Interview Guide

Google Senior Data Engineer Interview (L5)

Hiring for Senior Data Engineer at Google (L5) runs Classic CS fundamentals with a Googleyness round and a hiring committee making the final call. The hiring bar is independent technical leadership and cross-team influence; the median candidate brings 5-8 years of DE experience.

Compensation

$210K–$260K base • $410K–$580K total (L5)

Loop duration

4.8 hours onsite

Rounds

6 rounds

Location

Mountain View, NYC, Seattle, Sunnyvale, Boulder, Dublin

Compensation

Google Senior Data Engineer total comp

Across 198 samples

Offer-report aggregate, 2021-2026. Level mapped: L5. Typical experience: 8-14 years (median 10).

25th percentile

$310K

Median total comp

$342K

75th percentile

$402K

Median base salary

$200K

Median annual equity

$110K

Median total comp by year

2022
$288K n=3
2023
$255K n=6
2024
$332K n=23
2025
$328K n=59
2026
$373K n=99

Tech stack

What Google senior data engineers actually use

Across 13 open roles

These are the tools that show up in Google's senior data engineer DE job descriptions right now. Click any chip to drop into an interview prep page for it.

Warehouse / SQL
BigQuery
Compute
Spark
Cloud
GCP
BI / Viz
Looker
Tableau
Updated from current job listings
Prepare for the interview
01 / Open invite
02min.

Walk into Google knowing the Python pattern they'll test.

a Google Python query, the same shape a screen would give you.
The diff against expected. Where ties broke. What you missed.
sandbox
1def sessionize(events):
2 sessions = []
3 for e in events:
4 if gap_minutes(e) > 30:
5
Execute your solution0.4s avg.
GoogleInterview question
Solve a Google problem

Round focus

Domain concentration by round

Across 13 job descriptions

Where each domain tends to come up in Google's loop, derived from 13 current senior data engineer job descriptions. Longer bars mean heavier weight.

Online Assessment

Python87%
SQL47%
Architecture10%
Spark8%
Modeling6%

Phone Screen

Python67%
SQL65%
Architecture37%
Spark15%
Modeling9%

Onsite Loop

Architecture67%
Modeling30%
SQL29%
Python28%
Spark14%

Practice problems

Google senior data engineer practice set

4 problems

Practice problems tagged with Google, the company each one was written for, at the senior data engineer level where we have them. Click any problem to work it in a live coding environment.

SQLhard~38 min

Competing Standards

For each model (`mdl_name`), find the framework used across the greatest number of its versions, breaking a tie in that count by the higher average accuracy. Sort the resulting model-framework pairs by average accuracy, highest first, and keep every pair whose accuracy places it among the three highest values, including any that share a position.

Open in practice environment→
Pythonmedium~20 min

The Dependency Resolver

You're scheduling pipeline tasks from a dependency map where each task name maps to the tasks that must finish before it runs, and every prerequisite is itself a task in the map. Return an order in which every task comes after all of its prerequisites; if the dependencies form a cycle, no such order exists, so raise an exception instead.

Open in practice environment→
Modelinghard~10 min

The Gaps Between Clicks

We run a consumer web and mobile product that emits a high-volume clickstream: every page view, tap, and scroll lands as an event tied to a device, and a visitor is usually anonymous for a while before they sign in. Analysts need visit-level analysis (how long a session runs, how many events it holds, where it drops off) as well as daily engagement rolled up by page and device, where a session is activity with no more than a thirty-minute gap between consecutive events. Design a model that serves both the visit-level questions and the daily rollups, keeps a person's anonymous and signed-in activity connected, and credits each visit to whoever held the device during the window when that activity happened, since a shared device can pass from one person to another and each of them owns it only for a bounded stretch of time.

Open in practice environment→
Architecturemedium~30 min

A Million Moving Dots

We run a delivery marketplace where every active courier streams a location ping every few seconds, tens of billions of events a day at peak. Customers need a live map and ETA that updates within seconds of each ping, while finance settles courier payouts and merchant fees once a day and cannot tolerate a double-counted or dropped delivery. Design the platform that serves both the live tracking and the exactly-once daily settlement off the same firehose.

Open in practice environment→

Rolling 7-day active users

Count distinct users active in the trailing 7 days for each date. Product analytics staple.

WITH dates AS (
SELECT DISTINCT
activity_date
FROM activity
)
SELECT
d.activity_date AS day,
COUNT(DISTINCT a.user_id) AS rolling_7d_users
FROM dates AS d
JOIN activity AS a
ON a.activity_date <= d.activity_date
AND JULIANDAY(d.activity_date) - JULIANDAY(a.activity_date) < 7
GROUP BY d.activity_date
ORDER BY d.activity_date
Prepare for the interview
03 / Real question02 of many
02hand-picked.

The First of Their Kind

Easy10 min918

When the same record arrives twice, only the first one survives.

Pulled from debriefs where Python parsing was the gate.

The loop

How the interview actually runs

01Recruiter screen

30 min

Level calibration and team matching. Google hires at a level and then matches you to a team post-offer, so the loop is generic even if the recruiter names a specific team.

  • →Be flexible about team. Google teams are assigned after offer
  • →Ask about the 'generalist pool' vs specific-team interview path
  • →Have specific examples of scale: queries per second, petabytes, users served

02Technical phone screen

45 min

Coding problem in a shared doc. DE candidates see SQL + a small algo problem. The algo problem focuses on CS fundamentals, not LeetCode hard.

  • →Practice SQL on Google-scale schemas: ad impressions, search logs, YouTube view events
  • →For the algo portion, arrays/strings/hash maps cover 80%, trees and graphs are rarer for DEs
  • →Explain time/space complexity explicitly

03Onsite: SQL + coding

45 min

2 interviewers, usually split between SQL deep-dive and algorithms. DE loops weight SQL heavier than SWE loops.

  • →Explicit about indexing and query-plan assumptions even though Google uses BigQuery, not indexed databases
  • →Know window functions cold. Google SQL loves them
  • →For algorithms, think out loud about brute force first, then optimize

04Onsite: Data infrastructure design

45 min

Design a large-scale data system. BigQuery, Dataflow, Spanner, Pub/Sub are common prompts. Google loves asking you to design a subset of their own infrastructure.

  • →Know Google's own stack at high level: BigQuery, Dataflow, Spanner, Colossus, Bigtable, Borg
  • →Discuss consistency, partition tolerance, and latency explicitly
  • →Cost and scalability framing land well. Google interviewers think at planet scale

05System design (pipeline architecture)

60 min

Design a production pipeline end-to-end: ingestion, transformation, storage, consumers, SLAs, failure modes, backfill strategy, and cost trade-offs. At senior level, you drive the conversation without prompting. Expect follow-ups about scale, cross-team coordination, and operational load.

  • →Anchor on the SLA and data shape before diagramming
  • →Discuss idempotency, partitioning, and backfill explicitly
  • →Estimate cost: 'This pipeline will cost roughly $X/month at this volume'

06Googleyness + leadership

45 min

Behavioral round assessing collaboration, humility, comfort with ambiguity, and user focus. The hiring committee weights this round heavily.

  • →Googleyness is not a joke, humility and collaborative stories outrank hero-mode stories
  • →Prepare examples of navigating ambiguity and working cross-functionally
  • →Have a user-obsession story, even if your 'user' is another internal team

Level bar

What Google expects at L5 Senior Data Engineer

Independent technical leadership

Senior DEs drive pipeline designs without engineering manager involvement. Interviewers probe whether you can decompose ambiguous requirements, make architecture trade-offs, and defend your choices under scrutiny.

Cross-team coordination

Senior scope regularly spans multiple teams. Expect scenarios about a downstream team missing an SLA because of a change you made, or negotiating a schema migration with the team that owns the upstream source.

Production operational rigor

Fluent in on-call, alerting, data quality checks, and incident response. Dive-deep stories at this level should include correlating a metric drop to a specific commit or a timezone bug or a subtle ordering issue, not 'I looked at the logs.'

Google-specific emphasis

Google's loop is characterized by: Classic CS fundamentals with a Googleyness round and a hiring committee making the final call. Calibrate your preparation to that, generic FAANG prep will not close the gap on company-specific expectations.

Behavioral

How Google frames behavioral rounds

Googleyness

A cultural fit signal for collaboration, humility, and openness. Heavily weighted by the hiring committee.

“Tell me about a time you received critical feedback and acted on it.”

Navigating ambiguity

Google problems are rarely well-specified. They want engineers who can decompose vague goals into concrete milestones without hand-holding.

“Describe a project where the requirements were unclear and you had to define them.”

User focus

Even for internal DE work, Google expects candidates to think about the downstream user (an analyst, a product team, a consumer).

“Tell me about a time a stakeholder's request didn't match their actual need.”

Collaboration across teams

Google scale means every DE project touches multiple teams. Stories about influence without authority score high.

“Describe a situation where you worked with another team that had a different priority than yours.”

Prep timeline

Week-by-week preparation plan

8-10 weeks out
01

Foundations and gap analysis

  • ·Do 10 medium SQL problems. Note which patterns feel slow
  • ·Write out 2-3 behavioral stories per value, Google weights this round heavily
  • ·Read Google's public engineering blog for recent architecture patterns
  • ·Review your prior production work, pick 3-5 projects you can discuss in depth
6 weeks out
02

SQL and coding fluency

  • ·Practice window functions until DENSE_RANK, ROW_NUMBER, LAG, LEAD are reflex
  • ·Do 20+ Google-style problems in their domain
  • ·Time yourself: 25 min per medium, 35 min per hard
  • ·Record yourself narrating your approach aloud. Interviewers weigh how you explain it, not only what you write
4 weeks out
03

Pipeline system design

  • ·Design 5 pipelines on paper: daily aggregation, clickstream, CDC, ML feature store, real-time alerting
  • ·For each, write SLA, partition strategy, backfill plan, and cost estimate
  • ·Practice with a friend, senior-level system design is 50% driving the conversation
  • ·Review Google's open-source and engineering blog for in-house patterns
2 weeks out
04

Behavioral polish and mock loops

  • ·Rehearse every story out loud. Cut to 2-3 minutes each
  • ·Run 2 full mock loops with a senior DE or coach
  • ·Identify your 3 weakest behavioral areas and draft additional stories
  • ·Review recent Google news or earnings call for fresh talking points
Week of
05

Taper and logistics

  • ·No new content. Review your notes only
  • ·Sleep. Mental energy matters more than one more practice problem
  • ·Confirm logistics: laptop charged, shared-doc tool tested, snack and water nearby
  • ·Remember: the loop is rooting for you to raise the bar, not to fail

FAQ

Common questions

What level is Senior Data Engineer at Google?
At Google, Senior Data Engineer corresponds to the L5 level. The bar emphasizes independent technical leadership and cross-team influence without people-management responsibilities.
How much does a Google Senior Data Engineer make?
Looking at 198 sampled offers from 2021-2026, Google Senior Data Engineer total comp comes in at $342K median, ranging from $310K to $402K, median base $200K and median annual equity $110K. Typical experience range: 8-14 years..
How is the Senior Data Engineer loop different from other levels at Google?
The format of the loop matches other levels; difficulty and evaluation shift to independent technical leadership and cross-team influence, and questions at this level dig into independent system design and cross-team influence.
How long should I prepare for the Google Senior Data Engineer interview?
Most working DEs find 8-10 weeks is about right. The technical prep scales with experience; the behavioral story bank is where candidates underestimate time.
Does Google interview data engineers differently than software engineers?
Yes, the DE track at Google emphasizes SQL depth, warehouse and pipeline design, and real production data experience (late data, backfills, quality checks), which generalist SWE loops don't test.