Question 1

Async map limit concurrency

Accepted Answer

**Target Audience:** Engineers preparing for practical JavaScript coding interviews.
**Difficulty:** Medium

> **How to read this doc:** both real requirements — a hard concurrency cap AND preserved result order — were verified together directly, via a real, logged execution trace showing the concurrency never exceeding the limit while the final results array still matched the original input order exactly.

## 1. The problem, restated

`mapLimit(items, limit, mapper)` applies an async `mapper` t

Question 2

Implement a Promise Queue (TaskQueue) with concurrency

Accepted Answer

**Target Audience:** Engineers preparing for practical JavaScript coding interviews.
**Difficulty:** Medium

> **How to read this doc:** the "genuinely inspectable state" claim — the real, defining difference from this bank's own `p-limit` question — was verified directly by reading `running`/`pending` immediately after enqueueing, not just asserted as a design feature.

## 1. The problem, restated

Build a `TaskQueue` class: `new TaskQueue(concurrency)`, an `.add(task)` method returning a promi

Question 3

Implement p-limit — concurrency limiter for async tasks

Accepted Answer

**Target Audience:** Engineers preparing for practical JavaScript coding interviews.
**Difficulty:** Medium

> **How to read this doc:** the "never more than N active at once" claim was verified directly with a real, live execution log across 5 real async tasks at a limit of 2, not just reasoned about.

## 1. The problem, restated

`pLimit(concurrency)` returns a function; wrapping any async task-returning function with it guarantees at most `concurrency` tasks run SIMULTANEOUSLY — additional ta

JAVASCRIPT CODINGDECODED.

Medium

Async map limit concurrency

Implement a Promise Queue (TaskQueue) with concurrency

Implement p-limit — concurrency limiter for async tasks