Your interview prep,
packed into a desktop OS.
PrepOS is a calm, focused launchpad for software engineering interviews. Daily DSA, dev news, focus tracker, AI chat, lockdown mode, and every prep platform — all running side-by-side in a familiar macOS-style shell.
- Solve PoTD
- Mock interview 4 PM
- Review system design notes
One desktop. Every prep tool.
Zero context switches.
Tabs, notebooks, half-finished problems, three Notion docs — sound familiar? PrepOS collapses your prep stack into a single OS-style shell so you stop juggling and start shipping.
Focus tracker
Pomodoro-style sessions tied to any prep app. Hard-lock mode blocks Cmd+Q until your session ends — useful for the 4 AM grind.
Problem of the day
Curated DSA rotation across topics — arrays, DP, graphs, system design. One click opens it inside the in-app browser.
AI chat with vision
Cmd+Shift+A captures any region of your screen and pipes it into GPT-4o or Claude 3.5 Sonnet — perfect for stuck-on-a-problem moments.
Dev news, in one place
Hacker News, Dev.to, GitHub Trending, freeCodeCamp, ByteByteGo, plus India interview-prep staples (GfG, Striver, NeetCode, InterviewBit). One calm reader, no infinite scroll trap.
Modes for every season
Pick a persona on first launch — college student or working pro — and PrepOS pre-loads a matching dock, feed pack, and focus goal. Switch modes (Placement Sprint, System Design Week, Internship Hunt) in one keystroke.
Lockdown mode
When deadlines loom, lockdown locks the OS shell — no app switching, kiosk mode, no distractions. Unlock with an explicit confirm dialog.
Streaks + tasks
Daily streak counter and a quick-add task list right on the desktop. Plan the day in 30 seconds, glance at progress all day.
Notes + Monaco playground
Markdown notes (with capture attach) and a built-in Monaco editor for rapid 'try this snippet' moments — no leaving the app.
Plug-in any platform
Add LeetCode, GFG, HackerRank, Excalidraw, anything — they run as sandboxed webviews inside PrepOS with persistent logins.
One-time OS warning. Here's how to bypass.
PrepOS ships without paid Apple notarization or Windows EV signing — so your OS will warn you on first launch. The app is fully open-source, you can read every line on GitHub. Follow the steps below once, and the OS remembers your choice forever.
macOS — Gatekeeper
“Apple cannot check it for malicious software.”
- 1Don't run PrepOS from the DMG. Open the DMG and drag PrepOS.app onto the /Applications shortcut next to it, then eject the DMG.Launching straight from the mounted disk image triggers a repeat warning every time. Copying to /Applications is a one-time step.
- 2Double-click
/Applications/PrepOS.app. If macOS asks “Are you sure you want to open it?” click Open — this is a one-time confirmation. - 3If macOS blocks it instead(“Apple cannot check it for malicious software” with no Open Anyway button), strip the quarantine flag in Terminal:Works on every macOS version including Sequoia 15+, where Apple removed the Open Anyway button for unsigned apps. Double-click afterwards — Gatekeeper stays quiet from here on.
xattr -dr com.apple.quarantine /Applications/PrepOS.app - 4Older macOS only: right-click
PrepOS.app→ Open and confirm in the dialog, or visit System Settings → Privacy & Security → Open Anyway. On Sequoia these are hidden — use the Terminal fix above.
Windows — SmartScreen
“Windows protected your PC.”
- 1Click More info in the blue dialog → Run anyway.
- 2If silently blocked, right-click the installer → Properties → check Unblock → OK.
- 3Run the installer again. SmartScreen remembers from now on.
Linux — AppImage
One step, then run forever.
- 1Right-click the AppImage → Properties → Permissions → check Allow executing as program.
- 2Or via terminal:
chmod +x PrepOS-*.AppImage ./PrepOS-*.AppImage - 3On first launch it auto-integrates into your launcher / dock.
Prefer to build from source? Run npm install && npm run dev from the repo root — full instructions in the README.