diff --git a/keyboards/ploopyco/trackball_thumb/config.h b/keyboards/ploopyco/trackball_thumb/config.h
new file mode 100644
index 00000000000..97553a79595
--- /dev/null
+++ b/keyboards/ploopyco/trackball_thumb/config.h
@@ -0,0 +1,38 @@
+/* Copyright 2021 Colin Lam (Ploopy Corporation)
+ * Copyright 2020 Christopher Courtney, aka Drashna Jael're  (@drashna) <drashna@live.com>
+ * Copyright 2019 Sunjun Kim
+ *
+ * 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 2 of the License, or
+ * (at your option) 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.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#pragma once
+
+#include "config_common.h"
+
+/* define if matrix has ghost (lacks anti-ghosting diodes) */
+//#define MATRIX_HAS_GHOST
+
+/* disable action features */
+//#define NO_ACTION_LAYER
+//#define NO_ACTION_TAPPING
+//#define NO_ACTION_ONESHOT
+
+// #define ROTATIONAL_TRANSFORM_ANGLE 0
+#define POINTING_DEVICE_INVERT_Y
+
+// If board has a debug LED, you can enable it by defining this
+// #define DEBUG_LED_PIN F7
+
+/* PMW3360 Settings */
+#define POINTING_DEVICE_CS_PIN B0
diff --git a/keyboards/ploopyco/trackball_thumb/info.json b/keyboards/ploopyco/trackball_thumb/info.json
new file mode 100644
index 00000000000..b76e2bd7fe2
--- /dev/null
+++ b/keyboards/ploopyco/trackball_thumb/info.json
@@ -0,0 +1,36 @@
+{
+    "keyboard_name": "PloopyCo Thumb Trackball",
+    "url": "www.ploopy.co",
+    "maintainer": "ploopyco",
+    "manufacturer": "Ploopy Corporation",
+    "processor": "atmega32u4",
+    "bootloader": "atmel-dfu",
+    "usb": {
+        "vid": "0x5043",
+        "pid": "0x5C46",
+        "max_power": 100
+    },
+    "features": {
+        "bootmagic": true,
+        "command": false,
+        "console": false,
+        "extrakey": true,
+        "mousekey": true,
+        "nkro": true,
+        "pointing_device": true,
+        "encoder": false
+    },
+    "debounce": 5,
+    "layouts": {
+        "LAYOUT": {
+            "layout": [
+                {"matrix":[0,0], "x":0, "y":0, "h": 1},
+                {"matrix":[0,2], "x":1, "y":0, "h":2},
+                {"matrix":[0,3],"x":2.5, "y":0.25, "h":1.5},
+                {"matrix":[0,4],"x":4, "y":0, "h":2},
+                {"matrix":[0,5],"x":5, "y":0.5, "h":1},
+                {"matrix":[0,1],"x":0, "y":1, "h":1}
+            ]
+        }
+    }
+}
diff --git a/keyboards/ploopyco/trackball_thumb/keymaps/default/keymap.c b/keyboards/ploopyco/trackball_thumb/keymaps/default/keymap.c
new file mode 100644
index 00000000000..897a5761c7b
--- /dev/null
+++ b/keyboards/ploopyco/trackball_thumb/keymaps/default/keymap.c
@@ -0,0 +1,27 @@
+/* Copyright 2021 Colin Lam (Ploopy Corporation)
+ * Copyright 2020 Christopher Courtney, aka Drashna Jael're  (@drashna) <drashna@live.com>
+ * Copyright 2019 Sunjun Kim
+ *
+ * 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 2 of the License, or
+ * (at your option) 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.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+#include QMK_KEYBOARD_H
+
+// safe range starts at `PLOOPY_SAFE_RANGE` instead.
+
+const uint16_t PROGMEM keymaps[][MATRIX_ROWS][MATRIX_COLS] = {
+    [0] = LAYOUT( /* Base */
+        KC_BTN4, KC_BTN1, KC_BTN3, KC_BTN2, KC_BTN5,
+        DPI_CONFIG
+    ),
+};
diff --git a/keyboards/ploopyco/trackball_thumb/keymaps/default/readme.md b/keyboards/ploopyco/trackball_thumb/keymaps/default/readme.md
new file mode 100644
index 00000000000..0f21a21ba6f
--- /dev/null
+++ b/keyboards/ploopyco/trackball_thumb/keymaps/default/readme.md
@@ -0,0 +1 @@
+# The default keymap for Ploopyco Thumb Trackball
diff --git a/keyboards/ploopyco/trackball_thumb/keymaps/drag_scroll/keymap.c b/keyboards/ploopyco/trackball_thumb/keymaps/drag_scroll/keymap.c
new file mode 100644
index 00000000000..03202cc8f7a
--- /dev/null
+++ b/keyboards/ploopyco/trackball_thumb/keymaps/drag_scroll/keymap.c
@@ -0,0 +1,30 @@
+/* Copyright 2021 Colin Lam (Ploopy Corporation)
+ * Copyright 2020 Christopher Courtney, aka Drashna Jael're  (@drashna) <drashna@live.com>
+ * Copyright 2019 Sunjun Kim
+ *
+ * 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 2 of the License, or
+ * (at your option) 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.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+#include QMK_KEYBOARD_H
+
+
+const uint16_t PROGMEM keymaps[][MATRIX_ROWS][MATRIX_COLS] = {
+    [0] = LAYOUT( /* Base */
+        KC_BTN4, KC_BTN1, KC_BTN3, KC_BTN2, KC_BTN5,
+        MO(1)
+    ),
+    [1] = LAYOUT(
+        _______, _______, _______, _______, _______,
+        DRAG_SCROLL
+    )
+};
diff --git a/keyboards/ploopyco/trackball_thumb/keymaps/drag_scroll/readme.md b/keyboards/ploopyco/trackball_thumb/keymaps/drag_scroll/readme.md
new file mode 100644
index 00000000000..22119b7ef9b
--- /dev/null
+++ b/keyboards/ploopyco/trackball_thumb/keymaps/drag_scroll/readme.md
@@ -0,0 +1,3 @@
+# The Drag Scroll keymap for Ploopyco Thumb Trackball
+
+This is a sample keymap showing off what you can do with the custom callback drivers. 
diff --git a/keyboards/ploopyco/trackball_thumb/keymaps/via/config.h b/keyboards/ploopyco/trackball_thumb/keymaps/via/config.h
new file mode 100644
index 00000000000..7670e631761
--- /dev/null
+++ b/keyboards/ploopyco/trackball_thumb/keymaps/via/config.h
@@ -0,0 +1,21 @@
+/* Copyright 2021 Colin Lam (Ploopy Corporation)
+ * Copyright 2020 Christopher Courtney, aka Drashna Jael're  (@drashna) <drashna@live.com>
+ * Copyright 2019 Sunjun Kim
+ *
+ * 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 2 of the License, or
+ * (at your option) 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.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#pragma once
+
+#define DYNAMIC_KEYMAP_LAYER_COUNT 8
diff --git a/keyboards/ploopyco/trackball_thumb/keymaps/via/keymap.c b/keyboards/ploopyco/trackball_thumb/keymaps/via/keymap.c
new file mode 100644
index 00000000000..1951535b69f
--- /dev/null
+++ b/keyboards/ploopyco/trackball_thumb/keymaps/via/keymap.c
@@ -0,0 +1,30 @@
+/* Copyright 2021 Colin Lam (Ploopy Corporation)
+ * Copyright 2020 Christopher Courtney, aka Drashna Jael're  (@drashna) <drashna@live.com>
+ * Copyright 2019 Sunjun Kim
+ *
+ * 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 2 of the License, or
+ * (at your option) 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.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+#include QMK_KEYBOARD_H
+
+
+const uint16_t PROGMEM keymaps[][MATRIX_ROWS][MATRIX_COLS] = {
+    [0] = LAYOUT( KC_BTN4, KC_BTN1, KC_BTN3, KC_BTN2, KC_BTN5, DPI_CONFIG ),
+    [1] = LAYOUT( _______, _______, _______, _______, _______, _______ ),
+    [2] = LAYOUT( _______, _______, _______, _______, _______, _______ ),
+    [3] = LAYOUT( _______, _______, _______, _______, _______, _______ ),
+    [4] = LAYOUT( _______, _______, _______, _______, _______, _______ ),
+    [5] = LAYOUT( _______, _______, _______, _______, _______, _______ ),
+    [6] = LAYOUT( _______, _______, _______, _______, _______, _______ ),
+    [7] = LAYOUT( _______, _______, _______, _______, _______, _______ )
+};
diff --git a/keyboards/ploopyco/trackball_thumb/keymaps/via/rules.mk b/keyboards/ploopyco/trackball_thumb/keymaps/via/rules.mk
new file mode 100644
index 00000000000..1e5b99807cb
--- /dev/null
+++ b/keyboards/ploopyco/trackball_thumb/keymaps/via/rules.mk
@@ -0,0 +1 @@
+VIA_ENABLE = yes
diff --git a/keyboards/ploopyco/trackball_thumb/post_rules.mk b/keyboards/ploopyco/trackball_thumb/post_rules.mk
new file mode 100644
index 00000000000..d922afd9cd7
--- /dev/null
+++ b/keyboards/ploopyco/trackball_thumb/post_rules.mk
@@ -0,0 +1,4 @@
+# Force encoder to be disabled
+# But enable the defines for it
+ENCODER_ENABLE := no
+OPT_DEFS += -DENCODER_ENABLE
diff --git a/keyboards/ploopyco/trackball_thumb/readme.md b/keyboards/ploopyco/trackball_thumb/readme.md
new file mode 100644
index 00000000000..83ac740f855
--- /dev/null
+++ b/keyboards/ploopyco/trackball_thumb/readme.md
@@ -0,0 +1,58 @@
+# Ploopyco Thumb Trackball
+
+It's a DIY, QMK Powered Trackball...for thumb ballers!
+
+* Keyboard Maintainer: [PloopyCo](https://github.com/ploopyco), [Drashna Jael're](https://github.com/drashna/), [Germ](https://github.com/germ/)
+* Hardware Supported: ATMega32u4 8MHz(3.3v)
+* Hardware Availability: [Store](https://ploopy.co), [GitHub](https://github.com/ploopyco)
+
+Make example for this keyboard (after setting up your build environment):
+
+    make ploopyco/trackball_thumb/rev1_001:default:flash
+    
+To jump to the bootloader, hold down "Button 4" (button closest to the USB port).
+
+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).
+
+# Customizing your PloopyCo Thumb
+
+While the defaults are designed so that it can be plugged in and used right away, there are a number of things that you may want to change.  Such as adding DPI control, or to use the ball to scroll while holding a button.   To allow for this sort of control, there is a callback for both the scroll wheel and the mouse sensor.
+
+The default behavior for this is:
+
+```c
+report_mouse_t pointing_device_task_kb(report_mouse_t mouse_report) {
+
+    return mouse_report;
+}
+```
+
+This should allow you to more heavily customize the behavior. 
+
+Alternatively, the `process_wheel` and `process_mouse` functions can both be replaced too, to allow for even more functionality.
+
+Additionally, you can change the DPI/CPI or speed of the trackball by calling `pmw_set_cpi` at any time. Additionally, there is a `DPI_CONFIG` keycode that will cycle through an array of options for the DPI.  This is set to 1200, 1600, and 2400, but can be changed.  1600 is also set to the default.
+
+To configure/set your own array, there are two defines to use, `PLOOPY_DPI_OPTIONS` to set the array, and `PLOOPY_DPI_DEFAULT`, which is the `0`-based index into the `PLOOPY_DPI_OPTIONS` array. 
+
+```c
+#define PLOOPY_DPI_OPTIONS { 1200, 1600, 2400 }
+#define PLOOPY_DPI_DEFAULT 1
+```
+The `PLOOPY_DPI_OPTIONS` array sets the values that you want to be able to cycle through, and the order they are in.  The "default" define lets the firmware know which of these options is the default and should be loaded by default. 
+
+When inserted into your keymap, the `DPI_CONFIG` keycode will cycle through the values in the array each time you hit it.  It stores this value in persistent memory, so it will remember your selection the next time the device powers up. 
+
+## Drag Scroll
+
+Drag Scroll is a custom keycode for the Ploopy devices that allow you to hold or tap a button and have the mouse movement translate into scrolling instead. 
+
+Nothing needs to be enabled to use this functionality.  Just add the `DRAG_SCROLL` to your keymap. 
+
+### Drag Scroll Configuration
+
+* `#define PLOOPY_DRAGSCROLL_MOMENTARY` - Makes the key into a momentary key, rather than a toggle.
+* `#define PLOOPY_DRAGSCROLL_MULTIPLIER 0.75` - Sets the DPI multiplier to use when drag scroll is enabled. 
+* `#define PLOOPY_DRAGSCROLL_FIXED` - Normally, when activating Drag Scroll, it uses a fraction of the current DPI. You can define this to use a specific, set DPI rather than a fraction of the current DPI. 
+  * `#define PLOOPY_DRAGSCROLL_DPI 100` - When the fixed DPI option is enabled, this sets the DPI to be used for Drag Scroll.
+* `#define PLOOPY_DRAGSCROLL_INVERT` - This reverses the direction that the scroll is performed. 
diff --git a/keyboards/ploopyco/trackball_thumb/rev1_001/config.h b/keyboards/ploopyco/trackball_thumb/rev1_001/config.h
new file mode 100644
index 00000000000..dc80d9401eb
--- /dev/null
+++ b/keyboards/ploopyco/trackball_thumb/rev1_001/config.h
@@ -0,0 +1,24 @@
+/* Copyright 2021 Colin Lam (Ploopy Corporation)
+ * Copyright 2020 Christopher Courtney, aka Drashna Jael're  (@drashna) <drashna@live.com>
+ * Copyright 2019 Sunjun Kim
+ *
+ * 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 2 of the License, or
+ * (at your option) 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.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#pragma once
+
+// These pins are not broken out, and cannot be used normally.
+// They are set as output and pulled high, by default
+#define UNUSED_PINS \
+    { D1, D3, B4, B7, D6, C7, F6, F5, F3, F7 }
diff --git a/keyboards/ploopyco/trackball_thumb/rev1_001/info.json b/keyboards/ploopyco/trackball_thumb/rev1_001/info.json
new file mode 100644
index 00000000000..80951b5b2dd
--- /dev/null
+++ b/keyboards/ploopyco/trackball_thumb/rev1_001/info.json
@@ -0,0 +1,20 @@
+{
+    "usb": {
+        "device_version": "1.0.0"
+    },
+    "diode_direction": "COL2ROW",
+    "matrix_pins": {
+        "direct": [ [ "D5", "B6", "D4", "D2", "E6", "D7" ] ]
+    },
+    "rgblight": {
+        "led_count": 3,
+        "pin": "B5",
+        "max_brightness": 40,
+        "animations": {
+            "breathing": true,
+            "rainbow_mood": true,
+            "rainbow_swirl": true
+        }
+    }
+
+}
diff --git a/keyboards/ploopyco/trackball_thumb/rev1_001/readme.md b/keyboards/ploopyco/trackball_thumb/rev1_001/readme.md
new file mode 100644
index 00000000000..5a5f0563e76
--- /dev/null
+++ b/keyboards/ploopyco/trackball_thumb/rev1_001/readme.md
@@ -0,0 +1,3 @@
+This is the R1.001+ version of the Thumb. Future versions may have other features.
+
+See the [main readme](../readme.md) for more details. 
diff --git a/keyboards/ploopyco/trackball_thumb/rev1_001/rev1_001.h b/keyboards/ploopyco/trackball_thumb/rev1_001/rev1_001.h
new file mode 100644
index 00000000000..f43818665cf
--- /dev/null
+++ b/keyboards/ploopyco/trackball_thumb/rev1_001/rev1_001.h
@@ -0,0 +1,21 @@
+/* Copyright Colin Lam (Ploopy Corporation)
+ * Copyright 2020 Christopher Courtney, aka Drashna Jael're  (@drashna) <drashna@live.com>
+ * Copyright 2019 Sunjun Kim
+ *
+ * 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 2 of the License, or
+ * (at your option) 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.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#pragma once
+
+#include "trackball_thumb.h"
diff --git a/keyboards/ploopyco/trackball_thumb/rev1_001/rules.mk b/keyboards/ploopyco/trackball_thumb/rev1_001/rules.mk
new file mode 100644
index 00000000000..e69de29bb2d
diff --git a/keyboards/ploopyco/trackball_thumb/rules.mk b/keyboards/ploopyco/trackball_thumb/rules.mk
new file mode 100644
index 00000000000..4a16c0abfbe
--- /dev/null
+++ b/keyboards/ploopyco/trackball_thumb/rules.mk
@@ -0,0 +1,9 @@
+# Processor frequency
+F_CPU = 8000000
+
+POINTING_DEVICE_DRIVER = pmw3360
+
+QUANTUM_LIB_SRC += analog.c
+SRC += opt_encoder.c
+
+DEFAULT_FOLDER = ploopyco/trackball_thumb/rev1_001
diff --git a/keyboards/ploopyco/trackball_thumb/trackball_thumb.c b/keyboards/ploopyco/trackball_thumb/trackball_thumb.c
new file mode 100644
index 00000000000..f76d243f18c
--- /dev/null
+++ b/keyboards/ploopyco/trackball_thumb/trackball_thumb.c
@@ -0,0 +1,229 @@
+/* Copyright 2021 Colin Lam (Ploopy Corporation)
+ * Copyright 2020 Christopher Courtney, aka Drashna Jael're  (@drashna) <drashna@live.com>
+ * Copyright 2019 Sunjun Kim
+ *
+ * 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 2 of the License, or
+ * (at your option) 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.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "trackball_thumb.h"
+
+#ifndef OPT_DEBOUNCE
+#    define OPT_DEBOUNCE 5  // (ms) 			Time between scroll events
+#endif
+#ifndef SCROLL_BUTT_DEBOUNCE
+#    define SCROLL_BUTT_DEBOUNCE 100  // (ms) 			Time between scroll events
+#endif
+#ifndef PLOOPY_DPI_OPTIONS
+#    define PLOOPY_DPI_OPTIONS \
+        { 600, 900, 1200, 1600 }
+#    ifndef PLOOPY_DPI_DEFAULT
+#        define PLOOPY_DPI_DEFAULT 1
+#    endif
+#endif
+#ifndef PLOOPY_DPI_DEFAULT
+#    define PLOOPY_DPI_DEFAULT 0
+#endif
+#ifndef PLOOPY_DRAGSCROLL_DPI
+#    define PLOOPY_DRAGSCROLL_DPI 100  // Fixed-DPI Drag Scroll
+#endif
+#ifndef PLOOPY_DRAGSCROLL_MULTIPLIER
+#    define PLOOPY_DRAGSCROLL_MULTIPLIER 0.75  // Variable-DPI Drag Scroll
+#endif
+
+keyboard_config_t keyboard_config;
+uint16_t          dpi_array[] = PLOOPY_DPI_OPTIONS;
+#define DPI_OPTION_SIZE (sizeof(dpi_array) / sizeof(uint16_t))
+
+// TODO: Implement libinput profiles
+// https://wayland.freedesktop.org/libinput/doc/latest/pointer-acceleration.html
+// Compile time accel selection
+// Valid options are ACC_NONE, ACC_LINEAR, ACC_CUSTOM, ACC_QUADRATIC
+
+// Trackball State
+bool     is_scroll_clicked = false;
+uint16_t last_scroll       = 0;  // Previous confirmed wheel event
+uint16_t last_mid_click    = 0;  // Stops scrollwheel from being read if it was pressed;
+bool     debug_encoder     = false;
+bool     is_drag_scroll    = false;
+
+// require, since core encoder.c (where is is normally defined isn't present
+__attribute__((weak)) bool encoder_update_user(uint8_t index, bool clockwise) { return true; }
+
+bool encoder_update_kb(uint8_t index, bool clockwise) {
+    if (!encoder_update_user(index, clockwise)) {
+        return false;
+    }
+#ifdef MOUSEKEY_ENABLE
+    tap_code(clockwise ? KC_WH_U : KC_WH_D);
+#else
+    mouse_report_t mouse_report = pointing_device_get_report();
+    mouse_report.v              = clockwise ? 1 : -1;
+    pointing_device_set_report(mouse_report);
+    pointing_device_send();
+#endif
+    return true;
+}
+
+void encoder_init(void) { opt_encoder_init(); }
+
+bool encoder_read(void) {
+    // Lovingly ripped from the Ploopy Source
+
+    // If the mouse wheel was just released, do not scroll.
+    if (timer_elapsed(last_mid_click) < SCROLL_BUTT_DEBOUNCE) {
+        return false;
+    }
+
+    // Limit the number of scrolls per unit time.
+    if (timer_elapsed(last_scroll) < OPT_DEBOUNCE) {
+        return false;
+    }
+
+    // Don't scroll if the middle button is depressed.
+    if (is_scroll_clicked) {
+#ifndef IGNORE_SCROLL_CLICK
+        return false;
+#endif
+    }
+
+    last_scroll = timer_read();
+    uint16_t p1 = adc_read(OPT_ENC1_MUX);
+    uint16_t p2 = adc_read(OPT_ENC2_MUX);
+    if (debug_encoder) dprintf("OPT1: %d, OPT2: %d\n", p1, p2);
+
+    int dir = opt_encoder_handler(p1, p2);
+
+    if (dir == 0) return false;
+    ;
+    encoder_update_kb(0, dir == 1);
+    return true;
+}
+
+report_mouse_t pointing_device_task_kb(report_mouse_t mouse_report) {
+    if (is_drag_scroll) {
+        mouse_report.h = mouse_report.x;
+#ifdef PLOOPY_DRAGSCROLL_INVERT
+        // Invert vertical scroll direction
+        mouse_report.v = -mouse_report.y;
+#else
+        mouse_report.v = mouse_report.y;
+#endif
+        mouse_report.x = 0;
+        mouse_report.y = 0;
+    }
+
+    return pointing_device_task_user(mouse_report);
+}
+
+bool process_record_kb(uint16_t keycode, keyrecord_t* record) {
+    // Update Timer to prevent accidental scrolls
+    if ((record->event.key.col == 1) && (record->event.key.row == 0)) {
+        last_mid_click    = timer_read();
+        is_scroll_clicked = record->event.pressed;
+    }
+
+    if (!process_record_user(keycode, record)) {
+        return false;
+    }
+
+    if (keycode == DPI_CONFIG && record->event.pressed) {
+        keyboard_config.dpi_config = (keyboard_config.dpi_config + 1) % DPI_OPTION_SIZE;
+        eeconfig_update_kb(keyboard_config.raw);
+        pointing_device_set_cpi(dpi_array[keyboard_config.dpi_config]);
+    }
+
+    if (keycode == DRAG_SCROLL) {
+#ifndef PLOOPY_DRAGSCROLL_MOMENTARY
+        if (record->event.pressed)
+#endif
+        {
+            is_drag_scroll ^= 1;
+        }
+#ifdef PLOOPY_DRAGSCROLL_FIXED
+        pointing_device_set_cpi(is_drag_scroll ? PLOOPY_DRAGSCROLL_DPI : dpi_array[keyboard_config.dpi_config]);
+#else
+        pointing_device_set_cpi(is_drag_scroll ? (dpi_array[keyboard_config.dpi_config] * PLOOPY_DRAGSCROLL_MULTIPLIER) : dpi_array[keyboard_config.dpi_config]);
+#endif
+    }
+
+/* If Mousekeys is disabled, then use handle the mouse button
+ * keycodes.  This makes things simpler, and allows usage of
+ * the keycodes in a consistent manner.  But only do this if
+ * Mousekeys is not enable, so it's not handled twice.
+ */
+#ifndef MOUSEKEY_ENABLE
+    if (IS_MOUSEKEY_BUTTON(keycode)) {
+        report_mouse_t currentReport = pointing_device_get_report();
+        if (record->event.pressed) {
+            currentReport.buttons |= 1 << (keycode - KC_MS_BTN1);
+        } else {
+            currentReport.buttons &= ~(1 << (keycode - KC_MS_BTN1));
+        }
+        pointing_device_set_report(currentReport);
+        pointing_device_send();
+    }
+#endif
+
+    return true;
+}
+
+// Hardware Setup
+void keyboard_pre_init_kb(void) {
+    // debug_enable  = true;
+    // debug_matrix  = true;
+    // debug_mouse   = true;
+    // debug_encoder = true;
+
+    setPinInput(OPT_ENC1);
+    setPinInput(OPT_ENC2);
+
+    /* Ground all output pins connected to ground. This provides additional
+     * pathways to ground. If you're messing with this, know this: driving ANY
+     * of these pins high will cause a short. On the MCU. Ka-blooey.
+     */
+#ifdef UNUSED_PINS
+    const pin_t unused_pins[] = UNUSED_PINS;
+
+    for (uint8_t i = 0; i < (sizeof(unused_pins) / sizeof(pin_t)); i++) {
+        setPinOutput(unused_pins[i]);
+        writePinLow(unused_pins[i]);
+    }
+#endif
+
+    // This is the debug LED.
+#if defined(DEBUG_LED_PIN)
+    setPinOutput(DEBUG_LED_PIN);
+    writePin(DEBUG_LED_PIN, debug_enable);
+#endif
+
+    keyboard_pre_init_user();
+}
+
+void pointing_device_init_kb(void) { pointing_device_set_cpi(dpi_array[keyboard_config.dpi_config]); }
+
+void eeconfig_init_kb(void) {
+    keyboard_config.dpi_config = PLOOPY_DPI_DEFAULT;
+    eeconfig_update_kb(keyboard_config.raw);
+    eeconfig_init_user();
+}
+
+void matrix_init_kb(void) {
+    // is safe to just read DPI setting since matrix init
+    // comes before pointing device init.
+    keyboard_config.raw = eeconfig_read_kb();
+    if (keyboard_config.dpi_config > DPI_OPTION_SIZE) {
+        eeconfig_init_kb();
+    }
+    matrix_init_user();
+}
diff --git a/keyboards/ploopyco/trackball_thumb/trackball_thumb.h b/keyboards/ploopyco/trackball_thumb/trackball_thumb.h
new file mode 100644
index 00000000000..168e8940640
--- /dev/null
+++ b/keyboards/ploopyco/trackball_thumb/trackball_thumb.h
@@ -0,0 +1,60 @@
+/* Copyright 2021 Colin Lam (Ploopy Corporation)
+ * Copyright 2020 Christopher Courtney, aka Drashna Jael're  (@drashna) <drashna@live.com>
+ * Copyright 2019 Sunjun Kim
+ *
+ * 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 2 of the License, or
+ * (at your option) 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.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#pragma once
+
+#include "quantum.h"
+#include "analog.h"
+#include "opt_encoder.h"
+#if defined(KEYBOARD_ploopyco_trackball_thumb_rev1_001)
+#    include "rev1_001.h"
+#endif
+
+// Sensor defs
+#define OPT_ENC1 F4
+#define OPT_ENC2 F0
+#define OPT_ENC1_MUX 4
+#define OPT_ENC2_MUX 0
+
+bool encoder_update_kb(uint8_t index, bool clockwise);
+bool encoder_update_user(uint8_t index, bool clockwise);
+
+typedef union {
+    uint32_t raw;
+    struct {
+        uint8_t dpi_config;
+    };
+} keyboard_config_t;
+_Static_assert(sizeof(keyboard_config_t) == sizeof(uint32_t), "keyboard_config_t size mismatch compared to EEPROM area");
+
+extern keyboard_config_t keyboard_config;
+extern uint16_t          dpi_array[];
+
+enum ploopy_keycodes {
+#ifdef VIA_ENABLE
+    DPI_CONFIG = USER00,
+#else
+    DPI_CONFIG = SAFE_RANGE,
+#endif
+    DRAG_SCROLL,
+#ifdef VIA_ENABLE
+    PLOOPY_SAFE_RANGE = SAFE_RANGE,
+#else
+    PLOOPY_SAFE_RANGE,
+#endif
+};