Documentation
Everything you need to know to use Blind.Codes effectively during your coding interviews.
Quick start
Download and open the app. Sign in with GitHub.
Grant Screen Recording permission when prompted (macOS only).
Position the overlay window on your screen. It stays on top of everything.
When a coding problem appears on screen, press ⌘ ⇧ S. The solution appears in seconds.
Installation — macOS
Download the DMG for your Mac architecture (Apple Silicon or Intel), open it, and drag Blind.Codes to your Applications folder.
On first launch, macOS will ask for Screen Recording permission. Go to System Settings → Privacy & Security → Screen Recording and enable Blind.Codes.
Installation — Windows
Download the .exe installer, run it, and follow the setup wizard. Blind.Codes will install and launch automatically.
No additional permissions are required on Windows. The app captures your screen directly without a system prompt.
First use
After signing in, you get 5 free credits — no credit card required. Each credit = one AI analysis.
The app window is invisible to screen recordings and screenshots by default. Your interviewer cannot see it.
App shortcuts — macOS
These shortcuts work globally — even when the app is not focused.
| Capture screen & analyze | ⌘ ⇧ S |
| Stealth mode (mouse passes through) | ⌘ ⇧ L |
| Hide / show the window | ⌘ ⇧ H |
| Reset opacity to default | ⌘ ⇧ O |
| Reset to home position | ⌘ ⇧ X |
App shortcuts — Windows
Same shortcuts as macOS but using Ctrl instead of ⌘.
| Capture screen & analyze | Ctrl Shift S |
| Stealth mode (mouse passes through) | Ctrl Shift L |
| Hide / show the window | Ctrl Shift H |
| Reset opacity to default | Ctrl Shift O |
| Reset to home position | Ctrl Shift X |
System shortcuts
These standard shortcuts also work inside the app window.
| Zoom in (increase text size) | ⌘ + / Ctrl + |
| Zoom out (decrease text size) | ⌘ - / Ctrl - |
| Quit the app | ⌘ Q / Alt F4 |
Language selector
Use the dropdown in the top bar to force a specific language. By default it's set to Auto — the AI detects the language from the problem context.
Supported languages: Python, JavaScript, TypeScript, Java, C++, C, C#, Go, Rust, Swift, Kotlin, Ruby, PHP, SQL.
Opacity & visibility
Open Settings (⚙️) to adjust:
- ◈ Opacity — base transparency of the window
- ◈ Hover opacity — transparency when your mouse is over the window
- ◈ Hover effect — toggle whether hovering changes opacity
- ◈ Width / Height — resize the window to fit your screen layout
Press ⌘ ⇧ O at any time to reset opacity to default.
Free credits
Every new account gets 5 free credits on first login. Credits never expire.
Buying credits
Open Settings (⚙️) → Buy credits. Choose a pack and you'll be redirected to a secure Stripe checkout.
| Starter | 20 credits | $5 |
| Standard | 40 credits | $10 |
| Pro | 110 credits | $25 |
Credits are added to your account instantly after payment. No subscription — pay once, use anytime.
Promo codes
Open Settings (⚙️) → enter your promo code in the field at the bottom → click Apply. Credits are added immediately.
⚡ Simulation mode
Use it before your interview to get comfortable with the workflow: positioning the window, adjusting opacity, and triggering the shortcut without hesitation.
How to enable it
Open Settings by clicking ⚙️ in the top bar.
Toggle Simulation mode on. A SIM badge appears in the top bar to confirm it's active.
Press ⌘ ⇧ S as usual. A sample solution appears instantly — no credit used.
Toggle it off before your real interview. The SIM badge disappears.
Tips & tricks
Stay stealth
Blind.Codes is built to be undetectable. Here's how to make the most of it.
Screen recording detection
The overlay is content-protected at the OS level — excluded from all screen capture APIs on both macOS and Windows. Your interviewer's recording will never show the window, even if it's fully visible on your screen.
Process enumeration detection
Some interview platforms (CoderPad, HackerRank, Codility, etc.) scan the list of running processes to detect suspicious apps. Blind.Codes runs as a background accessory process with no Dock icon and no taskbar entry — it has a minimal system footprint and does not appear as a typical user-facing application in the process list.
Focus detection
The overlay never steals focus from your browser or editor. Clicking the window, triggering a capture, or showing the window after hiding it — none of these will cause your interview tab to lose focus.
Stealth mode
Enable Stealth mode with ⌘ ⇧ L (or Ctrl Shift L on Windows). When active:
- ◈ Your mouse passes through the window — clicks go to the browser or editor behind it
- ◈ The interview tab never loses focus, even when you trigger a capture
- ◈ A Stealth indicator appears in the top bar
This is the most important feature. Without Stealth mode, clicking the window or triggering a capture could steal focus from your interview browser — the interviewer might notice you switching windows.
Best practices
✓ Dry run checklist
Do this before every interview
Run through these steps in your interview browser to make sure everything works and nothing gets flagged. Takes under 2 minutes.
Step 1 — Enable Simulation mode
Open Settings ⚙️ and toggle Simulation mode on. The SIM badge appears in the top bar. This lets you test the full workflow without spending any credits.
Step 2 — Enable Stealth mode
Press ⌘ ⇧ L (or Ctrl Shift L on Windows) to activate Stealth mode. The Stealth indicator appears in the top bar.
With Stealth mode on, your mouse passes through the overlay and your interview browser never loses focus — even when you trigger a capture.
Step 3 — Test your shortcuts
With both modes active, practice the full sequence:
Press ⌘ ⇧ S — a sample solution should appear in the overlay instantly.
Press ⌘ ⇧ H — the overlay hides. Press again — it reappears.
Press ⌘ ⇧ O — opacity resets to default.
Step 4 — Run the Stealth Benchmark
Open blindcodes.github.io/stealth-benchmark in your interview browser and click Run all checks. It simulates the detection techniques used by platforms like CoderPad, HackerRank, and Codility.
While the benchmark is running, press ⌘ ⇧ S to trigger a capture — the shortcut should appear in the event log. Aim for a score of 100%.
FAQ
Is the app visible to the interviewer?
No. The window is content-protected and hidden from screen recordings and screenshots on both macOS and Windows.
Do credits expire?
No. Credits never expire and are tied to your account, not your device.
Can I use the app on multiple computers?
Yes. Sign in with the same GitHub account on any Mac or Windows PC and your credits will be there.
What happens if the AI doesn't recognize the problem?
The app will display "No coding problem identified on the screen". A credit is still used since the AI processed the screenshot.
The app says "Screen Recording permission required" (macOS)
Go to System Settings → Privacy & Security → Screen Recording → enable Blind.Codes. Then restart the app.
Windows SmartScreen blocks the app
Click More info → Run anyway. The warning appears because the app is not yet code-signed, not because it's malicious.
I paid but my credits didn't update
Credits are added automatically after payment. If they don't appear within a minute, close and reopen the app. Contact support@blind.codes if the issue persists.