Machine coding: four timed runs
Four 120-minute rehearsals across weeks 8 to 16, from clarify to code to demo, plus what to record.
Machine coding is LLD with a clock, a running program and a demo at the end. Four runs, weeks 8 to 16, after the designs in the eight designs have given you something to reuse.
Each run is a 120-minute block: 15 minutes to clarify, 90 minutes to code, 15 minutes to demo to camera. The format matches the real round, so rehearse the format and not just the problem.
How to run one
Block 120 minutes, turn the phone off, and record the whole session.
Spend 15 minutes clarifying. Write your questions and assumptions down before you open an editor, because that notebook is part of the score.
Code for 90 minutes. Aim for a skeleton that runs by minute 45, then improve it in place.
Demo for 15 minutes to the camera, interviewer style: the happy path first, then one edge case.
Score the run against the five-check rubric the same day, and file the notes.
The four runs
- In-memory KV with TTL, LRU and concurrent access. This links back to design 8 and proves the design survived contact with code.
- A rate limiter service exposing HTTP, backed by Redis or an in-Go
sync.Map. - A job scheduler with retry and backoff, plus a dead-letter queue.
- A URL shortener API with a rate limit and an analytics counter.
What to record
- The date and which run number it was.
- Your clarify notes, exactly as you wrote them.
- Code duration, and where the 90 minutes actually went.
- The demo video.
- The rubric score and the one fix for next time.
These four artifacts are directly reusable in mock season.
Read once before your first timed run
- Recent Flipkart LLD machine-coding questions and community discussion
- Flipkart interview process guide 2026 for the rounds and sample questions
- Machine coding round guide 2026 (PracHub)