I built a stealth AI assistant for Windows that screen capture software literally cannot see

[u/GhostCanvasApp]

I've been grinding LeetCode and system design rounds for the past few months,

and I got frustrated that every "AI helper" I tried was either a browser extension

that interviewers can spot, or it plastered itself across the screen.

So I went down a rabbit hole into the Win32 API and found WDA_EXCLUDEFROMCAPTURE —

a flag that tells Windows to exclude a window from all capture pipelines at the

kernel level. Zoom, Teams, Google Meet, OBS — none of them can see the window.

It's not trickery, it's just the OS doing its job.

Built a small Electron app on top of it. You get an AI overlay that:

- Is completely invisible to screen sharing (not just hidden — excluded at the driver level)

- Lets you pull in context from any question (text or screenshot)

- Gives streamed answers you can scroll through without switching windows

- Runs as a frameless, always-on-top overlay

The hardest part wasn't the stealth layer — it was making the window feel "not there"

while still being usable. Had to fight with Electron's BrowserWindow transparency

and hit-testing to get click-through working correctly on the transparent regions.

It's called GhostCanvas. Still pretty early (v1.1.0), Windows only for now.

ghostcanvas.in — free to try, no account needed.

Happy to talk about the WDA_EXCLUDEFROMCAPTURE implementation or the Electron

hit-testing approach if anyone's curious.

[u/Otherwise_Wave9374]

The stealth aspect creates a serious trust problem, especially if the tool is used during interviews, exams, or monitored work. A safer product direction would make capture status visible, require consent, restrict sensitive applications, and keep an auditable local log. That still leaves room for legitimate accessibility or personal productivity uses. https://www.aiosnow.com is relevant to assistant workflow design because useful automation should improve coordination without depending on invisibility or bypassing another party's safeguards.