diff --git a/keyboards/kbd67/hotswap/keymaps/zunger/config.h b/keyboards/kbd67/hotswap/keymaps/zunger/config.h
new file mode 100644
index 0000000000..cc06440e0d
--- /dev/null
+++ b/keyboards/kbd67/hotswap/keymaps/zunger/config.h
@@ -0,0 +1,22 @@
+/* Copyright 2018 MechMerlin
+ *
+ * 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 .
+ */
+
+#pragma once
+
+// Enable cmd-option-escape on mac.
+#define GRAVE_ESC_ALT_OVERRIDE
+
+// place overrides here
diff --git a/keyboards/kbd67/hotswap/keymaps/zunger/keymap.c b/keyboards/kbd67/hotswap/keymaps/zunger/keymap.c
new file mode 100644
index 0000000000..0d542bf843
--- /dev/null
+++ b/keyboards/kbd67/hotswap/keymaps/zunger/keymap.c
@@ -0,0 +1,176 @@
+/* Copyright 2019 Yonatan Zunger
+ *
+ * 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 .
+ */
+#include QMK_KEYBOARD_H
+
+enum custom_keycodes {
+ // Use this instead of RALT, so we can use it to switch layers but not trigger other alt-related
+ // behavior (like GRAVE_ESC_ALT_OVERRIDE).
+ MAGIC = SAFE_RANGE,
+};
+
+enum layers_keymap {
+ _QWERTY = 0,
+ _FUNCTION,
+
+ _MAGIC,
+ _SHIFTMAGIC,
+};
+
+// This is so that H(xxxx) has the same width as _______, which makes the grids more legible.
+#define H(x) UC(0x##x)
+
+
+const uint16_t PROGMEM keymaps[][MATRIX_ROWS][MATRIX_COLS] = {
+/* Keymap (Base Layer) Default Layer
+ * ,----------------------------------------------------------------.
+ * |Esc | 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| -| =|Del|Brk|Home|
+ * |----------------------------------------------------------------|
+ * |Tab | Q| W| E| R| T| Y| U| I| O| P| [| ]| \ |End |
+ * |----------------------------------------------------------------|
+ * |Ctrl | A| S| D| F| G| H| J| K| L| ;| '|Return |PgUp|
+ * |----------------------------------------------------------------|
+ * |Shift | Z| X| C| V| B| N| M| ,| .| /|Shift | Up|PgDn|
+ * |----------------------------------------------------------------|
+ * |Ctrl|Alt |Win | Space |Alt| FN |||||Lef|Dow|Rig |
+ * `----------------------------------------------------------------'
+ */
+[_QWERTY] = LAYOUT(
+ KC_GESC, 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_BRK, KC_HOME, \
+ 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_END, \
+ KC_LCTL, 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_PGUP, \
+ 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_PGDN, \
+ KC_LCTL, KC_LALT, KC_LGUI, KC_SPC, MAGIC, MO(_FUNCTION), KC_LEFT, KC_DOWN, KC_RGHT),
+
+ /* Keymap Fn Layer. Blank keys are deliberately NO, not TRNS.
+ * ,----------------------------------------------------------------.
+ * |Rst |F1| F2| F3| F4| F5| F6| F7| F8| F9|F10|F11|F12|F13|PSc|PAUS|
+ * |----------------------------------------------------------------|
+ * |Debug| | | | | | | | | | | | | | |
+ * |----------------------------------------------------------------|
+ * |Ctrl | |Vo+| | | | | | | | | | | |
+ * |----------------------------------------------------------------|
+ * |Shift |REV|Vo-|FWD| | | | | | | | McL|MsU|McR |
+ * |----------------------------------------------------------------|
+ * |Ctrl|Alt |Win | |Alt| |||||MsL|MsD|MsR |
+ * `----------------------------------------------------------------'
+ */
+[_FUNCTION] = LAYOUT(
+ RESET, 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_F13, KC_PSCR, KC_MPLY, \
+ DEBUG, KC_NO, KC_NO, KC_NO, KC_NO, KC_NO, KC_NO, KC_NO, KC_NO, KC_NO, KC_NO, KC_NO, KC_NO, KC_NO, _______, \
+ _______, KC_NO, KC__VOLUP, KC_NO, KC_NO, KC_NO, KC_NO, KC_NO, KC_NO, KC_NO, KC_NO, KC_NO, KC_NO, KC_NO, \
+ _______, KC_MRWD, KC__VOLDOWN, KC_MFFD, KC_NO, KC_NO, KC_NO, KC_NO, KC_NO, KC_NO, KC_NO, KC_BTN1, KC_MS_U, KC_BTN2, \
+ _______, _______, _______, KC_NO, _______, _______, KC_MS_L, KC_MS_D, KC_MS_R),
+
+ /* Mathematical lower layer. Blank keys are TRNS.
+ * Note that escape turns into grave here. This doesn't just generalize GRAVE_ESC; it means that
+ * magic+esc is a way to create backticks without a dedicated key.
+ * ,----------------------------------------------------------------.
+ * | ` | ¹| ² | ³ | ⁴ | ⁵ | ⁶ | ⁷ | ⁸ | ⁹ | ⁰ | ⁻ | ⁺ | ⊕ | ≠ | √ |
+ * |----------------------------------------------------------------|
+ * | | ± | ω | ε | ρ | τ | θ | υ | ι | ο | π | ∃ | ∀ | ℚ | ℝ |
+ * |----------------------------------------------------------------|
+ * | | α | σ | δ | φ | γ | η | ∅ | κ | λ | ∨ | ∧ | | ℕ |
+ * |----------------------------------------------------------------|
+ * | | ζ | ξ | χ | ψ | β | ν | μ | ≲ | ≳ | ∈ | | ↑ | ↔ |
+ * |----------------------------------------------------------------|
+ * | | | | | | ||||| ← | ↓ | → |
+ * `----------------------------------------------------------------'
+ */
+[_MAGIC] = LAYOUT(
+ KC_GRV, H(00b9), H(00b2), H(00b3), H(2074), H(2075), H(2076), H(2077), H(2078), H(2079), H(2070), H(207b), H(207a), H(2295), H(2260), H(221a), \
+ _______, H(00b1), H(03c9), H(03b5), H(03c1), H(03c4), H(03b8), H(03c5), H(03b9), H(03bf), H(03c0), H(2203), H(2200), H(211a), H(211d), \
+ _______, H(03b1), H(03c3), H(03b4), H(03c6), H(03b3), H(03b7), H(2205), H(03ba), H(03bb), H(2228), H(2227), _______, H(2115), \
+ _______, H(03b6), H(03be), H(03c7), H(03c8), H(03b2), H(03bd), H(03bc), H(2272), H(2273), H(2208), _______, H(2191), H(2194), \
+ _______, _______, _______, _______, _______, _______, H(2190), H(2193), H(2192)),
+
+ /* Mathematical upper layer. Blank keys are TRNS.
+ * ,----------------------------------------------------------------.
+ * | ` | ₁| ₂ | ₃ | ₄ | ₅ | ₆ | ₇ | ₈ | ₉ | ₀ | ₋ | ₊ | ⊗ | ≈ | ∂ |
+ * |----------------------------------------------------------------|
+ * | | ∓ | Ω | Ε | Ρ | Τ | Θ | Υ | Ι | Ο | Π | ∄ | ∞ | ⊙ | ℂ |
+ * |----------------------------------------------------------------|
+ * | | Α | Σ | Δ | Φ | Γ | Η | ¬ | Κ | Λ | ∪ | ∩ | | ℤ |
+ * |----------------------------------------------------------------|
+ * | | Ζ | Ξ | Χ | Ψ | Β | Ν | Μ | ⊆ | ⊇ | ∉ | | ⇑ | ⇔ |
+ * |----------------------------------------------------------------|
+ * | | | | | | ||||| ⇐ | ⇓ | ⇒ |
+ * `----------------------------------------------------------------'
+ */
+[_SHIFTMAGIC] = LAYOUT(
+ KC_GRV, H(2081), H(2082), H(2083), H(2084), H(2085), H(2086), H(2087), H(2088), H(2089), H(2080), H(208b), H(208a), H(2297), H(2248), H(2202), \
+ _______, H(2213), H(03a9), H(0395), H(03a1), H(03a4), H(0398), H(03a5), H(0399), H(039f), H(03a0), H(2204), H(221e), H(2299), H(2102), \
+ _______, H(0391), H(03a3), H(0394), H(03a6), H(0393), H(0397), H(00ac), H(039a), H(039b), H(222a), H(2229), _______, H(2124), \
+ _______, H(0396), H(039e), H(03a7), H(03a8), H(0392), H(039d), H(039c), H(2286), H(2287), H(2209), _______, H(21d1), H(21d4), \
+ _______, _______, _______, _______, _______, _______, H(21d0), H(21d3), H(21d2)),
+};
+
+// Layer bitfields.
+#define MAGIC_LAYER (1UL << _MAGIC)
+#define SHIFTMAGIC_LAYER (1UL << _SHIFTMAGIC)
+// The layers we don't touch.
+#define LAYER_MASK ~(MAGIC_LAYER|SHIFTMAGIC_LAYER)
+
+bool process_record_user(uint16_t keycode, keyrecord_t *record) {
+ // Activate the appropriate magic layer:
+ // User is holding AltGr+Shift => _SHIFTMAGIC
+ // User is holding AltGr => _MAGIC
+ // Not holding AltGr => None
+ // We do this the efficient way, by grabbing the non-magic bits from the current layer bitmap,
+ // setting the appropriate magic or shiftmagic bit, and doing an absolute layer set. (Layer
+ // sets are nontrivial, so we don't want to do extras!)
+
+ // We track shift and AltGr state on our own, because this function is called before get_mods is
+ // updated!
+ static bool shifted = false;
+ static bool magic = false;
+
+ if (keycode == KC_LSHIFT || keycode == KC_RSHIFT) {
+ shifted = record->event.pressed;
+ } else if (keycode == MAGIC) {
+ magic = record->event.pressed;
+ } else if (keycode == RESET) {
+ // Safe reset: Only actually let this keycode through if shift is held as well. Since there's no
+ // right-shift in the function layer, this means that reset is Fn+LShift+Esc, something you're
+ // not likely to hit by accident. (Especially since AltGr+Esc is backtick!)
+ return (record->event.pressed && shifted);
+ }
+
+ // Update the layer.
+ uint32_t new_layer_state = layer_state & LAYER_MASK;
+ if (magic) {
+ new_layer_state |= (shifted ? SHIFTMAGIC_LAYER : MAGIC_LAYER);
+ }
+ if (layer_state != new_layer_state) {
+ layer_state_set(new_layer_state);
+ }
+
+ return true;
+}
+
+void eeconfig_init_user(void) {
+ set_unicode_input_mode(UC_OSX);
+}
+
+void matrix_init_user(void) {
+}
+
+void matrix_scan_user(void) {
+
+}
+
+void led_set_user(uint8_t usb_led) {
+
+}
diff --git a/keyboards/kbd67/hotswap/keymaps/zunger/readme.md b/keyboards/kbd67/hotswap/keymaps/zunger/readme.md
new file mode 100644
index 0000000000..923a4824a5
--- /dev/null
+++ b/keyboards/kbd67/hotswap/keymaps/zunger/readme.md
@@ -0,0 +1,27 @@
+* Custom keymap for kbd67, for those who need to both code and type math.
+* Author: Yonatan Zunger (zunger@gmail.com)
+
+This keymap is presently rather Mac-centric, as it uses Mac media keys in its function layer and the
+OS X Unicode input mode for the "magic" layers.
+
+*Layer 0 (Base QWERTY):* The layout has a few minor quirks: grave escape, Home/End/PgUp/PgDn in the
+right-hand column (rather than the more common Home/PgUp/PgDn/End), and a pause key between
+backspace and home -- this being something I use for screen lock, a necessity when one works with
+and sits next to security engineers. (Using a heavier switch on the pause key greatly reduces the
+risk of accidental triggering) In OS X style, alt and win are swapped on the left-hand side.
+
+The right-hand alt and gui keys take on a different meaning: right-alt lives up to its old name of
+AltGr by invoking Greek (the "magic" layers, 2 and 3), and right-gui invokes the function layer.
+
+*Layer 1 (Functions):* This layer deliberately sets KC_NO for the keys it doesn't use. I realize
+this isn't common, but I like to keep my functions quite distinct from all other layers.
+
+RESET can be accessed at Fn+Left Shift+Escape.
+
+*Layers 2 and 3*: These are invoked by the "magic" key (AltGr) and by magic+shift. The
+letters mostly produce Greek; the numbers, superscripts (magic) and subscripts (magic+shift); and
+the various other keys, mathematical symbols. There unfortunately aren't nearly enough keys for all
+the symbols I'd like, so magic+alt and magic+alt+shift may end up existing as well, giving this a
+proper Space Cadet effect; but that said, it's going to be hard to remember where all these symbols
+are without some extremely custom keycaps. In the limit of arbitrarily complex layers, the keyboard
+will probably start running LISP and turn into EMACS.
diff --git a/keyboards/kbd67/hotswap/keymaps/zunger/rules.mk b/keyboards/kbd67/hotswap/keymaps/zunger/rules.mk
new file mode 100644
index 0000000000..a61cfa33fa
--- /dev/null
+++ b/keyboards/kbd67/hotswap/keymaps/zunger/rules.mk
@@ -0,0 +1,2 @@
+# You need Unicode for this map.
+UNICODE_ENABLE = yes # Unicode