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HubSpot interview notes, page 3 of 3

Large Enterprises

Most of these HubSpot write-ups come from Software Engineers (26), then Product Managers (3) and Machine Learning Engineers (1). The most reported rounds are the system design round (13), the technical phone screen (7), the hiring manager screen (4) and the behavioral / leadership round (3).

30 interview notes · updated Jul 2026

HubSpot·Software Engineer·Onsite - System Design / Architecture

Jun 2026
HubSpot system design round focused on a web crawler problem. The question had a lot of moving parts and the discussion went pretty deep into concurrency and testing, which I wasn't fully expecting for a coding screen.
  • Design a web crawler that starts from a given URL and uses a provided get_links(url) function to discover all pages under the same hostname. It should visit each URL at most once, use a fixed-size worker pool for concurrency, and return the full set of discovered URLs. Walk through your data structures, thread safety approach, and how you'd test it.

“This looked manageable at first.”

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HubSpot·Software Engineer·Onsite - System Design / Architecture

Jun 2026
System design round at HubSpot for a software engineer role. The whole thing was one big design problem about a weather data platform, which sounds deceptively simple but sprawls into a lot of territory fast.
  • Design a weather data platform that pulls hourly data from an external provider for roughly 2,000 U.S. locations and exposes an API returning the current temperature for a given location. Data must never be more than 10 minutes stale relative to the provider's publish time.
  • How would you design the API contract for returning temperature by location, including support for lookup by internal ID and by lat/lon coordinates, plus freshness metadata in the response?
  • Walk through your ingestion pipeline design: how do you detect a new provider publish, handle fan-out across locations, manage retries with backoff, ensure idempotency, and deal with missed hours?
  • What is your caching and invalidation strategy to meet the 10-minute freshness SLA, and how does the API enforce that freshness gate before serving data?
  • How would you scale this system for traffic spikes, and what are your rough estimates for QPS and storage?
  • How would you handle monitoring and alerting on freshness SLOs, upstream failures, and partial outages, and what does graceful degradation look like here?
  • Describe your approach to multi-region availability and disaster recovery for this platform, including RPO and RTO targets.

“This is the whole question, basically.”

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HubSpot·Software Engineer·Onsite - Behavioral / Leadership

Jun 2026
Behavioral round at Hubspot for a software engineering role. Just one question but it had some real teeth to it.
  • Describe a situation where you had buggy code running in production and a rollback wasn't an option. How did you handle it?

“This one tripped me up a bit because most of my war stories involve rollbacks being the first move.”

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HubSpot·Software Engineer·Onsite - System Design / Architecture

Jun 2026
HubSpot system design round for a software engineering role. The prompt was a full banking service implementation, which felt more like a take-home stretched into a live session. A lot to cover in one sitting.
  • Design and implement a minimal banking service that supports account creation with unique IDs and an initial balance, plus deposit and withdrawal operations that prevent overdrafts.
  • How would you design per-account transaction history, including the data structures to store records with timestamps, operation types, amounts, and resulting balances? Also describe APIs to fetch the full history and the most recent N entries.
  • Implement an inter-account transfer system where transfers start in a PENDING state and only execute upon explicit recipient acceptance. Transfers should be canceled if rejected or expired, and the system must handle idempotent accept/reject calls, validate funds at acceptance time, and be safe under concurrent requests.
  • Walk through the time and space complexity of your core operations, and discuss edge cases like duplicate requests, invalid accounts, negative amounts, and clock or timestamp considerations.

“The overdraft piece is where I stumbled a bit.”

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HubSpot·Product Manager·Recruiter / HR Screen

Jun 2026
Short HubSpot PM screen, basically one question about enterprise tools and that was it.
  • What is your favorite enterprise application?

“Felt like a warmup but I still fumbled it a bit.”

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HubSpot·Software Engineer·Technical Phone Screen

Jun 2026
HubSpot technical phone screen for a software engineer role. The whole session was basically one big graph/oracle problem with a bunch of follow-ups stacked on top of each other. Trickier than it looks on the surface.
  • You have n accounts and a black-box API `hasMessaged(a, b)` that tells you if account a has ever sent a message to account b. A spammer is defined as an account that messaged every other account but received messages from nobody. Implement `findSpammer(n)` to return the spammer's index or -1 if none exists.
  • Prove that the elimination phase cannot accidentally discard the true spammer. Why is the verification phase still required after elimination?
  • What is the exact worst-case number of oracle calls, and how do you justify it?
  • How does your solution handle edge cases: n=0, n=1, and self-messages where hasMessaged(i, i) might return true?

“The problem sounds like a celebrity-finding problem in disguise and that framing helped me a lot.”

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HubSpot·Software Engineer·Onsite - System Design / Architecture

Jun 2026
System design round at HubSpot for a software engineer role. The whole thing was built around designing a weather data crawler, which sounds niche but actually covered a lot of ground: scheduling, storage, freshness, retries, the works. Pretty intense for a single session.
  • Design a system that crawls hourly weather data from a public provider like the National Weather Service across 10,000 locations and serves it to internal and external consumers.
  • How would you handle rate limits and flaky responses from the weather data provider?
  • How would you design the storage schema to support both real-time queries and historical analytics?
  • How would you guarantee data freshness and handle backfilling missing or late data?
  • What monitoring and alerting would you put in place to detect missing or delayed data ingestion?

“This is the core question and it's deceptively wide.”

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HubSpot·Product Manager·Hiring Manager Screen

Jun 2026
PM interview at HubSpot, just one question about the company and its market position. Short and a bit awkward if you haven't done your homework.
  • What do you know about HubSpot and where it stands in the market?

“I fumbled a bit here.”

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HubSpot·Software Engineer·Hiring Manager Screen

Jun 2026
Interviewed for a marketing manager role at HubSpot, pretty standard stuff, just one question that I can remember well enough to post about.
  • Why do you want to work at HubSpot?

“Gave my usual answer about inbound marketing and culture but it felt a bit rehearsed coming out of my mouth.”

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HubSpot·Software Engineer·Onsite - System Design / Architecture

Jul 2026
HubSpot system design round for a software engineer role. One question, pretty focused, and it pushed into some edge cases I hadn't fully thought through before sitting down.
  • Design a scheduled payments feature that executes transfers at a specified future time, updates account balances accordingly, and skips the transaction if the source account has insufficient funds at execution time.

“The insufficient funds check tripped me up more than I expected.”

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