diff --git a/JavaScript/5c-chain.js b/JavaScript/5c-chain.js
new file mode 100644
index 0000000..0a1af28
--- /dev/null
+++ b/JavaScript/5c-chain.js
@@ -0,0 +1,63 @@
+const wrapAsync =
+ (fn) =>
+ (...args) =>
+ setTimeout(() => fn(...args), Math.random() * 1000);
+
+const readConfig = wrapAsync((data, callback) => {
+ console.log("data - ", data);
+ console.log("read config");
+
+ callback(null, data);
+});
+
+const selectFromDb = wrapAsync((query, callback) => {
+ console.log("query - ", query);
+ console.log("select from db");
+
+ callback(null, { cat: "Evgeniy" });
+});
+
+const getHttpPage = wrapAsync((page, callback) => {
+ console.log("page - ", page);
+ console.log("Page retrieved");
+
+ callback(null, { page: "hello world!" });
+});
+
+const chain = () => {
+ const stack = [];
+
+ const executor = () => {
+ let result = () => null;
+
+ const len = stack.length;
+
+ for (let i = len - 1; i >= 0; i--) {
+ const [fn, args] = stack.pop();
+
+ const prev = result;
+
+ result = (err, data) => {
+ if (err) return console.error({ err });
+ fn(...args, prev);
+ };
+ }
+
+ result();
+ };
+
+ executor.do = (cb, ...args) => {
+ stack.push([cb, args]);
+
+ return executor;
+ };
+
+ return executor;
+};
+
+const startChain = chain()
+ .do(readConfig, "myConfig")
+ .do(selectFromDb, "select * from cities")
+ .do(getHttpPage, {});
+
+startChain();
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