diff --git a/Makefile b/Makefile
index 17c6f4f..1152361 100644
--- a/Makefile
+++ b/Makefile
@@ -35,7 +35,11 @@ endif
 
 endif
 
+# --------------------------------------------------------------
+# Check for X11+OpenGL dependencies (unless headless build)
+
 ifneq ($(HAIKU_OR_MACOS_OR_WINDOWS),true)
+ifneq ($(HEADLESS),true)
 
 ifneq ($(HAVE_OPENGL),true)
 $(error X11 dependency not installed/available)
@@ -50,6 +54,7 @@ ifneq ($(HAVE_XRANDR),true)
 $(warning Xrandr dependency not installed/available)
 endif
 
+endif
 endif
 
 # --------------------------------------------------------------
@@ -63,7 +68,9 @@ ifneq ($(SYSDEPS),true)
 endif
 
 dgl:
+ifneq ($(HEADLESS),true)
 	$(MAKE) -C dpf/dgl opengl USE_NANOVG_FBO=true
+endif
 
 plugins: deps
 	$(MAKE) all -C plugins
diff --git a/deps/Makefile b/deps/Makefile
index 8cbe099..5b42a3a 100644
--- a/deps/Makefile
+++ b/deps/Makefile
@@ -136,15 +136,24 @@ $(DEP_PATH)/libarchive-3.4.3/.stamp-patched:
 	sed -i -e "s/TARGETS archive archive_static/TARGETS archive_static/" $(DEP_PATH)/libarchive-3.4.3/libarchive/CMakeLists.txt
 	touch $@
 
-ifeq ($(MACOS),true)
+# skip libsamplerate tests
+$(DEP_PATH)/lib/libsamplerate.a: $(DEP_PATH)/libsamplerate-0.1.9/.stamp-patched
+
+$(DEP_PATH)/libsamplerate-0.1.9/.stamp-patched:
+	$(DEP_MAKE) -C $(DEP_PATH) libsamplerate-0.1.9
+	sed -i -e "s/src doc examples tests/src/" $(DEP_PATH)/libsamplerate-0.1.9/Makefile.in
+	touch $@
+
 # zstd cmake is borked, see https://github.com/facebook/zstd/issues/1401
+# zstd also fails to build on old systems, patch that too
 $(DEP_PATH)/lib/libzstd.a: $(DEP_PATH)/zstd-1.4.5/.stamp-patched
 
 $(DEP_PATH)/zstd-1.4.5/.stamp-patched:
 	$(DEP_MAKE) -C $(DEP_PATH) zstd-1.4.5
 	sed -i -e "56,66d" $(DEP_PATH)/zstd-1.4.5/build/cmake/CMakeModules/AddZstdCompilationFlags.cmake
+	sed -i -e "146,175d" $(DEP_PATH)/zstd-1.4.5/programs/util.c
+	sed -i -e "142,144d" $(DEP_PATH)/zstd-1.4.5/programs/util.c
 	touch $@
-endif
 
 # --------------------------------------------------------------
 # Build targets
diff --git a/include/GL/gl.h b/include/GL/gl.h
new file mode 100644
index 0000000..4450158
--- /dev/null
+++ b/include/GL/gl.h
@@ -0,0 +1,41 @@
+/*
+ * DISTRHO Cardinal Plugin
+ * Copyright (C) 2021 Filipe Coelho <falktx@falktx.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 3 of
+ * the License, or any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * For a full copy of the GNU General Public License see the LICENSE file.
+ */
+
+// this file matches the top of `OpenGL.hpp` provided by DPF
+
+#pragma once
+
+#ifdef HEADLESS
+# define GL_COLOR_BUFFER_BIT 0
+# define GL_DEPTH_BUFFER_BIT 0
+# define GL_STENCIL_BUFFER_BIT 0
+# define GL_PROJECTION 0
+# define GL_TRIANGLES 0
+static inline void glBegin(int) {}
+static inline void glEnd() {}
+static inline void glColor3f(float, float, float) {}
+static inline void glVertex3f(float, float, float) {}
+static inline void glClear(int) {}
+static inline void glClearColor(double, double, double, double) {}
+static inline void glLoadIdentity() {}
+static inline void glMatrixMode(int) {}
+static inline void glOrtho(double, double, double, double, double, double) {}
+static inline void glViewport(double, double, double, double) {}
+typedef unsigned int GLuint;
+#else
+# include_next <GL/gl.h>
+#endif
diff --git a/include/GL/glew.h b/include/GL/glew.h
index 2ec0dd6..3332e71 100644
--- a/include/GL/glew.h
+++ b/include/GL/glew.h
@@ -78,20 +78,22 @@
 // -----------------------------------------------------------------------
 // OpenGL includes
 
-#ifdef DISTRHO_OS_MAC
-# ifdef DGL_USE_OPENGL3
-#  include <OpenGL/gl3.h>
-#  include <OpenGL/gl3ext.h>
+#ifndef HEADLESS
+# ifdef DISTRHO_OS_MAC
+#  ifdef DGL_USE_OPENGL3
+#   include <OpenGL/gl3.h>
+#   include <OpenGL/gl3ext.h>
+#  else
+#   include <OpenGL/gl.h>
+#  endif
 # else
-#  include <OpenGL/gl.h>
-# endif
-#else
-# ifdef DISTRHO_OS_WINDOWS
-#  define GL_GLEXT_PROTOTYPES
-# endif
-# ifndef __GLEW_H__
-#  include <GL/gl.h>
-#  include <GL/glext.h>
+#  ifdef DISTRHO_OS_WINDOWS
+#   define GL_GLEXT_PROTOTYPES
+#  endif
+#  ifndef __GLEW_H__
+#   include <GL/gl.h>
+#   include <GL/glext.h>
+#  endif
 # endif
 #endif
 
diff --git a/include/neon-compat/pmmintrin.h b/include/neon-compat/pmmintrin.h
index 7d1091c..b21efb9 100644
--- a/include/neon-compat/pmmintrin.h
+++ b/include/neon-compat/pmmintrin.h
@@ -25,7 +25,7 @@
 static inline
 void __builtin_ia32_pause()
 {
-    __asm__ __volatile__("isb\n");
+    // __asm__ __volatile__("isb\n");
 }
 
 static inline
diff --git a/plugins/Makefile b/plugins/Makefile
index e5e7c25..ae07729 100644
--- a/plugins/Makefile
+++ b/plugins/Makefile
@@ -286,6 +286,10 @@ BASE_FLAGS += -I../include/mingw-compat
 BASE_FLAGS += -I../include/mingw-std-threads
 endif
 
+ifeq ($(HEADLESS),true)
+BASE_FLAGS += -DHEADLESS
+endif
+
 ifeq ($(WITH_LTO),true)
 BASE_FLAGS += -fno-strict-aliasing -flto
 endif
diff --git a/src/CardinalPlugin.cpp b/src/CardinalPlugin.cpp
index 664efa9..0ae3550 100644
--- a/src/CardinalPlugin.cpp
+++ b/src/CardinalPlugin.cpp
@@ -46,7 +46,7 @@ namespace plugin {
     void initStaticPlugins();
     void destroyStaticPlugins();
 }
-#ifdef __MOD_DEVICES__
+#if defined(__MOD_DEVICES__) && !defined(HEADLESS)
 namespace window {
     void WindowInit(Window* window, DISTRHO_NAMESPACE::Plugin* plugin);
 }
@@ -70,6 +70,9 @@ struct Initializer {
         settings::isPlugin = true;
         settings::skipLoadOnLaunch = true;
         settings::showTipsOnLaunch = false;
+#ifdef HEADLESS
+        settings::headless = true;
+#endif
 #ifdef __MOD_DEVICES__
         settings::threadCount = 3;
 #else
@@ -244,7 +247,7 @@ public:
         context->patch->loadTemplate();
         context->engine->startFallbackThread();
 
-#ifdef __MOD_DEVICES__
+#if defined(__MOD_DEVICES__) && !defined(HEADLESS)
         context->window = new rack::window::Window;
         rack::window::WindowInit(context->window, this);
         /*
@@ -260,17 +263,10 @@ public:
         {
             const MutexLocker cml(context->mutex);
             rack::contextSet(context);
-#ifdef __MOD_DEVICES__
+#if defined(__MOD_DEVICES__) && !defined(HEADLESS)
             delete context->window;
             context->window = nullptr;
 #endif
-
-            /*
-            delete context->scene;
-            context->scene = nullptr;
-            delete context->event;
-            context->event = nullptr;
-            */
         }
 
         delete context;
diff --git a/src/DistrhoPluginInfo.h b/src/DistrhoPluginInfo.h
index d1ed90f..cb8a88e 100644
--- a/src/DistrhoPluginInfo.h
+++ b/src/DistrhoPluginInfo.h
@@ -22,7 +22,14 @@
 #define DISTRHO_PLUGIN_NAME  "Cardinal"
 #define DISTRHO_PLUGIN_URI   "https://distrho.kx.studio/plugins/cardinal"
 
+#ifdef HEADLESS
+#define DISTRHO_PLUGIN_HAS_UI             0
+#else
 #define DISTRHO_PLUGIN_HAS_UI             1
+#define DISTRHO_PLUGIN_WANT_DIRECT_ACCESS 1
+#define DISTRHO_UI_USE_NANOVG             1
+#define DISTRHO_UI_USER_RESIZABLE         1
+#endif
 #define DISTRHO_PLUGIN_NUM_INPUTS         2
 #define DISTRHO_PLUGIN_NUM_OUTPUTS        2
 #define DISTRHO_PLUGIN_WANT_MIDI_INPUT    1
@@ -30,11 +37,8 @@
 #define DISTRHO_PLUGIN_WANT_FULL_STATE    1
 #define DISTRHO_PLUGIN_WANT_STATE         1
 #define DISTRHO_PLUGIN_WANT_TIMEPOS       1
-#define DISTRHO_PLUGIN_WANT_DIRECT_ACCESS 1
 // #define DISTRHO_PLUGIN_LV2_CATEGORY       "lv2:AnalyserPlugin"
 // #define DISTRHO_PLUGIN_VST3_CATEGORIES    "Fx|Analyzer"
-#define DISTRHO_UI_USE_NANOVG             1
-#define DISTRHO_UI_USER_RESIZABLE         1
 
 enum Parameters {
     kParameterCount
diff --git a/src/Makefile b/src/Makefile
index 2f1ba6b..64a3590 100644
--- a/src/Makefile
+++ b/src/Makefile
@@ -28,14 +28,17 @@ FILES_DSP = \
 	override/library.cpp \
 	override/network.cpp
 
-# override/osdialog.cpp
-# override/RemoteNanoVG.cpp
-# override/RemoteWindow.cpp
-
+ifeq ($(HEADLESS),true)
+FILES_DSP += \
+	override/osdialog.cpp \
+	override/RemoteNanoVG.cpp \
+	override/RemoteWindow.cpp
+else
 FILES_UI = \
 	CardinalUI.cpp \
 	override/MenuBar.cpp \
 	override/Window.cpp
+endif
 
 # --------------------------------------------------------------
 # Import base definitions
@@ -143,6 +146,10 @@ BASE_FLAGS += -I../include/mingw-compat
 BASE_FLAGS += -I../include/mingw-std-threads
 endif
 
+ifeq ($(HEADLESS),true)
+BASE_FLAGS += -DHEADLESS
+endif
+
 ifeq ($(WITH_LTO),true)
 BASE_FLAGS += -fno-strict-aliasing -flto
 endif
diff --git a/src/override/RemoteNanoVG.cpp b/src/override/RemoteNanoVG.cpp
index 3a8027b..15f639d 100644
--- a/src/override/RemoteNanoVG.cpp
+++ b/src/override/RemoteNanoVG.cpp
@@ -15,16 +15,23 @@
  * For a full copy of the GNU General Public License see the LICENSE file.
  */
 
+#ifndef HEADLESS
 #include "OpenGL.hpp"
+#endif
 
 #include "src/nanovg/nanovg.h"
 
-#define NANOVG_GL2_IMPLEMENTATION
-// #define NANOVG_GLES2_IMPLEMENTATION
-#include "src/nanovg/nanovg_gl.h"
-
-#define NANOVG_FBO_VALID 1
-#include "src/nanovg/nanovg_gl_utils.h"
+#ifdef HEADLESS
+struct NVGLUframebuffer;
+void nvgluBindFramebuffer(NVGLUframebuffer* fb) {}
+NVGLUframebuffer* nvgluCreateFramebuffer(NVGcontext* ctx, int w, int h, int imageFlags) { return nullptr; }
+void nvgluDeleteFramebuffer(NVGLUframebuffer* fb) {}
+#else
+# define NANOVG_GLES2_IMPLEMENTATION
+# define NANOVG_FBO_VALID 1
+# include "src/nanovg/nanovg_gl.h"
+# include "src/nanovg/nanovg_gl_utils.h"
+#endif
 
 #if defined(__GNUC__) && (__GNUC__ >= 6)
 # pragma GCC diagnostic push
@@ -38,18 +45,6 @@
 # pragma GCC diagnostic pop
 #endif
 
-// typedef struct NVGLUframebuffer {
-// 	NVGcontext* ctx;
-// 	GLuint fbo;
-// 	GLuint rbo;
-// 	GLuint texture;
-// 	int image;
-// } NVGLUframebuffer;
-//
-// void nvgluBindFramebuffer(NVGLUframebuffer* fb) {}
-// NVGLUframebuffer* nvgluCreateFramebuffer(NVGcontext* ctx, int w, int h, int imageFlags) { return nullptr; }
-// void nvgluDeleteFramebuffer(NVGLUframebuffer* fb) {}
-
 #define GLFWAPI
 
 extern "C" {
@@ -63,5 +58,7 @@ GLFWAPI int glfwGetKeyScancode(int key) { return 0; }
 
 }
 
-#define STB_IMAGE_WRITE_IMPLEMENTATION
-#include "../src/Rack/dep/glfw/deps/stb_image_write.h"
+#ifndef HEADLESS
+# define STB_IMAGE_WRITE_IMPLEMENTATION
+# include "../src/Rack/dep/glfw/deps/stb_image_write.h"
+#endif
diff --git a/src/override/RemoteWindow.cpp b/src/override/RemoteWindow.cpp
index 65ca0b6..5c95a0c 100644
--- a/src/override/RemoteWindow.cpp
+++ b/src/override/RemoteWindow.cpp
@@ -25,15 +25,10 @@
  * the License, or (at your option) any later version.
  */
 
-#define NANOVG_GL2 1
-
 #include <map>
 #include <queue>
 #include <thread>
 
-#include "../src/Rack/dep/glfw/deps/stb_image_write.h"
-#include <GL/osmesa.h>
-
 #include <window/Window.hpp>
 #include <asset.hpp>
 #include <widget/Widget.hpp>
@@ -49,9 +44,24 @@
 #endif
 
 #include "DistrhoPlugin.hpp"
-#include "extra/Thread.hpp"
 #include "../WindowParameters.hpp"
 
+#ifndef HEADLESS
+# include "../src/Rack/dep/glfw/deps/stb_image_write.h"
+# include "extra/Thread.hpp"
+# include <GL/osmesa.h>
+#endif
+
+
+#ifdef HEADLESS
+namespace rack {
+namespace app {
+widget::Widget* createMenuBar() { return new widget::Widget; }
+}
+}
+#endif
+
+
 namespace rack {
 namespace window {
 
@@ -103,14 +113,20 @@ struct WindowParams {
 	float rackBrightness = 1.0f;
 };
 
-struct Window::Internal : public Thread {
+struct Window::Internal
+#ifndef HEADLESS
+    : public Thread
+#endif
+{
 	DISTRHO_NAMESPACE::Plugin* plugin = nullptr;
 	DISTRHO_NAMESPACE::WindowParameters params;
 	DISTRHO_NAMESPACE::WindowParametersCallback* callback = nullptr;
 	Context* context = nullptr;
 	Window* self = nullptr;
+#ifndef HEADLESS
 	OSMesaContext mesa = nullptr;
 	GLubyte* mesaBuffer = nullptr;
+#endif
 
 	math::Vec size = minWindowSize;
 	std::string lastWindowTitle;
@@ -127,6 +143,7 @@ struct Window::Internal : public Thread {
 
 	bool fbDirtyOnSubpixelChange = true;
 
+#ifndef HEADLESS
 	void run() override {
 		self->run();
 		int i=0;
@@ -146,6 +163,7 @@ struct Window::Internal : public Thread {
 		}
 		d_stdout("thread quit");
 	}
+#endif
 };
 
 Window::Window() {
@@ -154,6 +172,7 @@ Window::Window() {
 	internal->self = this;
 }
 
+#ifndef HEADLESS
 static void flipBitmap(uint8_t* pixels, int width, int height, int depth) {
 	for (int y = 0; y < height / 2; y++) {
 		int flipY = height - y - 1;
@@ -163,11 +182,13 @@ static void flipBitmap(uint8_t* pixels, int width, int height, int depth) {
 		std::memcpy(&pixels[flipY * width * depth], tmp, width * depth);
 	}
 }
+#endif
 
 void WindowInit(Window* const window, DISTRHO_NAMESPACE::Plugin* const plugin)
 {
 	window->internal->plugin = plugin;
 
+#ifndef HEADLESS
 	window->internal->mesa = OSMesaCreateContextExt(OSMESA_RGBA, 24, 8, 0, nullptr);
 	DISTRHO_SAFE_ASSERT_RETURN(window->internal->mesa != nullptr,);
 
@@ -196,6 +217,7 @@ void WindowInit(Window* const window, DISTRHO_NAMESPACE::Plugin* const plugin)
 // 	window->vg = nvgCreateGLES2(nvgFlags);
 // 	window->fbVg = nvgCreateSharedGLES2(window->vg, nvgFlags);
 // #endif
+#endif
 
 	// Load default Blendish font
 	window->uiFont = window->loadFont(asset::system("res/fonts/DejaVuSans.ttf"));
@@ -210,6 +232,7 @@ void WindowInit(Window* const window, DISTRHO_NAMESPACE::Plugin* const plugin)
 		APP->scene->onContextCreate(e);
 	}
 
+#ifndef HEADLESS
 	d_stdout("all good with mesa and GL? %d | %p %p %p", ok, window->internal->mesa, window->vg, window->fbVg);
 	// window->internal->startThread();
 
@@ -277,6 +300,7 @@ void WindowInit(Window* const window, DISTRHO_NAMESPACE::Plugin* const plugin)
 	delete[] pixels;
 
 	d_stdout("idle - after png");
+#endif
 }
 
 void WindowMods(Window* const window, const int mods)
@@ -296,6 +320,7 @@ Window::~Window() {
 	internal->fontCache.clear();
 	internal->imageCache.clear();
 
+#ifndef HEADLESS
 // #if defined NANOVG_GL2
 	nvgDeleteGL2(vg);
 	nvgDeleteGL2(fbVg);
@@ -310,6 +335,8 @@ Window::~Window() {
 		OSMesaDestroyContext(internal->mesa);
 
 	delete[] internal->mesaBuffer;
+#endif
+
 	delete internal;
 }
 
diff --git a/src/override/common.cpp b/src/override/common.cpp
index fe80771..1161457 100644
--- a/src/override/common.cpp
+++ b/src/override/common.cpp
@@ -15,6 +15,16 @@
  * For a full copy of the GNU General Public License see the LICENSE file.
  */
 
+/**
+ * This file is an edited version of VCVRack's common.cpp
+ * Copyright (C) 2016-2021 VCV.
+ *
+ * This program is free software: you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 3 of
+ * the License, or (at your option) any later version.
+ */
+
 #include <common.hpp>
 #include <string.hpp>
 
diff --git a/src/override/context.cpp b/src/override/context.cpp
index 3efdb25..f3c6cd6 100644
--- a/src/override/context.cpp
+++ b/src/override/context.cpp
@@ -8,6 +8,16 @@
 
 #include "DistrhoPluginUtils.hpp"
 
+/**
+ * This file is an edited version of VCVRack's context.cpp
+ * Copyright (C) 2016-2021 VCV.
+ *
+ * This program is free software: you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 3 of
+ * the License, or (at your option) any later version.
+ */
+
 
 namespace rack {
 
diff --git a/src/override/dep.cpp b/src/override/dep.cpp
index 1e389ae..8fd9e03 100644
--- a/src/override/dep.cpp
+++ b/src/override/dep.cpp
@@ -15,7 +15,7 @@
  * For a full copy of the GNU General Public License see the LICENSE file.
  */
 
-#include "OpenGL.hpp"
+#include <cstdio>
 
 // fix blendish build, missing symbol in debug mode
 #ifdef DEBUG