More Than Just AI

Undetectable AI for interviews with a verified knowledge base

Ask your question by voice or text without ever leaving the live coding window — OfferHack delivers an answer in seconds, powered by a hand-curated knowledge base and the best AI models from leading providers.Voice or text — right from your editor. Verified knowledge base answers in seconds.

Download for macOSApple Silicon

What are the main principles behind EventLoop?

Main Principles of EventLoop

1. Single-threaded JS and Call Stack

The engine has:

Call Stack — this is where your code executes line by line.
Heap — memory for objects (not important for event loop right now).

While there are functions on the stack, JS is busy and cannot do anything else — it cannot handle events or fire timers.

console.log('1');

setTimeout(() => {
  console.log('2 (timeout)');
}, 0);

Try it yourself

⌘+⌥+Z

Voice input

⌘+⌥+⇧

Screenshot

⌃+⌘+⌥

Keyboard capture

Flexible background display settings for any task

Voice input — ask questions hands-free with a single shortcut

Fast responses without long pauses

Send a screenshot via hotkey. AI automatically recognizes the task text.

Hidden input — use the app with mouse and keyboard as usual. Clicking it doesn't take focus away from your active window, like the browser.

Input without interacting with the window — Type into OfferHack via a hotkey, with no extra cursor movement. Convenient during screen sharing: no need to switch between windows or click the app with your mouse.

Main App Features

Trustworthy Answers via RAG

We don't limit ourselves to a small user-supplied context file. OfferHack uses a large knowledge base of hand-curated, verified questions. After a query, the system finds the relevant material and feeds it to the AI. Based on that, the AI composes a more accurate, higher-quality answer.

EvilCorp Code

PureSkillich

KabanKabanich

// Problem C — Minimum Latency Network Routing OfferHack Round 2

// Given n servers, m bidirectional links (latency + bandwidth), and q communicating pairs

// — find routing that minimizes max end-to-end latency.

package main

import ("fmt"; "sort"; "bufio"; "os")

func solve(n, m, q int, edges []Edge, demands []Demand) int {

// Build adjacency list with latency and bandwidth

adj := make([][]Link, n)

for _, e := range edges {

adj[e.u] = append(adj[e.u], Link{e.v, e.w, e.b})

adj[e.v] = append(adj[e.v], Link{e.u, e.w, e.b})

}

// Binary search on maximum allowed latency

lo, hi := 0, 500*1000000

for lo < hi {

mid := (lo + hi) / 2

if feasible(adj, demands, mid) {

hi = mid

} else {

lo = mid + 1

}

return lo

}

What are the main principles behind EventLoop?

Main Principles of EventLoop

1. Single-threaded JS and Call Stack

The engine has:

Call Stack — this is where your code executes line by line.
Heap — memory for objects (not important for event loop right now).

While there are functions on the stack, JS is busy and cannot do anything else — it cannot handle events or fire timers.

console.log('1');

setTimeout(() => {
  console.log('2 (timeout)');
}, 0);

Captured Request

RAG Retrieval

AI Processing

Answer Generating

Seamless Input Without Focus Loss

OfferHack lets you type queries to the AI without losing focus on your active window. Clicking the app doesn't steal focus from your browser, code editor, or any other program. Meanwhile you can use the app as usual: press buttons, select text, enter queries, and drag the window with your mouse.

EvilCorp Code

PureSkillich

KabanKabanich

// Given a string s, find the length of the longest substring without

// duplicate characters. Solve the problem in any way with any complexity

package main

func lengthOfLongestSubstring(s string) int {

maxLen := 0

for i := 0; i < len(s); i++ {

seen := make(map[byte]bool)

for j := i; j < len(s); j++ {

if seen[s[j]] {

break

}

seen[s[j]] = true

if j-i+1 > maxLen {

maxLen = j - i + 1

}

return maxLen

}

What are the main principles behind EventLoop?

Main Principles of EventLoop

1. Single-threaded JS and Call Stack

The engine has:

Call Stack — this is where your code executes line by line.
Heap — memory for objects (not important for event loop right now).

While there are functions on the stack, JS is busy and cannot do anything else — it cannot handle events or fire timers.

console.log('1');

setTimeout(() => {
  console.log('2 (timeout)');
}, 0);

PureSkillich

KabanKabanich

OS-Level Invisibility

The app blends seamlessly into your workspace. Share your desktop freely during an interview while keeping OfferHack right at your fingertips.

ofr-hack-meet12:34 PM

PureSkillich

KabanKabanich

What are the main principles behind EventLoop?

Main Principles of EventLoop

1. Single-threaded JS and Call Stack

The engine has:

Call Stack — this is where your code executes line by line.
Heap — memory for objects (not important for event loop right now).

While there are functions on the stack, JS is busy and cannot do anything else — it cannot handle events or fire timers.

console.log('1');

setTimeout(() => {
  console.log('2 (timeout)');
}, 0);

Other notable features

0:30

Explain how EventLoop handles microtasks and the call stack in Node.js

Transcribed in 0.3sWhisper Large v3 Turbo

Voice Input & Transcription

Say your question or wait for the interviewer's, hit the hotkey, and get an instant transcription with an AI response — completely without manual input. Average transcription time: 0.3–0.6 seconds using Whisper Large v3 Turbo.

⌃+⌘+⌥Keyboard interception

⌘+⌥+⇧Screenshot

⌘+XCapture last 30s audio

Full Hotkey Control

Invisible keystrokesHotkeys are intercepted at OS level — the active app and your interviewer never see the keypress

Keyboard interceptionType directly into OfferHack without switching windows

Screenshot captureSend a screenshot of your screen to AI for analysis

Audio captureRecord and transcribe the last 30 seconds of audio

Hold to TypeHold a modifier key to temporarily intercept keyboard input

Toggle blurInstantly show or hide the app background overlay

Window moveReposition the app window with modifier + arrow keys

Toggle all hotkeysEnable or disable all hotkeys at once

Minimize / Restore windowQuickly hide or bring back the app window

Customizable keyboard shortcuts for maximum efficiency.

What are the main principles behind EventLoop?

Main Principles of EventLoop

1. Single-threaded JS and Call Stack

The engine has:

Call Stack — this is where your code executes line by line.
Heap — memory for objects (not important for event loop right now).

While there are functions on the stack, JS is busy and cannot do anything else — it cannot handle events or fire timers.

console.log('1');

setTimeout(() => {
  console.log('2 (timeout)');
}, 0);

⌃+⌘+⌥Toggle

⌃Hold-to-Type

Input without interacting with the window

With a hotkey, your typing goes straight to OfferHack without taking focus off your live-coding window. Handy during screen sharing: no need to move your mouse or switch between windows unnecessarily.

Google Meet

Zoom

Teams

Discord

OfferHack — hidden from ⌘Tab, screen share, recordings

OS-level invisibility

Make the app completely invisible at the system level.

Settings

Background

Background blur

Tint opacity30%

Tint color

Theme

System

Customizable overlay

Toggle blur, adjust tint, fit your workflow.

~350msavg response

Streaming starts instantly

Lightning-fast responses

Zero-friction, real-time streaming output.

Google

Gemini 2.5 Flash LiteFree
Gemini 3.1 Flash LiteFast
Gemini 3.5 FlashBalanced

OpenAI

GPT-5.4 MiniFast
GPT-5.4Balanced
GPT-5.5Smart

Anthropic

Claude Haiku 4.5Fast
Claude Sonnet 5Balanced
Claude Opus 4.8Smart

xAI

Grok 4.3Fast

Power of choice: top AI models

Switch between the best models right from the interface, without leaving the chat.

System prompt

Standing instructions the assistant follows in every answer.

You are a senior engineer. Answer concisely, with code when useful.

62 / 2000

Answering voice

Choose who the assistant speaks as.

AssistantReplies normally, as an assistant.

First personReplies as if you were speaking — in the first person.

Résumé

Your résumé or key background the assistant can draw on.

0 / 5000

Reference notes

0 / 5

Attach up to 5 .txt or .md files. Drag them anywhere onto this page or click to browse.

Context & notes

Tune how the AI answers you: a system prompt with standing instructions, the response persona (assistant or first-person), response language, your résumé and cover story. Plus attach up to 5 notes in .txt or .md, so answers draw on your own materials.

Works for any interview type

ofr-hack-meet12:34 PM

PureSkillich

KabanKabanich

What are the main principles behind EventLoop?

Main Principles of EventLoop

1. Single-threaded JS and Call Stack

The engine has:

Call Stack — this is where your code executes line by line.
Heap — memory for objects (not important for event loop right now).

While there are functions on the stack, JS is busy and cannot do anything else — it cannot handle events or fire timers.

console.log('1');

setTimeout(() => {
  console.log('2 (timeout)');
}, 0);

Answers any type of theory questions

What are the main principles behind EventLoop?

Main Principles of EventLoop

1. Single-threaded JS and Call Stack

The engine has:

Call Stack — this is where your code executes line by line.
Heap — memory for objects (not important for event loop right now).

While there are functions on the stack, JS is busy and cannot do anything else — it cannot handle events or fire timers.

console.log('1');

setTimeout(() => {
  console.log('2 (timeout)');
}, 0);

Use it during LiveCoding interviews

Works for any tech stack

What are the main principles behind EventLoop?

Main Principles of EventLoop

1. Single-threaded JS and Call Stack

The engine has:

Call Stack — this is where your code executes line by line.
Heap — memory for objects (not important for event loop right now).

While there are functions on the stack, JS is busy and cannot do anything else — it cannot handle events or fire timers.

console.log('1');

setTimeout(() => {
  console.log('2 (timeout)');
}, 0);

Helps with System Design interviews

Choose your plan

Start free, upgrade when you need more

No credit card requiredCancel anytime

First 20 get a free month of subscriptionMessage us on Telegram and we'll gift you a free month of subscription. Check our Telegram for how many spots are left.Message us on Telegram

Free

0 ₽

Perfect for trying things out

Try Free

67 credits per day
Gemini 2.5 Flash Lite model
Screenshot capture
Audio capture
Custom context
RAG-verified answers
Keyboard capture mode

PremiumMost popular

2500 ₽/mo

For a steady job search — one interview per day

Everything in Free
100,000 credits per month
All models available

Ultimate

5000 ₽/mo

For active job hunting — three interviews per day

Everything in Premium
300,000 credits per month

Your subscription renews automatically every month — cancel anytime in your account. You can also see the next charge date there.

Need more credits?

Top up your balance anytime with one-time credit packs — instant, with no change to your subscription.

Unlock credit top-upsCredit packs are available on the Premium and Ultimate plans. Upgrade to top up your balance whenever you need it.

Frequently asked questions

Everything you need to know before getting started

No. OfferHack operates at the OS level as an invisible overlay. It is excluded from screen capture APIs used by Zoom, Google Meet, Microsoft Teams, and other conferencing platforms. Interviewers only see your normal desktop — OfferHack never appears in any screen share, recording, or screenshot.

OfferHack does not inject into other processes, modify browser behavior, or appear in task lists visible to proctoring tools. It runs as a system-level overlay that is architecturally invisible to any screen capture mechanism.

OfferHack captures your system audio and microphone audio, then transcribes it in real time using advanced speech recognition. No browser extensions required — it works with any audio source on your device.

No. When you press an OfferHack hotkey, the keypress is intercepted at the OS level and never reaches the active application. The interviewer sees neither the keystroke nor any reaction from their app. If you bind an OfferHack hotkey that overlaps with a system or app shortcut, OfferHack takes priority — the original command will not fire as long as the hotkey is bound in OfferHack.

Responses typically appear within 2 to 6 seconds depending on the model you select. Smarter models deliver deeper, more detailed analysis, so they may take slightly longer to respond. Faster models are optimized for minimal latency and are well suited for quick hints, clarifications, and simple tasks.

Yes. OfferHack works alongside any application because it operates at the OS level, not as a browser plugin or extension. It's compatible with any video conferencing tool, coding platform, or screen sharing software.

The free plan gives you 67 credits and access to Gemini 2.5 Flash Lite. That's enough to test OfferHack in a real or practice interview before committing to a paid plan. No credit card required.

Yes, no contracts or commitments. You can cancel your subscription at any time before your next billing cycle.