diff --git a/src/kekengine/cpp/ui.cpp b/src/kekengine/cpp/ui.cpp
new file mode 100644
index 0000000..3fab951
--- /dev/null
+++ b/src/kekengine/cpp/ui.cpp
@@ -0,0 +1 @@
+#include "ui.h"
diff --git a/src/kekengine/include/input.h b/src/kekengine/include/input.h
index d1c2ff5..b81f830 100644
--- a/src/kekengine/include/input.h
+++ b/src/kekengine/include/input.h
@@ -15,6 +15,7 @@ typedef unsigned int InputListener;
 typedef unsigned int GLFWKey;
 typedef unsigned int GLFWKeyState;
 typedef unsigned int KeyMapping;
+typedef unsigned int GLFWMouseButton;
 
 struct KeyMappingData {
 	std::string name;
diff --git a/src/kekengine/include/ui.h b/src/kekengine/include/ui.h
new file mode 100644
index 0000000..5de9a08
--- /dev/null
+++ b/src/kekengine/include/ui.h
@@ -0,0 +1,198 @@
+#pragma once
+
+#include <glm/glm.hpp>
+#include <string>
+
+#include "fonts.h"
+#include "input.h"
+
+#define px(val) UIValue(val, UIUnit::PIXELS)
+#define pw(val) UIValue(val, UIUnit::PARENT_WIDTH)
+#define ph(val) UIValue(val, UIUnit::PARENT_HEIGHT)
+#define sw(val) UIValue(val, UIUnit::SCREEN_WIDTH)
+#define sh(val) UIValue(val, UIUnit::SCREEN_HEIGHT)
+
+namespace kek {
+
+struct UIBounds {
+	int x, y, w, h;
+	UIBounds(int x, int y, int w, int h) {
+		this->x = x;
+		this->y = y;
+		this->w = w;
+		this->h = h;
+	}
+};
+
+struct UIPoint {
+	int x, y;
+	UIPoint(int x, int y) {
+		this->x = x;
+		this->y = y;
+	}
+};
+
+enum class UIElementType {
+	RECTANGLE,
+	TEXT,
+	BUTTON,
+	TEXTURE,
+	TEXT_FIELD,
+	SLIDER,
+	CHECKBOX,
+	GROUP
+};
+
+enum class TextMode {
+	// Draw with y as baseline, disables vertical offset from the origin position specified using setOrigin()
+	BASELINE,
+	// Draw from the set origin
+	ORIGIN
+};
+
+enum class TextBounds {
+	SMALLEST,
+	LINE
+};
+
+enum class SliderDirection {
+	HORIZONTAL,
+	VERTICAL
+};
+
+enum class Origin {
+	TOP_LEFT,
+	TOP_CENTER,
+	TOP_RIGHT,
+	BOTTOM_LEFT,
+	BOTTOM_CENTER,
+	BOTTOM_RIGHT,
+	LEFT_CENTER,
+	RIGHT_CENTER,
+	CENTER
+};
+
+enum class UIUnit {
+	PIXELS,
+	PARENT_WIDTH,
+	PARENT_HEIGHT,
+	SCREEN_WIDTH,
+	SCREEN_HEIGHT
+};
+
+struct UIValue {
+	float pixels = 0;
+	float parentWidth = 0;
+	float parentHeight = 0;
+	float screenWidth = 0;
+	float screenHeight = 0;
+
+	constexpr UIValue(float value, UIUnit unit) {
+		switch(unit) {
+			case UIUnit::PIXELS:
+				this->pixels = value;
+				break;
+			case UIUnit::PARENT_WIDTH:
+				this->parentWidth = value;
+				break;
+			case UIUnit::PARENT_HEIGHT:
+				this->parentHeight = value;
+				break;
+			case UIUnit::SCREEN_WIDTH:
+				this->screenWidth = value;
+				break;
+			case UIUnit::SCREEN_HEIGHT:
+				this->screenHeight = value;
+				break;
+		}
+	}
+
+	constexpr UIValue() = default;
+
+	constexpr UIValue &operator+=(const UIValue &rhs);
+
+	constexpr UIValue &operator-=(const UIValue &rhs);
+
+	constexpr friend UIValue operator+(const UIValue &lhs, const UIValue &rhs);
+
+	constexpr friend UIValue operator-(const UIValue &lhs, const UIValue &rhs);
+
+};
+
+class UIElement {
+
+protected:
+	static Font *defaultFont;
+
+	UIElement *parent = nullptr;
+	std::vector<UIElement *> children;
+
+public:
+	UIValue x, y;
+	Origin origin = Origin::TOP_LEFT;
+	bool clickable = false;
+	bool hovering = false;
+	bool visible = true;
+	bool focusable = false;
+	bool draggable = false;
+
+	UIElement(UIValue x, UIValue y);
+
+	virtual ~UIElement();
+
+	virtual UIElementType getType() = 0;
+
+	// Returns the element's position relative to its parent in pixels
+	UIPoint getPosition();
+
+	// Returns the element's position on the screen in pixels
+	UIPoint getScreenPosition();
+
+	void addChild(UIElement *child);
+
+	void removeChild(UIElement *child);
+
+protected:
+	inline int uiToScreen(UIValue val);
+
+public:
+	// Returns the bounds of the element relative to its origin (as returned by getX() and getY())
+	virtual UIBounds getBounds() = 0;
+
+	void drawAll(UIPoint screenPos, glm::mat4 projection);
+
+	virtual void draw(UIPoint screenPos, glm::mat4 projection) = 0;
+
+	void hoverAll(UIPoint pos, UIPoint screenPos);
+
+	void hoverExitAll();
+
+	virtual void hoverEnter(UIPoint pos, UIPoint screenPos) {};
+
+	virtual void hover(UIPoint pos, UIPoint screenPos) {};
+
+	virtual void hoverExit() {};
+
+	void clickAll(UIPoint pos, UIPoint screenPos, GLFWMouseButton button);
+
+	virtual void click(UIPoint pos, UIPoint screenPos, GLFWMouseButton button) {};
+
+	bool focusEnterAll(UIPoint pos);
+
+	virtual void focusEnter(UIPoint pos, UIPoint screenPos) {};
+
+	virtual void focusExit() {};
+
+	UIElement *dragEnterAll(UIPoint pos, UIPoint screenPos);
+
+	virtual void dragEnter(UIPoint pos, UIPoint screenPos) {};
+
+	virtual void drag(UIPoint pos, UIPoint screenPos) {};
+
+	virtual void dragExit(UIPoint pos, UIPoint screenPos) {};
+
+	static void init();
+
+};
+
+}