Convert markdownlint library to an ECMAScript module, replace markdownlint-micromark with micromark, stop publishing (large) markdownlint-browser.js, see https://gist.github.com/sindresorhus/a39789f98801d908bbc7ff3ecc99d99c for guidance.

example/gulpfile.cjs

@@ -0,0 +1,24 @@
+// @ts-check
+
+"use strict";
+
+const gulp = require("gulp");
+const through2 = require("through2");
+
+// Simple task wrapper
+gulp.task("markdownlint", function task() {
+  return gulp.src("*.md", { "read": false })
+    .pipe(through2.obj(function obj(file, enc, next) {
+      import("markdownlint").then(({ "default": markdownlint }) => {
+        markdownlint(
+          { "files": [ file.relative ] },
+          function callback(err, result) {
+            const resultString = (result || "").toString();
+            if (resultString) {
+              console.log(resultString);
+            }
+            next(err, file);
+          });
+      }).catch(next);
+    }));
+});