diff --git a/keyboards/atreus/keymaps/default/keymap.c b/keyboards/atreus/keymaps/default/keymap.c
index e0db1bdc3c..4964ecadb2 100644
--- a/keyboards/atreus/keymaps/default/keymap.c
+++ b/keyboards/atreus/keymaps/default/keymap.c
@@ -14,23 +14,40 @@
 #define RALT_SCLN RALT_T(KC_SCLN)
 
 #define I_SPC LT(1, KC_SPC)
+#define I_BSPC LT(2, KC_BSPC)
+
+// https://github.com/callum-oakley/qmk_firmware/tree/master/users/callum
 
 const uint16_t PROGMEM keymaps[][MATRIX_ROWS][MATRIX_COLS] = {
   [0] = LAYOUT(
-    KC_Q,   KC_W,   KC_E,   KC_R,   KC_T,                     KC_Y,   KC_U,   KC_I,   KC_O,  KC_P     ,
-    RALT_A, ALT_S,  CTL_D,  GUI_F,  KC_G,                     KC_H,   GUI_J,  CTL_K,  ALT_L, RALT_SCLN,
-    KC_Z,   KC_X,   KC_C,   KC_V,   KC_B,    KC_GRV, KC_BSLS, KC_N,   KC_M,   KC_COMM,KC_DOT,KC_SLSH  ,
-    KC_ESC, KC_TAB, XXXXXXX,KC_LSFT,KC_BSPC, XXXXXXX,XXXXXXX, I_SPC,  XXXXXXX,KC_MINS,KC_QUOT,KC_ENT)  ,
+    KC_Q,   KC_W,   KC_E,   KC_R,   KC_T,                     KC_Y,   KC_U,   KC_I,   KC_O,   KC_P,
+    RALT_A, ALT_S,  CTL_D,  GUI_F,  KC_G,                     KC_H,   GUI_J,  CTL_K,  ALT_L,  RALT_SCLN,
+    KC_Z,   KC_X,   KC_C,   KC_V,   KC_B,    KC_GRV, KC_BSLS, KC_N,   KC_M,   KC_COMM,KC_DOT, KC_SLSH,
+    KC_ESC, KC_TAB, XXXXXXX,KC_LSFT,I_BSPC,  XXXXXXX,XXXXXXX, KC_SPC, MO(1),  XXXXXXX,XXXXXXX,XXXXXXX
+  ),
 
   [1] = LAYOUT(
-    KC_EXLM,KC_AT,  KC_UP,  KC_DLR, KC_PERC,                  KC_PGUP,KC_7,   KC_8,   KC_9,  KC_BSPC,
-    KC_LPRN,KC_LEFT,KC_DOWN,KC_RGHT,KC_RPRN,                  KC_PGDN,KC_4,   KC_5,   KC_6,  _______,
-    KC_LBRC,KC_RBRC,KC_HASH,KC_LCBR,KC_RCBR, KC_CIRC,KC_AMPR, KC_ASTR,KC_1,   KC_2,   KC_3,  KC_PLUS,
-    TO(2),  KC_INS, _______,KC_LSFT,KC_BSPC, XXXXXXX,XXXXXXX, _______,_______,KC_DOT, KC_0,  KC_EQL),
+    KC_ESC, KC_EXLM,KC_AT,  KC_DLR, KC_PERC,                  KC_PLUS,KC_7,   KC_8,   KC_9,   XXXXXXX,
+    KC_LPRN,KC_MINS,KC_QUOT,KC_EQL, KC_RPRN,                  KC_0,   KC_1,   KC_2,   KC_3,   KC_BSPC,
+    KC_LBRC,KC_RBRC,KC_HASH,KC_LCBR,KC_RCBR, KC_CIRC,KC_AMPR, KC_ASTR,KC_4,   KC_5,   KC_6,   KC_ENT,
+    XXXXXXX,XXXXXXX,_______,_______,_______, XXXXXXX,XXXXXXX, _______,_______,KC_DOT, XXXXXXX,XXXXXXX
+  ),
 
   [2] = LAYOUT(
-    KC_INS, KC_HOME,KC_UP,  KC_END, KC_PGUP,                  KC_UP,  KC_F7,  KC_F8,  KC_F9, KC_F10  ,
-    KC_DEL, KC_LEFT,KC_DOWN,KC_RGHT,KC_PGDN,                  KC_DOWN,KC_F4,  KC_F5,  KC_F6, KC_F11  ,
-    KC_NO,  KC_VOLU,KC_NO,  KC_NO,  RESET,   _______,_______, KC_NO,  KC_F1,  KC_F2,  KC_F3, KC_F12  ,
-    TO(0),  KC_VOLD,_______,KC_LSFT,KC_BSPC, XXXXXXX,XXXXXXX, _______,TO(0),  KC_PSCR,KC_SLCK,KC_PAUS)
+    KC_TAB, KC_HOME,KC_UP,  KC_END, KC_PGUP,                  KC_UP,  KC_F7,  KC_F8,  KC_F9,  KC_F10,
+    KC_DEL, KC_LEFT,KC_DOWN,KC_RGHT,KC_PGDN,                  KC_LEFT,KC_DOWN,KC_UP,  KC_RGHT,KC_BSPC,
+    KC_NO,  KC_VOLU,KC_NO,  KC_NO,  RESET,   _______,_______, KC_NO,  KC_PGDN,KC_PGUP,KC_F3,  KC_ENT,
+    TO(0),  KC_VOLD,_______,_______,_______, XXXXXXX,XXXXXXX, _______,_______,KC_PSCR,KC_SLCK,KC_PAUS
+  ),
+
+  [3] = LAYOUT(
+    KC_INS, KC_HOME,KC_UP,  KC_END, KC_PGUP,                  KC_UP,  KC_F7,  KC_F8,  KC_F9, KC_F10,
+    KC_DEL, KC_LEFT,KC_DOWN,KC_RGHT,KC_PGDN,                  KC_DOWN,KC_F4,  KC_F5,  KC_F6, KC_F11,
+    KC_NO,  KC_VOLU,KC_NO,  KC_NO,  RESET,   _______,_______, KC_NO,  KC_F1,  KC_F2,  KC_F3, KC_F12,
+    TO(0),  KC_VOLD,_______,_______,_______, XXXXXXX,XXXXXXX, _______,_______,KC_PSCR,KC_SLCK,KC_PAUS
+  )
 };
+
+layer_state_t layer_state_set_user(layer_state_t state) {
+    return update_tri_layer_state(state, 1, 2, 3);
+}