Looking for VST3 plugin sample/template in SDK with VSTGUI Support OFF

Hello. I am new to VST3 development.
I am trying to create a plugin with no VST GUI support. It would be controlled by the host through parameter automation sliders only.
In CMakeLists.txt I set :

option(SMTG_ADD_VSTGUI "Add VSTGUI Support" OFF)

Don’t know if it is the right thing to do.

Unfortunately, I started to code with the AGain sample as a basis, which uses a GUI and I have to guess what Interfaces to use and what required functions to override, and which i can comment out.
So i guess the main file with issues is plug_controller.h

Relevant section :

#pragma once

//#include "vstgui/plugin-bindings/vst3editor.h"
#include "public.sdk/source/vst/vsteditcontroller.h"

#include <vector>

namespace Steinberg {
namespace Vst {

        //template <typename T>

        class PlugController : public EditControllerEx1, public IMidiMapping
                //using UIMessageController = PlugMessageController<PlugController>;

                static FUnknown* createInstance (void* /*context*/)
                        return (IEditController*)new PlugController;

                //---from IPluginBase--------
                tresult PLUGIN_API initialize (FUnknown* context) SMTG_OVERRIDE;
                tresult PLUGIN_API terminate () SMTG_OVERRIDE;

                tresult PLUGIN_API setComponentState (IBStream* state) SMTG_OVERRIDE;
                        //---from EditController-----
                //IPlugView* PLUGIN_API createView (const char* name) SMTG_OVERRIDE;
                //tresult PLUGIN_API setState (IBStream* state) SMTG_OVERRIDE;
                //tresult PLUGIN_API getState (IBStream* state) SMTG_OVERRIDE;
                tresult PLUGIN_API setParamNormalized (ParamID tag, ParamValue value) SMTG_OVERRIDE;
                tresult PLUGIN_API getParamStringByValue (ParamID tag, ParamValue valueNormalized,
                                                        String128 string) SMTG_OVERRIDE;
                tresult PLUGIN_API getParamValueByString (ParamID tag, TChar* string,
                                                        ParamValue& valueNormalized) SMTG_OVERRIDE;

                //---from ComponentBase-----
                tresult receiveText (const char* text) SMTG_OVERRIDE;

                //---from IMidiMapping-----------------
                tresult PLUGIN_API getMidiControllerAssignment (int32 busIndex, int16 channel,
                                                                CtrlNumber midiControllerNumber,
                                                                ParamID& tag) SMTG_OVERRIDE;
                //---from VST3EditorDelegate-----------
                DELEGATE_REFCOUNT (EditController)
                tresult PLUGIN_API queryInterface (const char* iid, void** obj) SMTG_OVERRIDE;


Although everything compiles properly it fails at one unit test with a segmentation fault.

TestSuite : General Tests

[Scan Editor Classes]
Info:  ===Scan Editor Classes ====================================
Info:  This component does not export an edit controller class ID!!!

[Scan Buses]
Info:  ===Scan Buses ====================================
Info:  => Audio Buses: [1 In(s) => 1 Out(s)]
Info:       In [0]: "Stereo In" (Main-Default Active) 
Info:       Out[0]: "Stereo Out" (Main-Default Active) 
Info:  => Event Buses: [1 In(s) => 0 Out(s)]
Info:       In [0]: "Event In" (Main-Default Active) 

[Scan Parameters]
Info:  ===Scan Parameters ====================================
Info:  No Edit Controller supplied!

[MIDI Mapping]
Info:  ===MIDI Mapping ====================================
Info:  No Edit Controller supplied!

[MIDI Learn]
Info:  ===MIDI Learn ====================================
Info:  No Edit Controller supplied!

[Scan Units]
Info:  ===Scan Units ====================================
Info:  This component has no units.

[Scan Programs]
Info:  ===Scan Programs ====================================
Info:  This component does not export any programs.
Segmentation fault

The best approach at this point seems to find a sample that does not make use of the VST GUI,
could you tell me which one I could use as a template ?
mda plugin sources seem quite straightforward and known to use no GUI, but I am not sure they are VST3.

Any information appreciated.

Additional environment info :
building on Debian buster (10)
libc+±15-dev:amd64 1:15.0.6-4b1+

CMakeLists.txt :

cmake_minimum_required(VERSION 3.15.0)
    VERSION 0.9.0
    DESCRIPTION "test compressor"

add_definitions(-D_DEBUG -DDEVELOPMENT)
set(vst3sdk_SOURCE_DIR /home/rod/git/VST_SDK/vst3sdk)

add_subdirectory(${vst3sdk_SOURCE_DIR} ${PROJECT_BINARY_DIR}/vst3sdk)

# Add and use VSTGUI (enable VST 3 Plug-ins Samples using VSTGUI)
option(SMTG_ADD_VSTGUI "Add VSTGUI Support" OFF)





please disregard and close.
There are mda vst3 plugins in the SDK.