Invisible Interview Tool

How Screen Sharing Detection Works

Interview platforms use several methods to detect unauthorized assistance. Understanding these is important for evaluating whether an interview tool is actually undetectable or just claims to be.

• DOM scanning — Platforms like HackerRank and CodeSignal inspect the page for injected elements, modified styles, and unfamiliar script tags. Any browser extension that adds visible elements can be found this way.
• Extension enumeration — Some platforms query the browser's extension APIs to list installed extensions. Known interview-assistance extensions get flagged immediately.
• Tab focus tracking — Switching away from the interview tab triggers a detection event. Platforms log how many times you leave the tab and for how long.
• Clipboard monitoring — Pasting large blocks of code that appeared in no prior keystrokes raises flags in proctored environments.
• Screen recording review — Some companies review the full screen recording after the interview. Any visible overlay, second window, or suspicious tab switch shows up here.

Why Browser Extensions Get Caught

Browser-based interview helpers inject HTML, CSS, and JavaScript into the interview platform's page. This creates multiple detection surfaces:

The injected elements exist in the same DOM tree that the platform controls. A single MutationObserver can detect any new element that wasn't created by the platform's own code. Even if the extension adds elements to a shadow DOM or an iframe, the container itself is detectable.

Network requests from browser extensions use different request patterns than normal page behavior. Platforms can fingerprint these by monitoring the fetch/XHR timeline. And because extensions run in the browser process, they appear in the screen share — if the interviewer looks at a screen recording, any visible overlay from an extension will be there.

How macOS Content Protection Works

Phantom Coder uses a macOS feature called window-level content protection. When an application sets its window sharing type to CGWindowSharingType.none, the operating system excludes that window from all screen capture APIs — CGWindowListCopyWindowInfo, SCShareableContent, and the legacy CGDisplayStream.

This is the same mechanism used by streaming apps (Netflix, Disney+) to prevent screen recording of copyrighted content, and by banking apps to protect sensitive data. It operates at the WindowServer level, below any application code. Screen sharing software — Zoom, Google Meet, Microsoft Teams, WebEx — receives a composited frame from the OS that simply does not include the protected window.

This is fundamentally different from a CSS trick or a transparent overlay. The window is not "hidden" by making it see-through — it is excluded from the capture pipeline by the operating system itself. There is no application-level workaround for the screen-sharing software to see through this because it never receives the pixel data.

Beyond the Overlay

Screen protection is only one layer. Phantom Coder also eliminates every other trace of its presence:

• Hidden from dock — No icon appears in the macOS dock, so a shared screen showing the dock reveals nothing
• Hidden from Activity Monitor — The process does not appear under its real name in Activity Monitor or the Force Quit dialog
• Hidden from Mission Control — Swiping up to show all windows does not reveal the Phantom Coder overlay
• Click-through mode — The overlay passes mouse clicks through to the window beneath it, so your cursor behavior looks normal
• No browser footprint — Nothing is installed in Chrome, Firefox, or Safari. No extension to enumerate, no injected scripts, no modified DOM.

Works Across All Platforms

Because the invisibility is at the OS level, Phantom Coder works with every screen sharing and interview platform — Zoom, Google Meet, Microsoft Teams, WebEx, Discord, Slack huddles, and any other application that uses macOS screen capture APIs. It also works with every coding platform: LeetCode, HackerRank, CoderPad, CodeSignal, or a plain text editor.

$99/month or $499 for lifetime access. 40 credits per day — Flash queries and audio transcriptions cost 1 credit, Pro queries cost 5. Multiple AI models, custom system prompts. Requires macOS 13+.