BowTied Fullstack

BowTied Fullstack

Get Hired: Mastering the On-Site Interview Day

Full breakdown of how you can finish the on-site interview day with a juicy offer in hand

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BowTied Fullstack
Feb 18, 2026
∙ Paid

It took a few weeks but you finally made it.

From the first recruiter’s message on LinkedIn, to booking that technical screen, then another.

And now, you’ve arrived. The on-site interview day. In person. Full day.

Here’s what to expect and how to nail it.

Next week, we’ll cover how to close your offer and negotiate exceptions to almost any policy that the job listing and recruiter says is impossible.


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Candidate Stress Test

While there was a brief gap during COVID, on-site interviews have long been the mainstay of the hiring pipeline, especially for big tech roles.

In person, the candidate can’t run, they can’t hide.

You can’t fidget under the table, or get hidden help from Cluely or the latest AI cheating tool.

It’s just you and a whiteboard, or full screen shared laptop.

And it’s not just one interview, you’ll often have 5 or more, usually including a breakdown like this:

  • System Design & Architecture

  • 2 x Pair Programming (Data Structures & Algorithms)

  • Past Experience

  • “Culture Fit” lunch interview

  • Business discussion with CEO or Product Manager

  • “Sell” interview with CTO or Hiring Manager

Let’s briefly go through each.


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System Design & Architecture

Part of the standard interview prep guides, I won’t go super in-depth but you usually are given a task like building a popular platform, but starting at a smaller scale, and then growing it.

For example, build a flight booking platform. Or build Booking.com for hotel rooms but start at the scale of a single boutique Bed & Breakfast. You get the gist.

The key part of this is that the interviewer will drill down further and further to surface how you breakdown a task and identify future bottlenecks in your design.

You’ll usually be talking in front of a whiteboard the whole time as the interview peppers you with follow ups and you madly scribble diagrams on the whiteboard as you talk through your thinking.

Deep dive domains for a standard fullstack engineer role can end up including any of the following:

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