diff --git a/keyboards/crkbd/keymaps/md40/config.h b/keyboards/crkbd/keymaps/md40/config.h
new file mode 100644
index 000000000000..c1ef28df50ec
--- /dev/null
+++ b/keyboards/crkbd/keymaps/md40/config.h
@@ -0,0 +1,41 @@
+/*
+This is the c configuration file for the keymap
+
+Copyright 2012 Jun Wako <wakojun@gmail.com>
+Copyright 2015 Jack Humbert
+
+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 TAPPING_FORCE_HOLD
+#define TAPPING_TERM 300
+
+#undef RGBLED_NUM
+#define RGBLIGHT_EFFECT_BREATHING
+#define RGBLIGHT_EFFECT_RAINBOW_MOOD
+#define RGBLIGHT_EFFECT_RAINBOW_SWIRL
+#define RGBLIGHT_EFFECT_SNAKE
+#define RGBLIGHT_EFFECT_KNIGHT
+#define RGBLIGHT_EFFECT_CHRISTMAS
+#define RGBLIGHT_EFFECT_STATIC_GRADIENT
+#define RGBLIGHT_EFFECT_RGB_TEST
+#define RGBLIGHT_EFFECT_ALTERNATING
+#define RGBLIGHT_EFFECT_TWINKLE
+#define RGBLED_NUM 27
+#define RGBLIGHT_LIMIT_VAL 120
+#define RGBLIGHT_HUE_STEP 10
+#define RGBLIGHT_SAT_STEP 17
+#define RGBLIGHT_VAL_STEP 17
diff --git a/keyboards/crkbd/keymaps/md40/keymap.c b/keyboards/crkbd/keymaps/md40/keymap.c
new file mode 100644
index 000000000000..39ae0bb4e0ba
--- /dev/null
+++ b/keyboards/crkbd/keymaps/md40/keymap.c
@@ -0,0 +1,38 @@
+// Copyright 2021 Shane Dowling (@shano)
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+#include QMK_KEYBOARD_H
+#define KC_ESCC MT(MOD_LCTL, KC_ESC)
+#define KC_ENTS MT(MOD_LSFT, KC_ENT)
+#define KC_FN   MO(_FN)
+
+enum layers {
+  _QWERTY,
+  _FN,
+};
+
+const uint16_t PROGMEM keymaps[][MATRIX_ROWS][MATRIX_COLS] = {
+  [_QWERTY] = LAYOUT(
+  //,----+----+----+----+----+----.              ,----+----+----+----+----+----.
+     KC_TAB , KC_Q  , KC_W  , KC_E  , KC_R  , KC_T  ,                KC_Y  , KC_U  , KC_I  , KC_O  , KC_P  ,KC_BSPC,
+  //|----+----+----+----+----+----|              |----+----+----+----+----+----|
+     KC_LSFT, KC_A  , KC_S  , KC_D  , KC_F  , KC_G  ,                KC_H  , KC_J  , KC_K  , KC_L  ,KC_SCLN,KC_QUOT,
+     //|----+----+----+----+----+----+              |----+----+----+----+----+----|
+     KC_ESCC, KC_Z  , KC_X  , KC_C  , KC_V  , KC_B  ,                KC_N  , KC_M  ,KC_COMM,KC_DOT ,KC_SLSH,KC_ESC ,
+  //`----+----+----+--+-+----+----+----/    \----+----+----+----+----+----+----'
+                       KC_LALT,KC_LGUI,KC_SPC ,         KC_ENTS,KC_FN,KC_FN
+  //                  `----+----+----'        `+---+----+----'c
+  ),
+  [_FN] = LAYOUT(
+  //,----+----+----+----+----+----.              ,----+----+----+----+----+----.
+     _______,KC_1, KC_2 ,KC_3, KC_4,KC_5,               KC_6,KC_7,KC_8,KC_9,KC_0,KC_BSPC,
+  //|----+----+----+----+----+----|              |----+----+----+----+----+----|
+     _______,KC_EXCLAIM,KC_AT,KC_HASH,KC_DOLLAR,KC_PERCENT,      KC_LEFT,KC_DOWN, KC_UP ,KC_RIGHT,KC_LBRC,KC_RBRC,
+  //|----+----+----+----+----+----+              |----+----+----+----+----+----|
+     _______, KC_CIRCUMFLEX  , KC_AMPR  , KC_ASTERISK  , KC_LEFT_PAREN  , KC_RIGHT_PAREN  ,               KC_MINUS,KC_PLUS,KC_EQL,KC_PIPE,KC_GRAVE,KC_BACKSLASH,
+  //`----+----+----+--+-+----+----+----/    \----+----+----+----+----+----+----'
+                       _______,_______,_______ ,         _______,_______,_______
+  //                  `----+----+----'        `----+----+----'
+  )
+};
+
diff --git a/keyboards/crkbd/keymaps/md40/readme.md b/keyboards/crkbd/keymaps/md40/readme.md
new file mode 100644
index 000000000000..ee1e14a0165a
--- /dev/null
+++ b/keyboards/crkbd/keymaps/md40/readme.md
@@ -0,0 +1,19 @@
+# MD40: Minimally Disruptive 40% Keymap
+
+This keymap is an attempt to go from a standard keyboard layout to a 40% keyboard with minimal disruption.
+
+Some aims:
+- Two layers only
+- Existing keyboard positions where possible
+- Exceptions where it's not possible
+- Exceptions where it makes sense
+
+Supports crkbd only.
+
+## Base Layer
+
+![Base Layer](https://i.imgur.com/hXLP6ush.png)
+
+## Fn Layer
+
+![Base Layer](https://i.imgur.com/Sozd1p8h.png)
diff --git a/keyboards/crkbd/keymaps/md40/rules.mk b/keyboards/crkbd/keymaps/md40/rules.mk
new file mode 100644
index 000000000000..86f4f1e11c01
--- /dev/null
+++ b/keyboards/crkbd/keymaps/md40/rules.mk
@@ -0,0 +1,8 @@
+
+# Build Options
+#   change to "no" to disable the options, or define them in the Makefile in
+#   the appropriate keymap folder that will get included automatically
+#
+BOOTMAGIC_ENABLE = no       # Enable Bootmagic Lite
+MOUSEKEY_ENABLE = no        # Mouse keys
+NKRO_ENABLE = no            # Enable N-Key Rollover