMMAND ${CMAKE_COMMAND} -E copy_if_different $<TARGET_FILE:KspVstHelper> $<TARGET_FILE_DIR:KeyStepProStudio>)
+    endif()
 endif()
diff --git a/README.md b/README.md
@@ -1,24 +1,40 @@
 # KeyStepPro Studio
 
 A free desktop companion for the **Arturia KeyStep Pro**: edit its sequencer patterns on a big screen, keep a library of
-projects on your computer, and play the KeyStep through your own VST3 instruments without opening a DAW.
+projects on your computer, and generate new music for it. An optional Full edition also plays the KeyStep through your own
+VST3 instruments.
 
 ![KeyStepPro Studio main window](docs/images/main-window.png)
 
 Windows (tested) and macOS (builds from the same code, not tested lately). Not affiliated with Arturia.
 
+## Editions
+
+**We recommend Lite.** The app was made to edit KeyStep Pro projects visually, and Lite does exactly that. Full adds
+VST3 hosting, which takes the app a bit away from that purpose. Both editions are maintained from one source tree
+(CMake option `KSP_ENABLE_VST_HOST`, OFF by default = Lite):
+
+| | **Lite** (recommended) | Full |
+| --- | --- | --- |
+| Pattern editor, library, Project Map, generator, backups, sync, MIDI monitor | yes | yes |
+| KeyStep clock readout (PLAY / STOP, position, BPM) | yes | yes |
+| VST3 instruments, effects, audio output, WAV recording | no | yes |
+
+Lite has no VST3 SDK and no audio engine, so it is smaller and builds faster. Each release has both installers
+(`KeyStepProStudio-Setup-x.y.z.exe` for Lite and `KeyStepProStudio-Full-Setup-x.y.z.exe`); installing one replaces the other.
+Build Full with `cmake -S . -B build-full -DKSP_ENABLE_VST_HOST=ON`.
+
 ## What it does
 
 - **Pattern editor.** Read a project from the KeyStep over USB (or open a backup), see all 64 steps of every pattern,
   add, delete and edit notes (pitch, gate, velocity, time shift, randomness), change length, root and scale, copy patterns,
   shift a track by an octave, and write the result back to the KeyStep.
-- **Overdub.** Press Rec, hit Play on the KeyStep and play over the loop; notes land on the nearest step.
 - **Library.** Your projects live on the computer (`Documents/KeyStepPro Studio/Library`), with names, notes and the
   instruments of each track. The KeyStep's 16 slots are treated as a working area: open and edit projects without the
   KeyStep connected, load one into a slot when you want to play it.
-- **VST3 host.** One VST3 instrument per KeyStep track (T1 to T4 on MIDI channels 1 to 4), up to four effect inserts per
+- **VST3 host (Full edition).** One VST3 instrument per KeyStep track (T1 to T4 on MIDI channels 1 to 4), up to four effect inserts per
   track and a master effect chain with a limiter. The KeyStep is the clock: its Play and Stop drive the app.
-- **WAV recording** of the mix and/or one stem per track, started and stopped by the KeyStep's transport.
+- **WAV recording (Full edition)** of the mix and/or one stem per track, started and stopped by the KeyStep's transport.
 - **Generator** (Generate...): writes patterns and scenes into the open project in a style (Ambient with four moods,
   Techno, House deep / chill / melodic, Drum & bass) with a seed, pattern chains and undo. The styles add drums on track 1
   and set the project tempo.
@@ -52,7 +68,7 @@ start writing to your KeyStep.
 
 ## Install (Windows)
 
-1. Download `KeyStepProStudio-Setup-x.y.z.exe` from [Releases](../../releases) and run it. It installs the app, the
+1. Download `KeyStepProStudio-Setup-x.y.z.exe` (Lite, recommended; `KeyStepProStudio-Full-Setup-x.y.z.exe` adds VST3 hosting) from [Releases](../../releases) and run it. It installs the app, the
    VST3 helper and the command-line tools, and adds a Start menu entry. Prefer no installer? Download
    `KeyStepProStudio-x.y.z-portable.zip` instead, unzip it anywhere and run `KeyStepPro Studio.exe`.
 2. The installer and the app are **not code-signed** (see [docs/signing.md](docs/signing.md)). Windows SmartScreen will
@@ -69,7 +85,7 @@ start writing to your KeyStep.
    selected note. Switch track and pattern at the top.
 3. **Save** keeps the project in your library. **Write to slot** sends it to a slot from 10 to 16 (backed up and
    verified as described above).
-4. To play it through VST3 instruments: **Scan plugins** once, pick an instrument per track in the rows under the grid,
+4. Full edition only: to play it through VST3 instruments: **Scan plugins** once, pick an instrument per track in the rows under the grid,
    choose your audio device with **Audio...**, and press Play on the KeyStep.
 
 **New to the app?** Start with the [User guide](docs/manual/user/README.md). Developer notes: [docs/manual](docs/manual/README.md).
@@ -84,7 +100,7 @@ Installed next to the app; useful for backups and troubleshooting.
 | `KspBackup` | no | Backup of all projects and the global settings to JSON (about 10 minutes). |
 | `KspRestore` | only with `--write` | Restore a project from a backup to a slot (backup first, read back after). |
 | `KspGen` | only with `--write` | Generate an ambient project, or a style with `--style`, into a slot. |
-| `KspHostCheck` | no | Check that a VST3 instrument or effect loads, sounds and restores its state. |
+| `KspHostCheck` (Full only) | no | Check that a VST3 instrument or effect loads, sounds and restores its state. |
 
 Details in [docs/manual/02-tools.md](docs/manual/02-tools.md).
 

diff --git a/Source/Mix/Transport.h b/Source/Mix/Transport.h
@@ -56,6 +56,8 @@ class Transport
     long ticks() const noexcept { return tickCount.load(); }
     /** The tempo in BPM from the clock (120 until a clock arrives). */
     double bpm() const noexcept { return tempo.load(); }
+    /** Has a tempo been measured from the clock yet? */
+    bool hasTempo() const noexcept { return measured.load(); }
     /** How many Start / Continue and Stop messages arrived: a watcher compares them with what it saw last. */
     std::uint32_t starts() const noexcept { return startCounter.load(); }
     std::uint32_t stops() const noexcept { return stopCounter.load(); }
@@ -84,6 +86,7 @@ class Transport
             {
                 average = average == 0.0 ? dt : 0.95 * average + 0.05 * dt;
                 tempo.store (60.0 / (kClocksPerQuarter * average));
+                measured.store (true);
             }
         }
         lastClock = now;
@@ -92,6 +95,7 @@ class Transport
     std::atomic<bool> playingNow { false };
     std::atomic<long> tickCount { 0 };
     std::atomic<double> tempo { 120.0 };
+    std::atomic<bool> measured { false };
     std::atomic<std::uint32_t> startCounter { 0 }, stopCounter { 0 };
     double lastClock = 0.0, average = 0.0;   // MIDI thread only
 };