Microsoft SWE II, Frontend, Oct 2026

Role: Software Engineer, IC3, Frontend-heavy Full Stack, Redmond area Timeline: About 2 weeks from recruiter kickoff to the final round Format: Recruiter call, then a 4-round loop (~60 min each) on HackerRank. The recruiter described it as 2 coding, 1 system/UX design, and 1 hiring manager round. Topics the recruiter listed: TypeScript/JavaScript, React architecture, accessibility, engineering fundamentals, and data-rich seller-facing UIs.

1. Frontend / UX system design (~60 min, whiteboard on HackerRank)

• Design an internal web app where employees view personal financial records (a summary view plus a long, searchable history). Tens of thousands of users, thousands of records each.
• What they asked about:
  • Dashboard layout and what to show "at a glance," and why
  • Table design: columns, search/filter, sort order, drill-down to details
  • React architecture: server cache vs component state vs URL state, and derived vs stored data
  • Client vs server pagination, and virtualization
  • Partial failure: one of two APIs fails for some rows. How do you show it and let the user retry?
  • Accessibility: keyboard flow, screen reader announcements for page-level and row-level errors, labels, toast behavior
• Prep:
  • GreatFrontEnd front-end system design questions ("Design a data table," "Design a news feed")
  • TanStack Query docs on server state
  • WAI-ARIA live regions and the aria-describedby pattern
  • Promise.allSettled for partial failures

2. Project deep dive + coding (~60 min)

• About 20 min on one project you owned end to end. Expect follow-ups on performance (large tables), API contracts with the backend, and the business outcome.
• About 20 min of coding: compute a total using a tiered/progressive rate table (think tax brackets or commission tiers). Tiers are given at runtime.
• Follow-ups covered complexity and how to optimize for repeated queries (precomputing cumulative values per tier, caching).
• Prep:
  • LeetCode 2303 "Calculate Amount Paid in Taxes" (very close in spirit)
  • Prefix sums plus binary search on sorted ranges

3. Coding round 2 (~60 min)

• Standard frontend question, similar to one on greatfrontend.

4. Hiring manager round (ran ~2.5 hrs)

• Background, why you're leaving, why Microsoft, and how your experience maps to the team's domain (trust in financial numbers shown to users).
• Expect coding here too. I was told it would be behavioral and team fit, but it had 2 technical questions:
  • SQL: join a transactions table with a rates table that only has start dates, and total the values per day in one currency. The key is deriving each rate's effective end date with a window function.
  • DP: a minimum-count variant of a classic "make an exact total from given sizes, return -1 if impossible" problem. Watch for integer overflow in your DP array.
• Prep:
  • Essentially don't trust what the recruiter tells you I guess. Cause the Hiring Manager can whimsically act on whatever he wants to do.
  • LeetCode 322 "Coin Change"
  • SQL window functions LEAD()/LAG() with PARTITION BY, plus CTEs
  • DataLemur / LeetCode SQL 50 for "effective date range" joins

Overall

• The design and coding rounds were well structured, on topic, and on time. Interviewers were friendly, and the recruiter was clear and helpful.
• The team is very frontend and UX focused (dashboards for business users, accessibility, large financial datasets). UX thinking and accessibility matter as much as the code.
• Tips:
  • Brush up on SQL and classic DP even for a frontend role. Any round can turn technical - essentially at the discretion of the hiring manager.
  • Think at scale and talk about operational edge cases, not just correctness.
  • Look up your interviewers on LinkedIn, and ask the recruiter for a per-round skill breakdown.