diff --git a/2023/grids.clj b/2023/grids.clj
new file mode 100644
index 0000000..a819365
--- /dev/null
+++ b/2023/grids.clj
@@ -0,0 +1,50 @@
+(ns clojure-aoc.grids
+  (:require [clojure-aoc.tools :as tools]))
+
+(def grid-dirs
+  {:up [0 -1]
+   :right [1 0]
+   :down [0 1]
+   :left [-1 0]})
+
+(def opposite-dir
+  {:up :down
+   :left :right
+   :down :up
+   :right :left})
+
+(defn turn [orig dir]
+  (let [index (tools/find-index #(= orig %) (keys grid-dirs))
+        new-index (-> index ((cond
+                               (= dir :none) identity
+                               (= dir :right) inc
+                               (= dir :reverse) #(+ 2 %)
+                               (= dir :left) #(+ 3 %))) (mod 4))]
+    (nth (keys grid-dirs) new-index)))
+
+(defn at [grid [x y]]
+  (nth (nth grid y) x))
+
+(defn rotate-cw [grid]
+  (->> (tools/transpose grid) (map reverse)))
+
+(defn flip [grid]
+  (map reverse grid))
+
+(defn square-partition [size grid]
+  (->> grid
+    (partition size)
+    (map #(->> (tools/transpose %)
+            (partition size)
+            (map tools/transpose)))
+    (apply concat)))
+
+(defn in-bounds [grid [x y]]
+  (and
+    (< -1 y (count grid))
+    (< -1 x (count (nth grid y)))))
+
+(defn neighbours [grid loc]
+  (->> (vals grid-dirs)
+    (map #(map + loc %))
+    (filter #(in-bounds grid %))))
\ No newline at end of file
diff --git a/2023/tools.clj b/2023/tools.clj
new file mode 100644
index 0000000..51bc626
--- /dev/null
+++ b/2023/tools.clj
@@ -0,0 +1,103 @@
+(ns clojure-aoc.tools)
+
+(defmacro debug [coll]
+  `(do (println ~coll) ~coll))
+
+(defn queue
+  ([] (clojure.lang.PersistentQueue/EMPTY))
+  ([coll] (reduce conj clojure.lang.PersistentQueue/EMPTY coll)))
+
+(defn find-index [pred coll]
+  (->> (map-indexed vector coll)
+    (filter #(pred (second %)))
+    first
+    first))
+
+(defn insert-at [coll value index]
+  (let [[l r] (split-at index coll)]
+    (concat l [value] r)))
+
+(defn vec-remove
+  "remove elem in coll"
+  [pos coll]
+  (into (subvec coll 0 pos) (subvec coll (inc pos))))
+
+(defn rotate [coll offset]
+  (let [[l r] (split-at offset coll)]
+    (concat r l)))
+
+(defn swap [coll i j]
+  (let [vec (into (vector) coll)]
+    (-> vec (assoc i (vec j)) (assoc j (vec i)))))
+
+(defn find-cycle [item f hash]
+  (loop [i 1 curr (f item) visited {(hash item) 0}]
+    (let [index (get visited (hash curr))]
+      (if (nil? index)
+        (recur (inc i) (f curr) (assoc visited (hash curr) i))
+        {:offset index
+         :cycle (->> (filter #(>= (second %) index) visited)
+                  (sort-by second <)
+                  (map first))}))))
+
+(defn get-mode [coll]
+  (first (apply (partial max-key second) (seq (frequencies coll)))))
+
+(defn transpose [m] 
+  (apply mapv vector m))
+
+(defn distance [p1 p2]
+  (->> (transpose [p1 p2])
+    (map #(Math/pow (apply - %) 2))
+    (apply +)
+    Math/sqrt))
+
+(defn quad-roots [a b c]
+  (cond
+    (= a b c 0) :all
+    (= a b 0) nil
+    (= a 0) (list (- (/ c b)))
+    :else (let [discrim (-> (Math/pow b 2) (- (* 4 a c)))]
+            (cond
+              (< discrim 0) nil
+              (= discrim 0.0) (list (-> (- b) (/ (* 2 a))))
+              :else (map #(-> (- b) (% (Math/sqrt discrim)) (/ (* 2 a))) [+ -])))))
+
+(defn partition-with
+  [f coll]
+  (lazy-seq
+    (when-let [s (seq coll)]
+      (let [run (cons (first s) (take-while (complement f) (next s)))]
+        (cons run (partition-with f (seq (drop (count run) s))))))))
+
+(defn split-all [pred items]
+  (when (seq items)
+    (apply conj (reduce (fn [[acc curr] x]
+                          (if (pred x)
+                            [(conj acc curr) []]
+                            [acc (conj curr x)]))
+                  [[] []] items))))
+
+(defn split-including [pred items]
+  (when (seq items)
+    (butlast (apply conj (reduce (fn [[acc curr with?] x]
+                                   (if with?
+                                     (if (pred x)
+                                       [acc (conj curr x) true]
+                                       [(conj acc curr) [x] false])
+                                     (if (pred x)
+                                       [(conj acc curr) [x] true]
+                                       [acc (conj curr x) false])
+                                     ))
+                           [[] [] false] items)))))
+
+(defn gcd [a b]
+  (if (zero? b)
+    a
+    (recur b (mod a b))))
+
+(defn lcm_helper [a b]
+  (/ (* a b) (gcd a b)))
+
+(defn lcm [& vals]
+  (reduce lcm_helper vals))