diff --git a/keyboards/haverworks/theseus75/config.h b/keyboards/haverworks/theseus75/config.h
new file mode 100644
index 00000000000..7627837e766
--- /dev/null
+++ b/keyboards/haverworks/theseus75/config.h
@@ -0,0 +1,33 @@
+// Copyright 2023 Moritz Plattner (@ebastler), Alex Havermale (@haversnail)
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+#pragma once
+
+/* Defines for configuring the serial driver for split comms (see https://docs.qmk.fm/drivers/serial) */
+#define SERIAL_USART_DRIVER SD3    // USART 3
+
+/* Defines for required pins */
+#define ID_PIN A13
+#define USBSW_PIN A14     // Switches the hub input/output with the MUXes
+#define PSW_PIN A15       // Turns the power routing to the USB-C port on/off
+#define BUS_B_PIN C13     // Tells the hub to be bus-powered or self-powered (which in turn tells the clients to use 100 mA or 500 mA)
+#define USB_VBUS_PIN C15  // Only the master side will have VBUS present at power-up (used to determine master/slave)
+#define USBPD_1_PIN F0
+#define USBPD_2_PIN F1
+
+/* Additional defines for managing power and state scross split */
+#define DISABLE_BUS_POWER_MODE TRUE
+#define KB_STATE_SYNC_INTERVAL 500
+#define USBPD_ALLOWANCE_CHECK_INTERVAL 100
+#define SPLIT_TRANSACTION_IDS_KB RPC_ID_KB_STATE
+
+/* Defines for the RGB matrix */
+#define INDICATOR_MAX_BRIGHTNESS 255
+#define CAPS_LOCK_LED_INDEX 0 // LED1 on PCB
+#define WS2812_EXTERNAL_PULLUP
+#define WS2812_PWM_DRIVER PWMD3
+#define WS2812_PWM_CHANNEL 4
+#define WS2812_PWM_PAL_MODE 10
+#define WS2812_DMA_STREAM STM32_DMA1_STREAM2
+#define WS2812_DMA_CHANNEL 2
+#define WS2812_DMAMUX_ID STM32_DMAMUX1_TIM3_UP
diff --git a/keyboards/haverworks/theseus75/halconf.h b/keyboards/haverworks/theseus75/halconf.h
new file mode 100644
index 00000000000..e7da7271bb4
--- /dev/null
+++ b/keyboards/haverworks/theseus75/halconf.h
@@ -0,0 +1,10 @@
+// Copyright 2023 Moritz Plattner (@ebastler)
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+#pragma once
+
+#define HAL_USE_SERIAL TRUE
+
+#define HAL_USE_PWM TRUE
+
+#include_next <halconf.h>
diff --git a/keyboards/haverworks/theseus75/keyboard.json b/keyboards/haverworks/theseus75/keyboard.json
new file mode 100644
index 00000000000..60f791ae9d7
--- /dev/null
+++ b/keyboards/haverworks/theseus75/keyboard.json
@@ -0,0 +1,456 @@
+{
+    "manufacturer": "Haverworks",
+    "keyboard_name": "Theseus75",
+    "maintainer": "ebastler",
+    "bootloader": "stm32-dfu",
+    "bootmagic": {
+        "matrix": [0, 1]
+    },
+    "diode_direction": "COL2ROW",
+    "encoder": {
+        "rotary": [
+            {"pin_a": "A8", "pin_b": "C6", "resolution": 2}
+        ]
+    },
+    "features": {
+        "bootmagic": true,
+        "encoder": true,
+        "extrakey": true,
+        "mousekey": true,
+        "nkro": true,
+        "rgb_matrix": true
+    },
+    "matrix_pins": {
+        "cols": ["B11", "C14", "B6", "B5", "B4", "B3", "C11", "C10", null],
+        "rows": ["A9", "A10", "B15", "B12", "B13", "B14"]
+    },
+    "processor": "STM32G431",
+    "rgb_matrix": {
+        "animations": {
+            "alphas_mods": true,
+            "band_pinwheel_sat": true,
+            "band_pinwheel_val": true,
+            "band_sat": true,
+            "band_spiral_sat": true,
+            "band_spiral_val": true,
+            "band_val": true,
+            "breathing": true,
+            "cycle_all": true,
+            "cycle_left_right": true,
+            "cycle_out_in": true,
+            "cycle_out_in_dual": true,
+            "cycle_pinwheel": true,
+            "cycle_spiral": true,
+            "cycle_up_down": true,
+            "dual_beacon": true,
+            "gradient_left_right": true,
+            "gradient_up_down": true,
+            "hue_breathing": true,
+            "hue_pendulum": true,
+            "hue_wave": true,
+            "jellybean_raindrops": true,
+            "pixel_flow": true,
+            "pixel_fractal": true,
+            "pixel_rain": true,
+            "rainbow_beacon": true,
+            "rainbow_moving_chevron": true,
+            "rainbow_pinwheels": true,
+            "raindrops": true
+        },
+        "driver": "ws2812",
+        "layout": [
+            {"matrix": [3, 1], "x": 32, "y": 34, "flags": 8},
+            {"x": 28, "y": 1, "flags": 2},
+            {"x": 43, "y": 1, "flags": 2},
+            {"x": 56, "y": 1, "flags": 2},
+            {"x": 69, "y": 1, "flags": 2},
+            {"x": 84, "y": 1, "flags": 2},
+            {"x": 99, "y": 1, "flags": 2},
+            {"x": 97, "y": 8, "flags": 2},
+            {"x": 91, "y": 19, "flags": 2},
+            {"x": 91, "y": 31, "flags": 2},
+            {"x": 92, "y": 42, "flags": 2},
+            {"x": 96, "y": 53, "flags": 2},
+            {"x": 97, "y": 64, "flags": 2},
+            {"x": 81, "y": 64, "flags": 2},
+            {"x": 66, "y": 64, "flags": 2},
+            {"x": 53, "y": 64, "flags": 2},
+            {"x": 40, "y": 64, "flags": 2},
+            {"x": 26, "y": 64, "flags": 2},
+            {"x": 13, "y": 64, "flags": 2},
+            {"x": 0, "y": 64, "flags": 2},
+            {"x": 0, "y": 53, "flags": 2},
+            {"x": 0, "y": 42, "flags": 2},
+            {"x": 0, "y": 31, "flags": 2},
+            {"x": 0, "y": 19, "flags": 2},
+            {"x": 0, "y": 9, "flags": 2},
+            {"x": 0, "y": 1, "flags": 2},
+            {"x": 13, "y": 1, "flags": 2},
+            {"x": 224, "y": 31, "flags": 2},
+            {"x": 224, "y": 42, "flags": 2},
+            {"x": 224, "y": 53, "flags": 2},
+            {"x": 224, "y": 64, "flags": 2},
+            {"x": 209, "y": 64, "flags": 2},
+            {"x": 194, "y": 64, "flags": 2},
+            {"x": 180, "y": 64, "flags": 2},
+            {"x": 165, "y": 64, "flags": 2},
+            {"x": 152, "y": 64, "flags": 2},
+            {"x": 138, "y": 64, "flags": 2},
+            {"x": 124, "y": 64, "flags": 2},
+            {"x": 124, "y": 53, "flags": 2},
+            {"x": 119, "y": 42, "flags": 2},
+            {"x": 114, "y": 31, "flags": 2},
+            {"x": 117, "y": 19, "flags": 2},
+            {"x": 122, "y": 8, "flags": 2},
+            {"x": 126, "y": 1, "flags": 2},
+            {"x": 140, "y": 1, "flags": 2},
+            {"x": 155, "y": 1, "flags": 2},
+            {"x": 168, "y": 1, "flags": 2},
+            {"x": 181, "y": 1, "flags": 2},
+            {"x": 196, "y": 1, "flags": 2},
+            {"x": 211, "y": 1, "flags": 2},
+            {"x": 224, "y": 1, "flags": 2},
+            {"x": 224, "y": 8, "flags": 2},
+            {"x": 224, "y": 19, "flags": 2}
+        ],
+        "max_brightness": 128,
+        "sleep": true,
+        "split_count": [27, 26]
+    },
+    "split": {
+        "bootmagic": {
+            "matrix": [6, 6]
+        },
+        "enabled": true,
+        "encoder": {
+            "right": {
+                "rotary": [
+                    {"pin_a": "B5", "pin_b": "B4", "resolution": 2}
+                ]
+            }
+        },
+        "handedness": {
+            "pin": "B9"
+        },
+        "matrix_pins": {
+            "right": {
+                "cols": ["A10", "A9", "A8", "C6", "B15", "B14", "B13", "B12", "C14"],
+                "rows": ["B3", "C10", "C11", "A1", "A0", "B6"]
+            }
+        },
+        "serial": {
+            "driver": "usart",
+            "pin": "B10"
+        },
+        "soft_serial_speed": 0,
+        "transport": {
+            "sync": {
+                "indicators": true,
+                "layer_state": true,
+                "matrix_state": true
+            },
+            "watchdog": true
+        }
+    },
+    "url": "https://haver.works/theseus75",
+    "usb": {
+        "device_version": "1.0.0",
+        "pid": "0x0001",
+        "vid": "0x6877"
+    },
+    "ws2812": {
+        "driver": "pwm",
+        "pin": "B7"
+    },
+    "layouts": {
+        "LAYOUT_all": {
+            "layout": [
+                {"label": "LENC", "matrix": [0, 0], "x": 0, "y": 0},
+                {"label": "ESC", "matrix": [0, 1], "x": 1.5, "y": 0},
+                {"label": "F1", "matrix": [0, 2], "x": 2.75, "y": 0},
+                {"label": "F2", "matrix": [0, 3], "x": 3.75, "y": 0},
+                {"label": "F3", "matrix": [0, 4], "x": 4.75, "y": 0},
+                {"label": "F4", "matrix": [0, 5], "x": 5.75, "y": 0},
+                {"label": "F5", "matrix": [0, 6], "x": 7, "y": 0},
+                {"label": "F6", "matrix": [0, 7], "x": 8, "y": 0},
+                {"label": "F7", "matrix": [6, 0], "x": 10, "y": 0},
+                {"label": "F8", "matrix": [6, 1], "x": 11, "y": 0},
+                {"label": "F9", "matrix": [6, 2], "x": 12.25, "y": 0},
+                {"label": "F10", "matrix": [6, 3], "x": 13.25, "y": 0},
+                {"label": "F11", "matrix": [6, 4], "x": 14.25, "y": 0},
+                {"label": "F12", "matrix": [6, 5], "x": 15.25, "y": 0},
+                {"label": "F13", "matrix": [6, 6], "x": 16.5, "y": 0},
+                {"label": "RENC", "matrix": [6, 8], "x": 18, "y": 0},
+                {"label": "M1", "matrix": [1, 0], "x": 0, "y": 1},
+                {"label": "GRAV", "matrix": [1, 1], "x": 1.5, "y": 1},
+                {"label": "1", "matrix": [1, 2], "x": 2.5, "y": 1},
+                {"label": "2", "matrix": [1, 3], "x": 3.5, "y": 1},
+                {"label": "3", "matrix": [1, 4], "x": 4.5, "y": 1},
+                {"label": "4", "matrix": [1, 5], "x": 5.5, "y": 1},
+                {"label": "5", "matrix": [1, 6], "x": 6.5, "y": 1},
+                {"label": "6", "matrix": [1, 7], "x": 7.5, "y": 1},
+                {"label": "7", "matrix": [7, 0], "x": 9.5, "y": 1},
+                {"label": "8", "matrix": [7, 1], "x": 10.5, "y": 1},
+                {"label": "9", "matrix": [7, 2], "x": 11.5, "y": 1},
+                {"label": "0", "matrix": [7, 3], "x": 12.5, "y": 1},
+                {"label": "-", "matrix": [7, 4], "x": 13.5, "y": 1},
+                {"label": "=", "matrix": [7, 5], "x": 14.5, "y": 1},
+                {"label": "Back", "matrix": [7, 6], "x": 15.5, "y": 1},
+                {"label": "Del", "matrix": [7, 7], "x": 16.5, "y": 1},
+                {"label": "Home", "matrix": [7, 8], "x": 18, "y": 1},
+                {"label": "M2", "matrix": [2, 0], "x": 0, "y": 2},
+                {"label": "Tab", "matrix": [2, 1], "x": 1.5, "y": 2, "w": 1.5},
+                {"label": "Q", "matrix": [2, 3], "x": 3, "y": 2},
+                {"label": "W", "matrix": [2, 4], "x": 4, "y": 2},
+                {"label": "E", "matrix": [2, 5], "x": 5, "y": 2},
+                {"label": "R", "matrix": [2, 6], "x": 6, "y": 2},
+                {"label": "T", "matrix": [2, 7], "x": 7, "y": 2},
+                {"label": "Y", "matrix": [8, 0], "x": 9, "y": 2},
+                {"label": "U", "matrix": [8, 1], "x": 10, "y": 2},
+                {"label": "I", "matrix": [8, 2], "x": 11, "y": 2},
+                {"label": "O", "matrix": [8, 3], "x": 12, "y": 2},
+                {"label": "P", "matrix": [8, 4], "x": 13, "y": 2},
+                {"label": "[", "matrix": [8, 5], "x": 14, "y": 2},
+                {"label": "]", "matrix": [8, 6], "x": 15, "y": 2},
+                {"label": "BSLS", "matrix": [8, 7], "x": 16, "y": 2, "w": 1.5},
+                {"label": "PgUp", "matrix": [8, 8], "x": 18, "y": 2},
+                {"label": "M3", "matrix": [3, 0], "x": 0, "y": 3},
+                {"label": "Caps", "matrix": [3, 1], "x": 1.5, "y": 3, "w": 1.75},
+                {"label": "A", "matrix": [3, 3], "x": 3.25, "y": 3},
+                {"label": "S", "matrix": [3, 4], "x": 4.25, "y": 3},
+                {"label": "D", "matrix": [3, 5], "x": 5.25, "y": 3},
+                {"label": "F", "matrix": [3, 6], "x": 6.25, "y": 3},
+                {"label": "G", "matrix": [3, 7], "x": 7.25, "y": 3},
+                {"label": "H", "matrix": [9, 0], "x": 9.25, "y": 3},
+                {"label": "J", "matrix": [9, 1], "x": 10.25, "y": 3},
+                {"label": "K", "matrix": [9, 2], "x": 11.25, "y": 3},
+                {"label": "L", "matrix": [9, 3], "x": 12.25, "y": 3},
+                {"label": ";", "matrix": [9, 4], "x": 13.25, "y": 3},
+                {"label": "'", "matrix": [9, 5], "x": 14.25, "y": 3},
+                {"label": "NUHS", "matrix": [9, 6], "x": 15.25, "y": 3},
+                {"label": "Enter", "matrix": [9, 7], "x": 16.25, "y": 3, "w": 1.25},
+                {"label": "PgDn", "matrix": [9, 8], "x": 18, "y": 3},
+                {"label": "M4", "matrix": [4, 0], "x": 0, "y": 4},
+                {"label": "Shift", "matrix": [4, 1], "x": 1.5, "y": 4, "w": 1.25},
+                {"label": "NUBS", "matrix": [4, 2], "x": 2.75, "y": 4},
+                {"label": "Z", "matrix": [4, 3], "x": 3.75, "y": 4},
+                {"label": "X", "matrix": [4, 4], "x": 4.75, "y": 4},
+                {"label": "C", "matrix": [4, 5], "x": 5.75, "y": 4},
+                {"label": "V", "matrix": [4, 6], "x": 6.75, "y": 4},
+                {"label": "B", "matrix": [4, 7], "x": 7.75, "y": 4},
+                {"label": "N", "matrix": [10, 0], "x": 9.75, "y": 4},
+                {"label": "M", "matrix": [10, 1], "x": 10.75, "y": 4},
+                {"label": ",", "matrix": [10, 2], "x": 11.75, "y": 4},
+                {"label": ".", "matrix": [10, 3], "x": 12.75, "y": 4},
+                {"label": "/", "matrix": [10, 4], "x": 13.75, "y": 4},
+                {"label": "Shift", "matrix": [10, 6], "x": 14.75, "y": 4, "w": 1.75},
+                {"label": "Up", "matrix": [10, 7], "x": 16.75, "y": 4},
+                {"label": "End", "matrix": [10, 8], "x": 18, "y": 4},
+                {"label": "M5", "matrix": [5, 0], "x": 0, "y": 5},
+                {"label": "Ctrl", "matrix": [5, 1], "x": 1.5, "y": 5, "w": 1.25},
+                {"label": "Gui", "matrix": [5, 2], "x": 2.75, "y": 5, "w": 1.25},
+                {"label": "Alt", "matrix": [5, 3], "x": 4, "y": 5, "w": 1.25},
+                {"label": "Space", "matrix": [5, 4], "x": 5.25, "y": 5, "w": 2.25},
+                {"label": "FN", "matrix": [5, 7], "x": 7.5, "y": 5, "w": 1.25},
+                {"label": "Space", "matrix": [11, 1], "x": 9.75, "y": 5, "w": 2.75},
+                {"label": "Alt", "matrix": [11, 3], "x": 12.5, "y": 5},
+                {"label": "Gui", "matrix": [11, 4], "x": 13.5, "y": 5},
+                {"label": "Ctrl", "matrix": [11, 5], "x": 14.5, "y": 5},
+                {"label": "Left", "matrix": [11, 6], "x": 15.75, "y": 5},
+                {"label": "Down", "matrix": [11, 7], "x": 16.75, "y": 5},
+                {"label": "Rght", "matrix": [11, 8], "x": 17.75, "y": 5}
+            ]
+        },
+        "LAYOUT_ansi": {
+            "layout": [
+                {"label": "LENC", "matrix": [0, 0], "x": 0, "y": 0},
+                {"label": "ESC", "matrix": [0, 1], "x": 1.5, "y": 0},
+                {"label": "F1", "matrix": [0, 2], "x": 2.75, "y": 0},
+                {"label": "F2", "matrix": [0, 3], "x": 3.75, "y": 0},
+                {"label": "F3", "matrix": [0, 4], "x": 4.75, "y": 0},
+                {"label": "F4", "matrix": [0, 5], "x": 5.75, "y": 0},
+                {"label": "F5", "matrix": [0, 6], "x": 7, "y": 0},
+                {"label": "F6", "matrix": [0, 7], "x": 8, "y": 0},
+                {"label": "F7", "matrix": [6, 0], "x": 10, "y": 0},
+                {"label": "F8", "matrix": [6, 1], "x": 11, "y": 0},
+                {"label": "F9", "matrix": [6, 2], "x": 12.25, "y": 0},
+                {"label": "F10", "matrix": [6, 3], "x": 13.25, "y": 0},
+                {"label": "F11", "matrix": [6, 4], "x": 14.25, "y": 0},
+                {"label": "F12", "matrix": [6, 5], "x": 15.25, "y": 0},
+                {"label": "F13", "matrix": [6, 6], "x": 16.5, "y": 0},
+                {"label": "RENC", "matrix": [6, 8], "x": 18, "y": 0},
+                {"label": "M1", "matrix": [1, 0], "x": 0, "y": 1},
+                {"label": "GRAV", "matrix": [1, 1], "x": 1.5, "y": 1},
+                {"label": "1", "matrix": [1, 2], "x": 2.5, "y": 1},
+                {"label": "2", "matrix": [1, 3], "x": 3.5, "y": 1},
+                {"label": "3", "matrix": [1, 4], "x": 4.5, "y": 1},
+                {"label": "4", "matrix": [1, 5], "x": 5.5, "y": 1},
+                {"label": "5", "matrix": [1, 6], "x": 6.5, "y": 1},
+                {"label": "6", "matrix": [1, 7], "x": 7.5, "y": 1},
+                {"label": "7", "matrix": [7, 0], "x": 9.5, "y": 1},
+                {"label": "8", "matrix": [7, 1], "x": 10.5, "y": 1},
+                {"label": "9", "matrix": [7, 2], "x": 11.5, "y": 1},
+                {"label": "0", "matrix": [7, 3], "x": 12.5, "y": 1},
+                {"label": "-", "matrix": [7, 4], "x": 13.5, "y": 1},
+                {"label": "=", "matrix": [7, 5], "x": 14.5, "y": 1},
+                {"label": "Back", "matrix": [7, 6], "x": 15.5, "y": 1, "w": 2},
+                {"label": "Home", "matrix": [7, 8], "x": 18, "y": 1},
+                {"label": "M2", "matrix": [2, 0], "x": 0, "y": 2},
+                {"label": "Tab", "matrix": [2, 1], "x": 1.5, "y": 2, "w": 1.5},
+                {"label": "Q", "matrix": [2, 3], "x": 3, "y": 2},
+                {"label": "W", "matrix": [2, 4], "x": 4, "y": 2},
+                {"label": "E", "matrix": [2, 5], "x": 5, "y": 2},
+                {"label": "R", "matrix": [2, 6], "x": 6, "y": 2},
+                {"label": "T", "matrix": [2, 7], "x": 7, "y": 2},
+                {"label": "Y", "matrix": [8, 0], "x": 9, "y": 2},
+                {"label": "U", "matrix": [8, 1], "x": 10, "y": 2},
+                {"label": "I", "matrix": [8, 2], "x": 11, "y": 2},
+                {"label": "O", "matrix": [8, 3], "x": 12, "y": 2},
+                {"label": "P", "matrix": [8, 4], "x": 13, "y": 2},
+                {"label": "[", "matrix": [8, 5], "x": 14, "y": 2},
+                {"label": "]", "matrix": [8, 6], "x": 15, "y": 2},
+                {"label": "BSLS", "matrix": [8, 7], "x": 16, "y": 2, "w": 1.5},
+                {"label": "PgUp", "matrix": [8, 8], "x": 18, "y": 2},
+                {"label": "M3", "matrix": [3, 0], "x": 0, "y": 3},
+                {"label": "Caps", "matrix": [3, 1], "x": 1.5, "y": 3, "w": 1.75},
+                {"label": "A", "matrix": [3, 3], "x": 3.25, "y": 3},
+                {"label": "S", "matrix": [3, 4], "x": 4.25, "y": 3},
+                {"label": "D", "matrix": [3, 5], "x": 5.25, "y": 3},
+                {"label": "F", "matrix": [3, 6], "x": 6.25, "y": 3},
+                {"label": "G", "matrix": [3, 7], "x": 7.25, "y": 3},
+                {"label": "H", "matrix": [9, 0], "x": 9.25, "y": 3},
+                {"label": "J", "matrix": [9, 1], "x": 10.25, "y": 3},
+                {"label": "K", "matrix": [9, 2], "x": 11.25, "y": 3},
+                {"label": "L", "matrix": [9, 3], "x": 12.25, "y": 3},
+                {"label": ";", "matrix": [9, 4], "x": 13.25, "y": 3},
+                {"label": "'", "matrix": [9, 5], "x": 14.25, "y": 3},
+                {"label": "Enter", "matrix": [9, 7], "x": 15.25, "y": 3, "w": 2.25},
+                {"label": "PgDn", "matrix": [9, 8], "x": 18, "y": 3},
+                {"label": "M4", "matrix": [4, 0], "x": 0, "y": 4},
+                {"label": "Shift", "matrix": [4, 1], "x": 1.5, "y": 4, "w": 2.25},
+                {"label": "Z", "matrix": [4, 3], "x": 3.75, "y": 4},
+                {"label": "X", "matrix": [4, 4], "x": 4.75, "y": 4},
+                {"label": "C", "matrix": [4, 5], "x": 5.75, "y": 4},
+                {"label": "V", "matrix": [4, 6], "x": 6.75, "y": 4},
+                {"label": "B", "matrix": [4, 7], "x": 7.75, "y": 4},
+                {"label": "N", "matrix": [10, 0], "x": 9.75, "y": 4},
+                {"label": "M", "matrix": [10, 1], "x": 10.75, "y": 4},
+                {"label": ",", "matrix": [10, 2], "x": 11.75, "y": 4},
+                {"label": ".", "matrix": [10, 3], "x": 12.75, "y": 4},
+                {"label": "/", "matrix": [10, 4], "x": 13.75, "y": 4},
+                {"label": "Shift", "matrix": [10, 6], "x": 14.75, "y": 4, "w": 1.75},
+                {"label": "Up", "matrix": [10, 7], "x": 16.75, "y": 4},
+                {"label": "End", "matrix": [10, 8], "x": 18, "y": 4},
+                {"label": "M5", "matrix": [5, 0], "x": 0, "y": 5},
+                {"label": "Ctrl", "matrix": [5, 1], "x": 1.5, "y": 5, "w": 1.25},
+                {"label": "Gui", "matrix": [5, 2], "x": 2.75, "y": 5, "w": 1.25},
+                {"label": "Alt", "matrix": [5, 3], "x": 4, "y": 5, "w": 1.25},
+                {"label": "Space", "matrix": [5, 4], "x": 5.25, "y": 5, "w": 2.25},
+                {"label": "FN", "matrix": [5, 7], "x": 7.5, "y": 5, "w": 1.25},
+                {"label": "Space", "matrix": [11, 1], "x": 9.75, "y": 5, "w": 2.75},
+                {"label": "Alt", "matrix": [11, 3], "x": 12.5, "y": 5},
+                {"label": "Gui", "matrix": [11, 4], "x": 13.5, "y": 5},
+                {"label": "Ctrl", "matrix": [11, 5], "x": 14.5, "y": 5},
+                {"label": "Left", "matrix": [11, 6], "x": 15.75, "y": 5},
+                {"label": "Down", "matrix": [11, 7], "x": 16.75, "y": 5},
+                {"label": "Rght", "matrix": [11, 8], "x": 17.75, "y": 5}
+            ]
+        },
+        "LAYOUT_iso": {
+            "layout": [
+                {"label": "LENC", "matrix": [0, 0], "x": 0, "y": 0},
+                {"label": "ESC", "matrix": [0, 1], "x": 1.5, "y": 0},
+                {"label": "F1", "matrix": [0, 2], "x": 2.75, "y": 0},
+                {"label": "F2", "matrix": [0, 3], "x": 3.75, "y": 0},
+                {"label": "F3", "matrix": [0, 4], "x": 4.75, "y": 0},
+                {"label": "F4", "matrix": [0, 5], "x": 5.75, "y": 0},
+                {"label": "F5", "matrix": [0, 6], "x": 7, "y": 0},
+                {"label": "F6", "matrix": [0, 7], "x": 8, "y": 0},
+                {"label": "F7", "matrix": [6, 0], "x": 10, "y": 0},
+                {"label": "F8", "matrix": [6, 1], "x": 11, "y": 0},
+                {"label": "F9", "matrix": [6, 2], "x": 12.25, "y": 0},
+                {"label": "F10", "matrix": [6, 3], "x": 13.25, "y": 0},
+                {"label": "F11", "matrix": [6, 4], "x": 14.25, "y": 0},
+                {"label": "F12", "matrix": [6, 5], "x": 15.25, "y": 0},
+                {"label": "F13", "matrix": [6, 6], "x": 16.5, "y": 0},
+                {"label": "RENC", "matrix": [6, 8], "x": 18, "y": 0},
+                {"label": "M1", "matrix": [1, 0], "x": 0, "y": 1},
+                {"label": "GRAV", "matrix": [1, 1], "x": 1.5, "y": 1},
+                {"label": "1", "matrix": [1, 2], "x": 2.5, "y": 1},
+                {"label": "2", "matrix": [1, 3], "x": 3.5, "y": 1},
+                {"label": "3", "matrix": [1, 4], "x": 4.5, "y": 1},
+                {"label": "4", "matrix": [1, 5], "x": 5.5, "y": 1},
+                {"label": "5", "matrix": [1, 6], "x": 6.5, "y": 1},
+                {"label": "6", "matrix": [1, 7], "x": 7.5, "y": 1},
+                {"label": "7", "matrix": [7, 0], "x": 9.5, "y": 1},
+                {"label": "8", "matrix": [7, 1], "x": 10.5, "y": 1},
+                {"label": "9", "matrix": [7, 2], "x": 11.5, "y": 1},
+                {"label": "0", "matrix": [7, 3], "x": 12.5, "y": 1},
+                {"label": "-", "matrix": [7, 4], "x": 13.5, "y": 1},
+                {"label": "=", "matrix": [7, 5], "x": 14.5, "y": 1},
+                {"label": "Back", "matrix": [7, 6], "x": 15.5, "y": 1, "w": 2},
+                {"label": "Home", "matrix": [7, 8], "x": 18, "y": 1},
+                {"label": "M2", "matrix": [2, 0], "x": 0, "y": 2},
+                {"label": "Tab", "matrix": [2, 1], "x": 1.5, "y": 2, "w": 1.5},
+                {"label": "Q", "matrix": [2, 3], "x": 3, "y": 2},
+                {"label": "W", "matrix": [2, 4], "x": 4, "y": 2},
+                {"label": "E", "matrix": [2, 5], "x": 5, "y": 2},
+                {"label": "R", "matrix": [2, 6], "x": 6, "y": 2},
+                {"label": "T", "matrix": [2, 7], "x": 7, "y": 2},
+                {"label": "Y", "matrix": [8, 0], "x": 9, "y": 2},
+                {"label": "U", "matrix": [8, 1], "x": 10, "y": 2},
+                {"label": "I", "matrix": [8, 2], "x": 11, "y": 2},
+                {"label": "O", "matrix": [8, 3], "x": 12, "y": 2},
+                {"label": "P", "matrix": [8, 4], "x": 13, "y": 2},
+                {"label": "[", "matrix": [8, 5], "x": 14, "y": 2},
+                {"label": "]", "matrix": [8, 6], "x": 15, "y": 2},
+                {"label": "PgUp", "matrix": [8, 8], "x": 18, "y": 2},
+                {"label": "M3", "matrix": [3, 0], "x": 0, "y": 3},
+                {"label": "Caps", "matrix": [3, 1], "x": 1.5, "y": 3, "w": 1.75},
+                {"label": "A", "matrix": [3, 3], "x": 3.25, "y": 3},
+                {"label": "S", "matrix": [3, 4], "x": 4.25, "y": 3},
+                {"label": "D", "matrix": [3, 5], "x": 5.25, "y": 3},
+                {"label": "F", "matrix": [3, 6], "x": 6.25, "y": 3},
+                {"label": "G", "matrix": [3, 7], "x": 7.25, "y": 3},
+                {"label": "H", "matrix": [9, 0], "x": 9.25, "y": 3},
+                {"label": "J", "matrix": [9, 1], "x": 10.25, "y": 3},
+                {"label": "K", "matrix": [9, 2], "x": 11.25, "y": 3},
+                {"label": "L", "matrix": [9, 3], "x": 12.25, "y": 3},
+                {"label": ";", "matrix": [9, 4], "x": 13.25, "y": 3},
+                {"label": "'", "matrix": [9, 5], "x": 14.25, "y": 3},
+                {"label": "NUHS", "matrix": [9, 6], "x": 15.25, "y": 3},
+                {"label": "Enter", "matrix": [9, 7], "x": 16.25, "y": 2, "w": 1.25, "h": 2},
+                {"label": "PgDn", "matrix": [9, 8], "x": 18, "y": 3},
+                {"label": "M4", "matrix": [4, 0], "x": 0, "y": 4},
+                {"label": "Shift", "matrix": [4, 1], "x": 1.5, "y": 4, "w": 1.25},
+                {"label": "NUBS", "matrix": [4, 2], "x": 2.75, "y": 4},
+                {"label": "Z", "matrix": [4, 3], "x": 3.75, "y": 4},
+                {"label": "X", "matrix": [4, 4], "x": 4.75, "y": 4},
+                {"label": "C", "matrix": [4, 5], "x": 5.75, "y": 4},
+                {"label": "V", "matrix": [4, 6], "x": 6.75, "y": 4},
+                {"label": "B", "matrix": [4, 7], "x": 7.75, "y": 4},
+                {"label": "N", "matrix": [10, 0], "x": 9.75, "y": 4},
+                {"label": "M", "matrix": [10, 1], "x": 10.75, "y": 4},
+                {"label": ",", "matrix": [10, 2], "x": 11.75, "y": 4},
+                {"label": ".", "matrix": [10, 3], "x": 12.75, "y": 4},
+                {"label": "/", "matrix": [10, 4], "x": 13.75, "y": 4},
+                {"label": "Shift", "matrix": [10, 6], "x": 14.75, "y": 4, "w": 1.75},
+                {"label": "Up", "matrix": [10, 7], "x": 16.75, "y": 4},
+                {"label": "End", "matrix": [10, 8], "x": 18, "y": 4},
+                {"label": "M5", "matrix": [5, 0], "x": 0, "y": 5},
+                {"label": "Ctrl", "matrix": [5, 1], "x": 1.5, "y": 5, "w": 1.25},
+                {"label": "Gui", "matrix": [5, 2], "x": 2.75, "y": 5, "w": 1.25},
+                {"label": "Alt", "matrix": [5, 3], "x": 4, "y": 5, "w": 1.25},
+                {"label": "Space", "matrix": [5, 4], "x": 5.25, "y": 5, "w": 2.25},
+                {"label": "FN", "matrix": [5, 7], "x": 7.5, "y": 5, "w": 1.25},
+                {"label": "Space", "matrix": [11, 1], "x": 9.75, "y": 5, "w": 2.75},
+                {"label": "Alt", "matrix": [11, 3], "x": 12.5, "y": 5},
+                {"label": "Gui", "matrix": [11, 4], "x": 13.5, "y": 5},
+                {"label": "Ctrl", "matrix": [11, 5], "x": 14.5, "y": 5},
+                {"label": "Left", "matrix": [11, 6], "x": 15.75, "y": 5},
+                {"label": "Down", "matrix": [11, 7], "x": 16.75, "y": 5},
+                {"label": "Rght", "matrix": [11, 8], "x": 17.75, "y": 5}
+            ]
+        }
+    }
+}
diff --git a/keyboards/haverworks/theseus75/keymaps/ansi/keymap.c b/keyboards/haverworks/theseus75/keymaps/ansi/keymap.c
new file mode 100644
index 00000000000..25494f7e47d
--- /dev/null
+++ b/keyboards/haverworks/theseus75/keymaps/ansi/keymap.c
@@ -0,0 +1,31 @@
+// Copyright 2023 Moritz Plattner (@ebastler), Alex Havermale (@haversnail)
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+#include QMK_KEYBOARD_H
+
+const uint16_t PROGMEM keymaps[][MATRIX_ROWS][MATRIX_COLS] = {
+
+    [0] = LAYOUT_ansi(
+        RM_TOGG, KC_ESC,  KC_F1,   KC_F2,   KC_F3,   KC_F4,   KC_F5,   KC_F6,   KC_F7,   KC_F8,   KC_F9,   KC_F10,  KC_F11,  KC_F12,  KC_PSCR,          KC_MUTE,
+        KC_F13,  KC_GRV,  KC_1,    KC_2,    KC_3,    KC_4,    KC_5,    KC_6,    KC_7,    KC_8,    KC_9,    KC_0,    KC_MINS, KC_EQL,  KC_BSPC,          KC_HOME,
+        KC_F14,  KC_TAB,  KC_Q,    KC_W,    KC_E,    KC_R,    KC_T,    KC_Y,    KC_U,    KC_I,    KC_O,    KC_P,    KC_LBRC, KC_RBRC, KC_BSLS,          KC_PGUP,
+        KC_F15,  KC_CAPS, KC_A,    KC_S,    KC_D,    KC_F,    KC_G,    KC_H,    KC_J,    KC_K,    KC_L,    KC_SCLN, KC_QUOT,          KC_ENT,           KC_PGDN,
+        KC_F16,  KC_LSFT,          KC_Z,    KC_X,    KC_C,    KC_V,    KC_B,    KC_N,    KC_M,    KC_COMM, KC_DOT,  KC_SLSH,          KC_RSFT, KC_UP,   KC_END,
+        KC_F17,  KC_LCTL, KC_LGUI, KC_LALT,                   KC_SPC,  MO(1),   KC_SPC,                    KC_RALT, KC_RGUI, KC_RCTL, KC_LEFT, KC_DOWN, KC_RGHT
+    ),
+    [1] = LAYOUT_ansi(
+        KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS,          KC_MPLY,
+        KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_DEL,           KC_TRNS,
+        KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS,          KC_TRNS,
+        KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS,          KC_TRNS,          KC_TRNS,
+        KC_TRNS, KC_TRNS,          KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS,          KC_TRNS, KC_TRNS, KC_TRNS,
+        KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS,                   KC_TRNS, KC_TRNS, KC_TRNS,                   KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS
+    )
+};
+
+#ifdef ENCODER_MAP_ENABLE
+const uint16_t PROGMEM encoder_map[][NUM_ENCODERS][NUM_DIRECTIONS] = {
+    [0] = { ENCODER_CCW_CW(RM_VALD, RM_VALU), ENCODER_CCW_CW(KC_VOLD, KC_VOLU) },
+    [1] = { ENCODER_CCW_CW(RM_PREV, RM_NEXT), ENCODER_CCW_CW(KC_MPRV, KC_MNXT) },
+};
+#endif
diff --git a/keyboards/haverworks/theseus75/keymaps/ansi/rules.mk b/keyboards/haverworks/theseus75/keymaps/ansi/rules.mk
new file mode 100644
index 00000000000..ee325681483
--- /dev/null
+++ b/keyboards/haverworks/theseus75/keymaps/ansi/rules.mk
@@ -0,0 +1 @@
+ENCODER_MAP_ENABLE = yes
diff --git a/keyboards/haverworks/theseus75/keymaps/default/keymap.c b/keyboards/haverworks/theseus75/keymaps/default/keymap.c
new file mode 100644
index 00000000000..5e56d121ebe
--- /dev/null
+++ b/keyboards/haverworks/theseus75/keymaps/default/keymap.c
@@ -0,0 +1,31 @@
+// Copyright 2023 Moritz Plattner (@ebastler), Alex Havermale (@haversnail)
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+#include QMK_KEYBOARD_H
+
+const uint16_t PROGMEM keymaps[][MATRIX_ROWS][MATRIX_COLS] = {
+
+    [0] = LAYOUT_all(
+        RM_TOGG, KC_ESC,  KC_F1,   KC_F2,   KC_F3,   KC_F4,   KC_F5,   KC_F6,   KC_F7,   KC_F8,   KC_F9,   KC_F10,  KC_F11,  KC_F12,  KC_PSCR,          KC_MUTE,
+        KC_F13,  KC_GRV,  KC_1,    KC_2,    KC_3,    KC_4,    KC_5,    KC_6,    KC_7,    KC_8,    KC_9,    KC_0,    KC_MINS, KC_EQL,  KC_BSPC, KC_DEL,  KC_HOME,
+        KC_F14,  KC_TAB,  KC_Q,    KC_W,    KC_E,    KC_R,    KC_T,    KC_Y,    KC_U,    KC_I,    KC_O,    KC_P,    KC_LBRC, KC_RBRC, KC_BSLS,          KC_PGUP,
+        KC_F15,  KC_CAPS, KC_A,    KC_S,    KC_D,    KC_F,    KC_G,    KC_H,    KC_J,    KC_K,    KC_L,    KC_SCLN, KC_QUOT, KC_NUHS, KC_ENT,           KC_PGDN,
+        KC_F16,  KC_LSFT, KC_NUBS, KC_Z,    KC_X,    KC_C,    KC_V,    KC_B,    KC_N,    KC_M,    KC_COMM, KC_DOT,  KC_SLSH,          KC_RSFT, KC_UP,   KC_END,
+        KC_F17,  KC_LCTL, KC_LGUI, KC_LALT,                   KC_SPC,  MO(1),   KC_SPC,                    KC_RALT, KC_RGUI, KC_RCTL, KC_LEFT, KC_DOWN, KC_RGHT
+    ),
+    [1] = LAYOUT_all(
+        KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS,          KC_MPLY,
+        KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS,
+        KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS,          KC_TRNS,
+        KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS,          KC_TRNS,
+        KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS,          KC_TRNS, KC_TRNS, KC_TRNS,
+        KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS,                   KC_TRNS, KC_TRNS, KC_TRNS,                   KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS
+    )
+};
+
+#ifdef ENCODER_MAP_ENABLE
+const uint16_t PROGMEM encoder_map[][NUM_ENCODERS][NUM_DIRECTIONS] = {
+    [0] = { ENCODER_CCW_CW(RM_VALD, RM_VALU), ENCODER_CCW_CW(KC_VOLD, KC_VOLU) },
+    [1] = { ENCODER_CCW_CW(RM_PREV, RM_NEXT), ENCODER_CCW_CW(KC_MPRV, KC_MNXT) },
+};
+#endif
diff --git a/keyboards/haverworks/theseus75/keymaps/default/rules.mk b/keyboards/haverworks/theseus75/keymaps/default/rules.mk
new file mode 100644
index 00000000000..ee325681483
--- /dev/null
+++ b/keyboards/haverworks/theseus75/keymaps/default/rules.mk
@@ -0,0 +1 @@
+ENCODER_MAP_ENABLE = yes
diff --git a/keyboards/haverworks/theseus75/keymaps/iso/keymap.c b/keyboards/haverworks/theseus75/keymaps/iso/keymap.c
new file mode 100644
index 00000000000..d7487010ee7
--- /dev/null
+++ b/keyboards/haverworks/theseus75/keymaps/iso/keymap.c
@@ -0,0 +1,31 @@
+// Copyright 2023 Moritz Plattner (@ebastler), Alex Havermale (@haversnail)
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+#include QMK_KEYBOARD_H
+
+const uint16_t PROGMEM keymaps[][MATRIX_ROWS][MATRIX_COLS] = {
+
+    [0] = LAYOUT_iso(
+        RM_TOGG, KC_ESC,  KC_F1,   KC_F2,   KC_F3,   KC_F4,   KC_F5,   KC_F6,   KC_F7,   KC_F8,   KC_F9,   KC_F10,  KC_F11,  KC_F12,  KC_PSCR,          KC_MUTE,
+        KC_F13,  KC_GRV,  KC_1,    KC_2,    KC_3,    KC_4,    KC_5,    KC_6,    KC_7,    KC_8,    KC_9,    KC_0,    KC_MINS, KC_EQL,  KC_BSPC,          KC_HOME,
+        KC_F14,  KC_TAB,  KC_Q,    KC_W,    KC_E,    KC_R,    KC_T,    KC_Y,    KC_U,    KC_I,    KC_O,    KC_P,    KC_LBRC, KC_RBRC,                   KC_PGUP,
+        KC_F15,  KC_CAPS, KC_A,    KC_S,    KC_D,    KC_F,    KC_G,    KC_H,    KC_J,    KC_K,    KC_L,    KC_SCLN, KC_QUOT, KC_NUHS, KC_ENT,           KC_PGDN,
+        KC_F16,  KC_LSFT, KC_NUBS, KC_Z,    KC_X,    KC_C,    KC_V,    KC_B,    KC_N,    KC_M,    KC_COMM, KC_DOT,  KC_SLSH,          KC_RSFT, KC_UP,   KC_END,
+        KC_F17,  KC_LCTL, KC_LGUI, KC_LALT,                   KC_SPC,  MO(1),   KC_SPC,                    KC_RALT, KC_RGUI, KC_RCTL, KC_LEFT, KC_DOWN, KC_RGHT
+    ),
+    [1] = LAYOUT_iso(
+        KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS,          KC_MPLY,
+        KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_DEL,           KC_TRNS,
+        KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS,                   KC_TRNS,
+        KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS,          KC_TRNS,
+        KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS,          KC_TRNS, KC_TRNS, KC_TRNS,
+        KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS,                   KC_TRNS, KC_TRNS, KC_TRNS,                   KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS
+    )
+};
+
+#ifdef ENCODER_MAP_ENABLE
+const uint16_t PROGMEM encoder_map[][NUM_ENCODERS][NUM_DIRECTIONS] = {
+    [0] = { ENCODER_CCW_CW(RM_VALD, RM_VALU), ENCODER_CCW_CW(KC_VOLD, KC_VOLU) },
+    [1] = { ENCODER_CCW_CW(RM_PREV, RM_NEXT), ENCODER_CCW_CW(KC_MPRV, KC_MNXT) },
+};
+#endif
diff --git a/keyboards/haverworks/theseus75/keymaps/iso/rules.mk b/keyboards/haverworks/theseus75/keymaps/iso/rules.mk
new file mode 100644
index 00000000000..ee325681483
--- /dev/null
+++ b/keyboards/haverworks/theseus75/keymaps/iso/rules.mk
@@ -0,0 +1 @@
+ENCODER_MAP_ENABLE = yes
diff --git a/keyboards/haverworks/theseus75/mcuconf.h b/keyboards/haverworks/theseus75/mcuconf.h
new file mode 100644
index 00000000000..a3dbdb4ba26
--- /dev/null
+++ b/keyboards/haverworks/theseus75/mcuconf.h
@@ -0,0 +1,14 @@
+// Copyright 2023 Moritz Plattner (@ebastler)
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+#pragma once
+
+#include_next <mcuconf.h>
+
+/* enable USART3, used for split comms */
+#undef STM32_SERIAL_USE_USART3
+#define STM32_SERIAL_USE_USART3 TRUE
+
+/* enable TIM3, used for Underglow PWM driver */
+#undef STM32_PWM_USE_TIM3
+#define STM32_PWM_USE_TIM3 TRUE
diff --git a/keyboards/haverworks/theseus75/readme.md b/keyboards/haverworks/theseus75/readme.md
new file mode 100644
index 00000000000..7119f61a643
--- /dev/null
+++ b/keyboards/haverworks/theseus75/readme.md
@@ -0,0 +1,31 @@
+# Haverworks Theseus75
+
+![Theseus75 v1 PCB](https://imgur.com/N81LsCO.png)
+
+The Theseus75 is a 75% row-staggered split keyboard with a macro column and rotary encoders on both sides. Each half features a dual-role USB-C port and integrated USB hub, allowing the unused port to act as a USB-C 2.0 High-Speed host for connecting a numpad, mouse, flash drive, security key, mobile phone, or similar device.
+
+> [!NOTE]
+> Up to 5V at 1.5A can be supplied, depending on negotiations with the host.
+
+* Keyboard Maintainers: [Moritz Plattner](https://github.com/ebastler), [Alex Havermale](https://github.com/haversnail)
+* Hardware Supported: Haverworks Theseus75 v1 PCBs (hot-swap and solder)
+* Hardware Availability: [Group buy](https://haver.works/theseus75)
+
+Make example for this keyboard (after setting up your build environment):
+
+    make haverworks/theseus75:default
+
+Flashing example for this keyboard:
+
+    make haverworks/theseus75:default:flash
+
+See the [build environment setup](https://docs.qmk.fm/#/getting_started_build_tools) and the [make instructions](https://docs.qmk.fm/#/getting_started_make_guide) for more information. Brand new to QMK? Start with our [Complete Newbs Guide](https://docs.qmk.fm/#/newbs).
+
+## Bootloader
+
+Enter the bootloader in two ways:
+
+* **Physical reset button**: Hold the <kbd>Reset</kbd>/<kbd>Flash</kbd> button on the back of the PCB for approximately one second (instructions are also included on the PCB)
+* **Bootmagic reset**:
+    * **Left half**: Hold down the first key to the right of the encoder (<kbd>Esc</kbd> by default) and plug in the keyboard
+    * **Right half**: Hold down the first key to the left of the encoder (<kbd>Print Screen</kbd> by default) and plug in the keyboard
diff --git a/keyboards/haverworks/theseus75/theseus75.c b/keyboards/haverworks/theseus75/theseus75.c
new file mode 100644
index 00000000000..45ead4811d1
--- /dev/null
+++ b/keyboards/haverworks/theseus75/theseus75.c
@@ -0,0 +1,214 @@
+// Copyright 2023 Moritz Plattner (@ebastler), Alex Havermale (@haversnail)
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+#include "quantum.h"
+#include "transactions.h"
+#include <stdio.h>
+#include "print.h"
+#include "split_util.h"
+#include "usbpd.h"
+
+typedef struct _kb_state_t {
+    usbpd_allowance_t allowance;
+} kb_state_t;
+
+kb_state_t kb_state;
+
+const char* usbpd_str(usbpd_allowance_t allowance) {
+    switch (allowance) {
+        case USBPD_500MA:
+            return "500mA";
+        case USBPD_1500MA:
+            return "1500mA";
+        case USBPD_3000MA:
+            return "3000mA";
+        default:
+            dprintf("Encountered unknown allowance enum value: %d\n", allowance);
+            return "UNKNOWN";
+    }
+}
+
+void kb_state_slave_handler(uint8_t m2s_size, const void* m2s_buffer, uint8_t s2m_size, void* s2m_buffer) {
+    if (m2s_size == sizeof(kb_state_t)) {
+        memcpy(&kb_state, m2s_buffer, sizeof(kb_state_t));
+    } else {
+        dprintf("Unexpected response in slave handler\n"); // TODO: add split debug logging
+    }
+}
+
+void keyboard_pre_init_kb(void) {
+    // Disable the PD peripheral in pre-init because its pins are being used in the matrix:
+    PWR->CR3 |= PWR_CR3_UCPD_DBDIS;
+    // Call the corresponding _user() function (see https://docs.qmk.fm/#/custom_quantum_functions)
+    keyboard_pre_init_user();
+}
+
+void keyboard_post_init_kb(void) {
+    // Register keyboard state transaction:
+    transaction_register_rpc(RPC_ID_KB_STATE, kb_state_slave_handler);
+
+    // Set default state values:
+    kb_state.allowance = USBPD_500MA;
+
+    // If the keyboard is master,
+    if (is_keyboard_master()) {
+        // Turn on power to the split half and to underglow LEDs:
+        gpio_set_pin_output(PSW_PIN);
+        gpio_write_pin_high(PSW_PIN);
+
+        // Enable inputs used for current negotiation:
+        gpio_set_pin_input_high(USBPD_1_PIN);
+        gpio_set_pin_input_high(USBPD_2_PIN);
+
+        // Not needed in this mode (always high-Z with pull-up on PCB if port controller is sink)
+        gpio_set_pin_input_high(ID_PIN);
+    } else {
+        // Prepare output to enable power for USB output after negotiation:
+        gpio_set_pin_output(PSW_PIN);
+
+        // Switch the USB MUXes between hub and ports:
+        gpio_set_pin_output(USBSW_PIN);
+        gpio_write_pin_high(USBSW_PIN);
+
+        // Enable outputs used for current negotiation and default to 500mA:
+        gpio_set_pin_output(USBPD_1_PIN);
+        gpio_write_pin_high(USBPD_1_PIN);
+        gpio_set_pin_output(USBPD_2_PIN);
+        gpio_write_pin_high(USBPD_2_PIN);
+
+        // Use ID pin to check if client is detected (if low: USB source port powered):
+        gpio_set_pin_input_high(ID_PIN);
+
+        // Indicate that the hub is either self-powered or bus-powered based on whether the bus-power mode flag is enabled
+        // (configurable for users who would rather always have their device connect, regardless of whether they meet the specs):
+        gpio_set_pin_output(BUS_B_PIN);
+        if (DISABLE_BUS_POWER_MODE == TRUE) {
+            gpio_write_pin_high(BUS_B_PIN);
+        } else {
+            gpio_write_pin_low(BUS_B_PIN);
+        }
+    }
+    // Call the corresponding _user() function (see https://docs.qmk.fm/#/custom_quantum_functions)
+    keyboard_post_init_user();
+}
+
+void housekeeping_task_kb(void) {
+    // Update any shared kb state to send to slave:
+    static uint32_t last_usbpd_allowance_check_time = 0;
+    if (timer_elapsed32(last_usbpd_allowance_check_time) > USBPD_ALLOWANCE_CHECK_INTERVAL) {
+        // On master side: check USBPD_1_PIN and USBPD_2_PIN to determine current negotiated with host
+        // (Can't use the usbpd_get_allowance() function, as this uses this uses the native CC PD interface
+        // of the G series MCU, while we're using dedicated port controllers instead):
+        if (is_keyboard_master()) {
+            usbpd_allowance_t allowance;
+
+            if (gpio_read_pin(USBPD_1_PIN)) {
+                allowance = USBPD_500MA;
+            } else if (gpio_read_pin(USBPD_2_PIN)) {
+                allowance = USBPD_1500MA;
+            } else {
+                allowance = USBPD_3000MA;
+            }
+
+            if (kb_state.allowance != allowance) {
+                printf("Host negotiated current: %s -> %s\n", usbpd_str(kb_state.allowance), usbpd_str(allowance));
+                kb_state.allowance = allowance;
+            }
+        } else {
+            // On peripheral side - If ID_PIN is low: USB client negotiated 5V successfully -> enable power routing
+            // Check if PSW_PIN is not already high to avoid wasting time
+            if (!gpio_read_pin(ID_PIN) && !gpio_read_pin(PSW_PIN)) {
+                gpio_write_pin_high(PSW_PIN);
+                dprintf("USB downstream device connected\n"); // TODO: add split debug logging
+            } else if (gpio_read_pin(ID_PIN) && gpio_read_pin(PSW_PIN)) {
+                gpio_write_pin_low(PSW_PIN);
+                dprintf("USB downstream device disconnected\n"); // TODO: add split debug logging
+            }
+        };
+        last_usbpd_allowance_check_time = timer_read32();
+    };
+
+    // Sync state from master to slave:
+    if (is_keyboard_master() && is_transport_connected()) {
+        bool              needs_sync = false;
+        static uint32_t   last_kb_state_sync_time;
+        static kb_state_t last_kb_state;
+
+        // Check if the state values are different:
+        if (memcmp(&kb_state, &last_kb_state, sizeof(kb_state_t))) {
+            needs_sync = true;
+            memcpy(&last_kb_state, &kb_state, sizeof(kb_state_t));
+        }
+
+        // Sync state every so often regardless:
+        if (timer_elapsed32(last_kb_state_sync_time) > KB_STATE_SYNC_INTERVAL) {
+            needs_sync = true;
+        }
+
+        if (needs_sync) {
+            bool did_sync = transaction_rpc_send(RPC_ID_KB_STATE, sizeof(kb_state_t), &kb_state);
+            if (did_sync) {
+                dprintf("Synced to slave\n");
+                last_kb_state_sync_time = timer_read32();
+            } else {
+                dprintf("Failed to sync state\n");
+            }
+        }
+    }
+
+    // Update the USBPD output pins on slave half whenever allowance has changed:
+    if (!is_keyboard_master()) {
+        static usbpd_allowance_t last_allowance;
+
+        if (last_allowance != kb_state.allowance) {
+            last_allowance = kb_state.allowance;
+
+            printf("Setting USB-PD output to %s (%s-powered)\n", usbpd_str(kb_state.allowance), kb_state.allowance == USBPD_500MA ? "bus" : "self"); // TODO: add split debug logging
+
+            switch (kb_state.allowance) {
+                default:
+                case USBPD_500MA:
+                    // Set USBPD output to 500 mA:
+                    gpio_write_pin_high(USBPD_1_PIN);
+                    gpio_write_pin_high(USBPD_2_PIN);
+                    if (DISABLE_BUS_POWER_MODE == TRUE) {
+                        // Indicate hub is self-powered and devices can try to connect or fast charge:
+                        gpio_write_pin_high(BUS_B_PIN);
+                    } else {
+                        // Indicate hub is bus-powered and devices should not try to connect or fast charge:
+                        gpio_write_pin_low(BUS_B_PIN);
+                    }
+                    break;
+                case USBPD_1500MA:
+                    // Set USBPD output to 500 mA:
+                    gpio_write_pin_high(USBPD_1_PIN);
+                    gpio_write_pin_high(USBPD_2_PIN);
+                    // Indicate hub is self-powered and devices can try to connect or fast charge:
+                    gpio_write_pin_high(BUS_B_PIN);
+                    break;
+                case USBPD_3000MA:
+                    // Set USBPD output to 1500 mA:
+                    gpio_write_pin_low(USBPD_1_PIN);
+                    gpio_write_pin_high(USBPD_2_PIN);
+                    // Indicate hub is self-powered and devices can try to connect or fast charge:
+                    gpio_write_pin_high(BUS_B_PIN);
+                    break;
+            }
+        }
+    }
+}
+
+#ifdef RGB_MATRIX_ENABLE
+bool rgb_matrix_indicators_kb(void) {
+    if (!rgb_matrix_indicators_user()) {
+        return false;
+    }
+
+    if (host_keyboard_led_state().caps_lock) {
+        rgb_matrix_set_color(CAPS_LOCK_LED_INDEX, INDICATOR_MAX_BRIGHTNESS, INDICATOR_MAX_BRIGHTNESS, INDICATOR_MAX_BRIGHTNESS);
+    } else {
+        rgb_matrix_set_color(CAPS_LOCK_LED_INDEX, 0, 0, 0);
+    }
+    return true;
+}
+#endif