IntermediatePROBLEM_SOLVING
You need to design an API endpoint for uploading large files with resume support and minimal server memory usage. Outline your design choices, protocols, and how you ensure data integrity.
Backend Developer
General

Sample Answer

I’d design a chunked upload flow using HTTP/1.1 or HTTP/2 with resumable semantics similar to tus protocol. Clients split files into 5–50MB chunks, POST metadata to create an upload session (ID, size, checksum), then PUT chunks with sequence numbers. The server streams chunks directly to object storage (S3 multipart or GCS compose) to keep memory usage under 5MB per connection. For resume, the server exposes a session endpoint that returns received byte ranges; clients only resend missing chunks. I’d use per-chunk SHA-256 checksums and a final manifest checksum to verify integrity before composing. To protect against partial writes, I’d keep uploads in a staged lifecycle and run a consistency job that reconciles sessions older than 24 hours. This approach cut failed uploads by 90% in a previous project and kept server memory stable under 100MB during peak.

Keywords

Chunked uploads with resumable session IDsStream directly to object storage to minimize RAMPer-chunk and final checksum verificationSession lifecycle and reconciliation for robustness
Related Questions

In your resume you note improving or optimizing [a process, KPI, or metric]. What specific baseline metrics did you start from, what steps did you personally take, and how did you verify that the improvement was due to your changes rather than external factors?

IntermediatePROBLEM_SOLVING

Walk me through a recent multi-channel digital marketing campaign you managed end-to-end. How did you set objectives, choose channels, allocate budget, and measure success?

IntermediateBEHAVIORAL

In your civil engineering studies, what specific design coursework or project work did you complete related to irrigation channels or canals (e.g., design of lined/unlined canals, distributaries, minors)? Describe one such design in detail, including how you determined discharge, permissible velocity, section dimensions, and lining choice for Gujarat-type soil and climate conditions.

IntermediateTECHNICAL

Based on your hydrology and irrigation engineering background, explain how you would estimate the irrigation water requirement for a kharif crop in a semi-arid region of Gujarat. Walk me through each step: from reference evapotranspiration estimation, crop coefficient selection, effective rainfall calculation, to arriving at canal discharge for a given command area.

IntermediateTECHNICAL

On your resume you mention working on a cross-functional project (e.g., involving multiple teams or stakeholders). Describe a situation from that project where priorities conflicted—how did you navigate the trade-offs and what was the final outcome?

IntermediateSITUATIONAL