Company guides
🟦 Dropbox — Frontend Interview Guide
Emphasis: File UIs, sync/offline, large-data handling, and uploads. Rendering huge file trees and resumable uploads are on-brand.
Related: Company index · ROADMAP
The loop (typical)
| Round | Focus | Prep section |
|---|---|---|
| Phone screen | JS/DSA | 03-javascript |
| Coding | UI component / machine coding | 16-machine-coding |
| Frontend system design | File/sync "Design X" | 15-system-design |
| Behavioral | Collaboration | — |
What they emphasize
- File UIs — trees, explorers, large lists (virtualization).
- Upload flows — chunked, resumable, progress, retries.
- Sync & offline — conflict handling, optimistic updates.
- Large-data performance.
Frequently asked (community-sourced)
Machine coding
- Build a File Explorer / Tree View → nested comments pattern
- Build a chunked/resumable File Upload → pattern
- Build a Data Grid (file list) → flagship
- Build a Virtualized List → flagship
System design
- Design Dropbox / a file browser → 15-system-design
- Design a File Upload system → pattern
- Design offline sync → flagship
Patterns
- Offline-first, sync, optimistic UI → 17-patterns · 13-state
Prep plan (2 weeks)
- Build a file tree + virtualization.
- Implement a chunked/resumable upload with progress + retries.
- Study offline/sync patterns.
- Practice a file-browser system design.
🟢 Green flags · 🔴 Red flags
🟢 Do: render large file trees with virtualization · build chunked/resumable uploads with progress + retry · handle sync/offline and conflicts. 🔴 Avoid: rendering huge trees fully · uploads with no progress/retry · ignoring conflict resolution.
📝 Sample interviewer prompts
- "Build a file explorer tree view."
- "Build a resumable file upload with a progress bar."
- "Design offline sync for a file browser."
Interviewed at Dropbox? Add the questions you got (role + year) via a PR.