Build the next-generation Colossus Namespace System (CNS2) — Google's planet-scale distributed file system

Join the CNS2 team building Google's next-generation distributed file system, evolving from CNS1 to deliver a Location Transparent Namespace, cross-cell replication, tiering, and transparent data migration. The role blends hands-on C++ systems work with technical leadership: mentoring engineers and driving architectural direction for foundational storage infrastructure.

Practice this interview

Free · a live voice mock calibrated to this exact role

Start the mock interview

What this interview tests

Distributed file systems / storage infrastructure design
Distributed systems fundamentals (consistency, concurrency, fault tolerance)
Metadata management at scale (Bigtable/Spanner-style systems)
C++ systems programming
Technical leadership and mentorship on ambiguous problems

Common question themes

Design a location-transparent namespace over sharded metadata

Reasoning about consistency/fault tolerance during cross-cell replication or migration

Handling interrupted data migration or stale replica reads

Translating an ambiguous infra requirement into a concrete roadmap

Mentoring engineers and driving architecture decisions as a technical lead

How candidates describe it

Real Software Engineer interview stories — retold from candidates' public write-ups, with sources.

Google · L3 Software EngineerOffer

Google L3 software engineer interview: phone screen, four coding rounds, and the Googleyness round

A candidate with two years of experience went from recruiter outreach to offer over about four months. The onsite was four 45-minute coding rounds — three of them featuring binary trees — and one round turned into a 25-minute chain of follow-ups about approximating an optimal solution at scale.

Interviewed June 2020 · Bangalore, IN

Google · L4 Software EngineerNo offer

Google L4 Software Engineer Interview: Eight Rounds, No Offer

An L4 Software Engineer candidate went through two phone screens, three onsite rounds, a culture conversation, and a team-matching call with a Google hiring manager, then watched the process stall for about a month and a half over a tightened experience requirement before an added extended round ended without an offer.

Interviewed February 2024 · Not specified

Google · L5 Software EngineerNo offer

Google L5 software engineer interview: phone screening, three onsite rounds, system design, and a late rejection

A candidate interviewing for an L5 role went through a phone screening, three onsite coding rounds, a mobile system design round, and a Googleyness and Leadership round. Two of the four technical rounds went poorly by the candidate's own assessment, and after roughly two months of silence the recruiter reported that the role had been closed.

Interviewed January 2023 · Not specified

View the original posting

All Google Software Engineer interviews

All Google interviews