diff --git a/2022/04/part1.js b/2022/04/part1.js
new file mode 100644
index 0000000..5c5acd2
--- /dev/null
+++ b/2022/04/part1.js
@@ -0,0 +1,20 @@
+import * as R from "remeda";
+
+import { readFile } from '../03/part1.js';
+
+export const sample = readFile("2022", "04", "sample");
+export const puzzleInput = readFile("2022", "04", "input");
+
+
+const rangeLength = ([a,b]) => b-a+1;
+
+const isContainedBy = ( [a1,a2],[b1,b2] ) =>
+    ( (a1 >= b1) && (a2 <= b2) );
+
+export const solutionPart1 = R.createPipe(
+  (text) => text.split("\n"),
+  R.filter(R.identity),
+  R.map( line => line.split(',').map( range => range.split('-').map( x => parseInt(x) ) ) ),
+  R.map( R.sortBy( x => rangeLength(x) ) ),
+  R.countBy( ([a,b]) => isContainedBy(a,b) )
+);
diff --git a/2022/04/part2.js b/2022/04/part2.js
new file mode 100644
index 0000000..31477e8
--- /dev/null
+++ b/2022/04/part2.js
@@ -0,0 +1,2 @@
+import * as R from "remeda";
+
diff --git a/2022/04/sample b/2022/04/sample
new file mode 100644
index 0000000..9f9e9cf
--- /dev/null
+++ b/2022/04/sample
@@ -0,0 +1,6 @@
+2-4,6-8
+2-3,4-5
+5-7,7-9
+2-8,3-7
+6-6,4-6
+2-6,4-8
diff --git a/2022/04/test.js b/2022/04/test.js
new file mode 100644
index 0000000..9cf5b07
--- /dev/null
+++ b/2022/04/test.js
@@ -0,0 +1,24 @@
+import { test, expect, describe } from "vitest";
+
+import { expectSolution } from "../01/main.js";
+import {
+  solutionPart1,
+  puzzleInput,
+    sample,
+} from "./part1.js";
+import { solutionPart2 } from "./part2.js";
+
+describe("part 1", () => {
+  test("sample", () => {
+    expectSolution(solutionPart1(sample)).toEqual(2);
+  });
+  test("solution", () => {
+    expectSolution(solutionPart1(puzzleInput)).toEqual('TODO');
+  });
+});
+
+describe("part 2", () => {
+  test.todo("solution", () => {
+    expectSolution(solutionPart2(puzzleInput)).toEqual('TODO');
+  });
+});