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diff --git a/keyboards/orbekk_dactyl/keymaps/default/features/achordion.c b/keyboards/orbekk_dactyl/keymaps/default/features/achordion.c
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+++ b/keyboards/orbekk_dactyl/keymaps/default/features/achordion.c
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+// Copyright 2022-2023 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     https://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+/**
+ * @file achordion.c
+ * @brief Achordion implementation
+ *
+ * For full documentation, see
+ * <https://getreuer.info/posts/keyboards/achordion>
+ */
+
+#include "achordion.h"
+
+#if !defined(IS_QK_MOD_TAP)
+// Attempt to detect out-of-date QMK installation, which would fail with
+// implicit-function-declaration errors in the code below.
+#error "achordion: QMK version is too old to build. Please update QMK."
+#else
+
+// Copy of the `record` and `keycode` args for the current active tap-hold key.
+static keyrecord_t tap_hold_record;
+static uint16_t tap_hold_keycode = KC_NO;
+// Timeout timer. When it expires, the key is considered held.
+static uint16_t hold_timer = 0;
+// Eagerly applied mods, if any.
+static uint8_t eager_mods = 0;
+// Flag to determine whether another key is pressed within the timeout.
+static bool pressed_another_key_before_release = false;
+
+#ifdef ACHORDION_STREAK
+// Timer for typing streak
+static uint16_t streak_timer = 0;
+#else
+// When disabled, is_streak is never true
+#define is_streak false
+#endif
+
+// Achordion's current state.
+enum {
+  // A tap-hold key is pressed, but hasn't yet been settled as tapped or held.
+  STATE_UNSETTLED,
+  // Achordion is inactive.
+  STATE_RELEASED,
+  // Active tap-hold key has been settled as tapped.
+  STATE_TAPPING,
+  // Active tap-hold key has been settled as held.
+  STATE_HOLDING,
+  // This state is set while calling `process_record()`, which will recursively
+  // call `process_achordion()`. This state is checked so that we don't process
+  // events generated by Achordion and potentially create an infinite loop.
+  STATE_RECURSING,
+};
+static uint8_t achordion_state = STATE_RELEASED;
+
+// Calls `process_record()` with state set to RECURSING.
+static void recursively_process_record(keyrecord_t* record, uint8_t state) {
+  achordion_state = STATE_RECURSING;
+  process_record(record);
+  achordion_state = state;
+}
+
+// Clears eagerly-applied mods.
+static void clear_eager_mods(void) {
+  unregister_mods(eager_mods);
+  eager_mods = 0;
+}
+
+// Sends hold press event and settles the active tap-hold key as held.
+static void settle_as_hold(void) {
+  clear_eager_mods();
+  // Create hold press event.
+  recursively_process_record(&tap_hold_record, STATE_HOLDING);
+}
+
+bool process_achordion(uint16_t keycode, keyrecord_t* record) {
+  // Don't process events that Achordion generated.
+  if (achordion_state == STATE_RECURSING) {
+    return true;
+  }
+
+  // If this is a keypress and if the key is different than the tap-hold key,
+  // this information is saved to a flag to be processed later when the tap-hold
+  // key is released.
+  if (!pressed_another_key_before_release && record->event.pressed &&
+      tap_hold_keycode != KC_NO && tap_hold_keycode != keycode) {
+    pressed_another_key_before_release = true;
+  }
+
+  // Determine whether the current event is for a mod-tap or layer-tap key.
+  const bool is_mt = IS_QK_MOD_TAP(keycode);
+  const bool is_tap_hold = is_mt || IS_QK_LAYER_TAP(keycode);
+  // Check that this is a normal key event, don't act on combos.
+#ifdef IS_KEYEVENT
+  const bool is_key_event = IS_KEYEVENT(record->event);
+#else
+  const bool is_key_event =
+      (record->event.key.row < 254 && record->event.key.col < 254);
+#endif
+
+  if (achordion_state == STATE_RELEASED) {
+    if (is_tap_hold && record->tap.count == 0 && record->event.pressed &&
+        is_key_event) {
+      // A tap-hold key is pressed and considered by QMK as "held".
+      const uint16_t timeout = achordion_timeout(keycode);
+      if (timeout > 0) {
+        achordion_state = STATE_UNSETTLED;
+        // Save info about this key.
+        tap_hold_keycode = keycode;
+        tap_hold_record = *record;
+        hold_timer = record->event.time + timeout;
+
+        if (is_mt) {  // Apply mods immediately if they are "eager."
+          uint8_t mod = mod_config(QK_MOD_TAP_GET_MODS(tap_hold_keycode));
+          if (achordion_eager_mod(mod)) {
+            eager_mods = ((mod & 0x10) == 0) ? mod : (mod << 4);
+            register_mods(eager_mods);
+          }
+        }
+
+        dprintf("Achordion: Key 0x%04X pressed.%s\n", keycode,
+                eager_mods ? " Set eager mods." : "");
+        return false;  // Skip default handling.
+      }
+    }
+
+#ifdef ACHORDION_STREAK
+    streak_timer = (timer_read() + achordion_streak_timeout(keycode)) | 1;
+#endif
+    return true;  // Otherwise, continue with default handling.
+  }
+
+  if (keycode == tap_hold_keycode && !record->event.pressed) {
+    // The active tap-hold key is being released.
+    if (achordion_state == STATE_HOLDING) {
+      dprintln("Achordion: Key released. Plumbing hold release.");
+      tap_hold_record.event.pressed = false;
+      // Plumb hold release event.
+      recursively_process_record(&tap_hold_record, STATE_RELEASED);
+    } else if (!pressed_another_key_before_release) {
+      // No other key was pressed between the press and release of the tap-hold
+      // key, simulate a hold and then a release without waiting for Achordion
+      // timeout to end.
+      dprintln("Achordion: Key released. Simulating hold and release.");
+      settle_as_hold();
+      tap_hold_record.event.pressed = false;
+      // Plumb hold release event.
+      recursively_process_record(&tap_hold_record, STATE_RELEASED);
+    } else {
+      dprintf("Achordion: Key released.%s\n",
+              eager_mods ? " Clearing eager mods." : "");
+      if (is_mt) {
+        clear_eager_mods();
+      }
+    }
+
+    achordion_state = STATE_RELEASED;
+    // The tap-hold key is released, clear the related keycode and the flag.
+    tap_hold_keycode = KC_NO;
+    pressed_another_key_before_release = false;
+    return false;
+  }
+
+  if (achordion_state == STATE_UNSETTLED && record->event.pressed) {
+#ifdef ACHORDION_STREAK
+    const bool is_streak = (streak_timer != 0);
+    streak_timer = (timer_read() + achordion_streak_timeout(keycode)) | 1;
+#endif
+
+    // Press event occurred on a key other than the active tap-hold key.
+
+    // If the other key is *also* a tap-hold key and considered by QMK to be
+    // held, then we settle the active key as held. This way, things like
+    // chording multiple home row modifiers will work, but let's our logic
+    // consider simply a single tap-hold key as "active" at a time.
+    //
+    // Otherwise, we call `achordion_chord()` to determine whether to settle the
+    // tap-hold key as tapped vs. held. We implement the tap or hold by plumbing
+    // events back into the handling pipeline so that QMK features and other
+    // user code can see them. This is done by calling `process_record()`, which
+    // in turn calls most handlers including `process_record_user()`.
+    if (!is_streak && (!is_key_event || (is_tap_hold && record->tap.count == 0) ||
+        achordion_chord(tap_hold_keycode, &tap_hold_record, keycode, record))) {
+      dprintln("Achordion: Plumbing hold press.");
+      settle_as_hold();
+    } else {
+      clear_eager_mods();  // Clear in case eager mods were set.
+
+      dprintln("Achordion: Plumbing tap press.");
+      tap_hold_record.tap.count = 1;  // Revise event as a tap.
+      tap_hold_record.tap.interrupted = true;
+      // Plumb tap press event.
+      recursively_process_record(&tap_hold_record, STATE_TAPPING);
+
+      send_keyboard_report();
+#if TAP_CODE_DELAY > 0
+      wait_ms(TAP_CODE_DELAY);
+#endif  // TAP_CODE_DELAY > 0
+
+      dprintln("Achordion: Plumbing tap release.");
+      tap_hold_record.event.pressed = false;
+      // Plumb tap release event.
+      recursively_process_record(&tap_hold_record, STATE_TAPPING);
+    }
+
+    recursively_process_record(record, achordion_state);  // Re-process event.
+    return false;  // Block the original event.
+  }
+
+#ifdef ACHORDION_STREAK
+  // update idle timer on regular keys event
+  streak_timer = (timer_read() + achordion_streak_timeout(keycode)) | 1;
+#endif
+  return true;
+}
+
+void achordion_task(void) {
+  if (achordion_state == STATE_UNSETTLED &&
+      timer_expired(timer_read(), hold_timer)) {
+    dprintln("Achordion: Timeout. Plumbing hold press.");
+    settle_as_hold();  // Timeout expired, settle the key as held.
+  }
+
+#ifdef ACHORDION_STREAK
+  if (streak_timer && timer_expired(timer_read(), streak_timer)) {
+    streak_timer = 0;  // Expired.
+  }
+#endif
+}
+
+// Returns true if `pos` on the left hand of the keyboard, false if right.
+static bool on_left_hand(keypos_t pos) {
+#ifdef SPLIT_KEYBOARD
+  return pos.row < MATRIX_ROWS / 2;
+#else
+  return (MATRIX_COLS > MATRIX_ROWS) ? pos.col < MATRIX_COLS / 2
+                                     : pos.row < MATRIX_ROWS / 2;
+#endif
+}
+
+bool achordion_opposite_hands(const keyrecord_t* tap_hold_record,
+                              const keyrecord_t* other_record) {
+  return on_left_hand(tap_hold_record->event.key) !=
+         on_left_hand(other_record->event.key);
+}
+
+// By default, use the BILATERAL_COMBINATIONS rule to consider the tap-hold key
+// "held" only when it and the other key are on opposite hands.
+__attribute__((weak)) bool achordion_chord(uint16_t tap_hold_keycode,
+                                           keyrecord_t* tap_hold_record,
+                                           uint16_t other_keycode,
+                                           keyrecord_t* other_record) {
+  return achordion_opposite_hands(tap_hold_record, other_record);
+}
+
+// By default, the timeout is 1000 ms for all keys.
+__attribute__((weak)) uint16_t achordion_timeout(uint16_t tap_hold_keycode) {
+  return 1000;
+}
+
+// By default, Shift and Ctrl mods are eager, and Alt and GUI are not.
+__attribute__((weak)) bool achordion_eager_mod(uint8_t mod) {
+  return (mod & (MOD_LALT | MOD_LGUI)) == 0;
+}
+
+#ifdef ACHORDION_STREAK
+__attribute__((weak)) uint16_t achordion_streak_timeout(uint16_t tap_hold_keycode) {
+  return 100;  // Default of 100 ms.
+}
+#endif
+
+#endif  // version check