diff --git a/codewars/7kyu/simple-fun-204-smallest-integer/koronya.js b/codewars/7kyu/simple-fun-204-smallest-integer/koronya.js
new file mode 100644
index 000000000..bfed3505f
--- /dev/null
+++ b/codewars/7kyu/simple-fun-204-smallest-integer/koronya.js
@@ -0,0 +1,18 @@
+// [JS][7kyu] Simple Fun #204: Smallest Integer
+// simple-fun-204-smallest-integer
+// https://www.codewars.com/kata/58fd96a59a9f65c2e900008d/train/javascript
+
+const smallestInteger = (matrix) => {
+  const arr = matrix.flat()
+  const set = new Set(arr)
+  let i = 0
+  while (set.has(i)) {
+    i += 1
+  }
+  return i
+}
+
+smallestInteger([
+  [0, 2],
+  [5, 1],
+]) === 3