The answer is on your screen.
Not on theirs.
Cloak floats an AI copilot over your live coding interview and solves what it sees, all while staying completely invisible to Zoom, Google Meet, Microsoft Teams, and every screen recorder.
1. Two Sum
Given an array of integers nums and an integer target, return the indices of the two numbers that add up to target.
You may assume exactly one solution exists, and you may not use the same element twice.
Example 1:
Input: nums = [2,7,11,15], target = 9
Output: [0,1]
Constraints:
2 ≤ nums.length ≤ 10⁴
Only one valid answer exists.
Follow-up: can you do better than O(n²)?
One pass with a hash map, trading a little memory for linear time.
Approach
- •We make one pass, storing each number's index in a hash map.
- •For every number we compute the complement, which is target minus the value.
- •If the complement is already in the map, those two indices are the answer.
- •Each lookup is constant time, so the whole scan stays linear.
Complexity
O(n) time, O(n) space: one scan, constant-time lookups.
On your screen. Gone from theirs.
The same coding interview, two views. Cloak solves the problem right in front of you while you share your screen, yet the panel's capture stream never sees it.
You
Daniel · Interviewer
Priya · PanelYouDaniel · InterviewerPriya · PanelStays out of the capture stream entirely, invisible to every tool that records or shares your screen.
Zoom
Google Meet
Microsoft Teams
OBS
A mode for every interview.
Cycle modes live with Right-Option + M. Whatever is on your screen — a coding pad, a whiteboard, an architecture canvas — Cloak reads it and answers in kind.
Requirements
- •Shorten a long URL into a unique short code.
- •Redirect a code back to its original URL.
- •~100M new links/day, read-heavy at 100:1.
API
POST /shorten → { short_url }
GET /{code} → 301 redirect
High-Level Design
System Design. A structured, end-to-end architecture walkthrough with a diagram.
Quiet by design.
Invisible to capture
Screen sharing and recording apps capture everything on your screen, except Cloak. It simply never appears in the stream.
Global hotkeys
Drive everything from the keyboard with Right-Option shortcuts: screenshot, solve, scroll, and hide without ever touching the mouse.
OpenAI
Anthropic
GoogleBring your own keys
Plug in your own OpenAI, Anthropic, or Google keys. They stay on your Mac and never touch our servers.
Non-activating panel
Cloak never steals focus. Your editor stays active and your cursor stays put. The panel just floats above, always ready.
Completely free.
You bring the keys.
Cloak is free forever. Connect your own OpenAI, Anthropic, Google AI keys and you're ready to solve.
OpenAI
sk-4f9A
Anthropic
sk-ant-7c2B
Google AI
AIza9dK1
$0
Forever
No subscription, no trial, no paywall. Cloak is completely free to download and use.
BYOK
Your keys
You bring your own provider API keys. You only ever pay your model provider, never us.
Local
On your Mac
Keys are stored locally on your machine. They never leave your device or hit our servers.
Everything you might ask.
What is an interview copilot?
An interview copilot is an AI assistant that helps you during a live technical interview rather than before it. It reads the problem on your screen, works out an approach, and shows you a solution while the interview is still running. Cloak is an interview copilot for macOS that renders its panel outside the screen-share layer, so the interviewer sees your editor and nothing else.
Is Cloak really invisible during screen sharing?
Yes. Cloak sets its window sharing type to none at the operating-system level, which means macOS excludes it from every capture stream. It never appears in Zoom, Google Meet, Microsoft Teams, OBS, or QuickTime recordings. The app also has no Dock icon and its process runs under a masked name.
Is Cloak free?
Cloak is free forever with no subscription, trial, or paywall. It uses a bring-your-own-key model: you connect your own OpenAI, Anthropic, or Google AI key and pay that provider directly for what you use, which usually amounts to cents per interview. Competing interview copilots charge between $25 and $299 per month.
Which AI models does Cloak support?
Any model you hold an API key for from OpenAI, Anthropic, or Google AI. Because you supply the key, you can switch to a newer frontier model the day it ships instead of waiting for a vendor to add it or gating it behind a higher plan.
Does Cloak work with Zoom, Google Meet, and Microsoft Teams?
Yes. Cloak is invisible to all three, plus OBS, QuickTime, and any other recorder, because the exclusion happens in macOS rather than in the meeting app. It works alongside browser-based coding environments such as CoderPad, HackerRank, and LeetCode, and alongside local editors.
What kinds of interviews does Cloak handle?
Four modes cover the common technical rounds. Solve returns full solutions with multiple approaches and complexity analysis. Whiteboard gives short guiding hints so you keep driving the reasoning. System Design produces a structured architecture walkthrough. Debug pinpoints a bug, rates its severity, and hands you the fix. Cycle modes mid-interview with Right-Option and M.
Do I need to create an account?
No. Cloak requires no account, no email address, and no personal information. Your API keys are stored locally on your Mac and never reach our servers.
What are the system requirements?
macOS 14.2 or later, on either Apple Silicon or Intel. The app is signed and notarized by Apple. On first launch macOS asks for Screen Recording permission, so Cloak can read the question on your screen, and Input Monitoring, so the global hotkeys work.
Is there a Windows version?
Not currently. Cloak is a native Swift application that depends on macOS window-compositing APIs for its invisibility, so there is no Windows or Linux build today.
How is Cloak different from other interview copilots?
Three things. It is free rather than $25 to $299 per month. It is a native Swift app rather than an Electron wrapper or a browser extension, so there is no Dock icon and the process name is masked. And your keys and prompts stay on your machine instead of passing through a vendor's backend.
Slip it on.
Download Cloak and disappear into your next coding interview. Free, forever.
macOS 14.2+ · Apple Silicon & Intel