Backstory / context
My application was for a senior software engineer position at HubSpot, and my background is full-stack. The bulk of my work history is shipping production systems with JavaScript, TypeScript, React, Node.js and various cloud services. Early in the process the company asks whether you lean toward a frontend or a backend interview track. I told them backend, and that answer set the shape of every interview I sat through.
How I prepared (what worked and what didn't)
Almost all my preparation time went to the materials HubSpot sent me, and in hindsight that was the smartest thing I did. What I faced in the interviews lined up tightly with what those materials covered, so studying them thoroughly paid off. Alongside that I drilled on narrating how I was thinking, producing tidy code that others can read, and keeping calm when the interviewer kept probing with follow-up questions.
Working through a pile of random LeetCode problems barely moved the needle. These interviews cared far more about fundamentals, sound reasoning and communication than about whether I had memorized patterns.
What the interview process was like
On the backend track, my loop was made up of two system design interviews plus one coding interview. The two design sessions were meant to feel different. In the first, the design was small, and what they wanted was something simple and practical that was easy to follow, with no over-engineering. The second design was larger and pushed me to go deeper on architecture, scaling, tradeoffs and how the system stays maintainable over the long run.
The coding interview was about solving the problem and explaining it well. The interviewers followed up repeatedly to see how I dealt with edge cases and with extending the solution.
After those went well, a frontend opening came up right then, so one more interview was added, this one about JavaScript. Anyone who picks the frontend track at the start would have this round built in. It leaned heavily on language fundamentals, such as prototypes, what this refers to in different contexts, and how core JavaScript behaves, and it did not test framework knowledge.
Any surprises
What stood out was how well organized and even-handed everything felt. There were no gotcha questions, and what I had been told beforehand matched what actually happened. Being able to change tracks depending on what the team needed was something I never expected, and I appreciated it.
Advice for other candidates
- Decide honestly whether frontend or backend suits you better, then prepare for the areas that track puts weight on.
- Go through the materials they send you and make sure you really absorb them, because they closely mirror what the interviews are like.
- Rehearse narrating your reasoning as you work. How you communicate gets weighed about as much as the answer you land on.
- For system design, get comfortable with a repeatable way of walking through a design, and study a few worked examples in depth.
- Before a JavaScript round, shore up the basics, especially
this, prototypes and how the language itself behaves.
Final thoughts
All in all, the process was considerate of my time and checked actual engineering ability rather than trivia. Prepare carefully, know the fundamentals cold and speak clearly about what you are doing, and a HubSpot interview should go well for you.
Discussion
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