HackTheRounds Interview Experiences

TSMC SRE Interview Experience (2026) - HackerRank OA, Golang Algorithm Round, Offer

TSMC SRE full loop: technical fundamentals with Linux depth checks, 90 minute HackerRank OA (linked list + string compression), 120 minute Golang algorithm roun

By Anonymous ยท 2026-04-03

Background

I was not looking for a move when TSMC's in-house recruiter pinged me about an SRE opening on LinkedIn. Three years of Golang backend at a small analytics company, zero fab-industry experience. The reason I took the loop is that TSMC SRE is one of the few seats where you touch enormous scale problems without being inside a consumer-internet company. What followed: roughly five weeks of staggered rounds.

Timeline

Round 1: Technical Fundamentals (60 min)

The session opened with the hiring manager saying he had already read my resume and did not want an introduction. He jumped straight into what I had picked as my focus area, which for me was Golang plus web backends. The round was structured into four blocks: department scope, process overview, technical Q&A, and my questions.

The technical block hit three categories: core data structures (BST, stack, queue, binary tree, hash map) with exact time complexity and one implementation detail per structure; sorting with follow-ups on when to pick quicksort versus mergesort; and systems-level Linux (HTTP lifecycle, cookies, memory inspection, process management).

The Linux questions were the trap. I could name top , ss , netstat , lsof , but on the kernel primitive behind ss versus netstat I had to say I did not know. He was explicit that the depth check was a signal, not a gate: not knowing was fine as long as I admitted it rather than bluffing. Honesty over bravado showed up again in later rounds.

This question is coming soon to HackTheRounds.

Round 2: HackerRank OA (90 min)

Three problems, 90 minutes, any major language. Difficulty self-assessed as a blend of LeetCode easy and easy-plus. I cleared the first two cleanly and got most of the third. The last problem's edge cases bit me: I failed two hidden tests because my condition check missed an empty-input edge. Final score was a little above the typical 2.5-out-of-3 bar candidates quote.

The coding lanes in my draw were the standard TSMC rotation: one sorting-and-grouping problem (skill-level buckets with a maximum spread constraint), one linked-list construction problem that recursively pulled odd-indexed nodes into a new list, and one string compression problem that felt like a freshman exercise until I realized the edge cases were not forgiving. Sort for the first, careful pointer management for the second, single-pass counter for the third.

Practice it: This question is coming soon to HackTheRounds. The next morning HR called to line up the in-person English and aptitude test plus the Round 3 algorithm interview. The throughput from HackerRank pass to scheduled on-site was under 24 hours, which surprised me after the multi-week silences earlier in the loop.

English + Aptitude Test (on-site

This question is coming soon to HackTheRounds. , 30 min)

The English component was a reading comprehension slog with inconsistent font rendering across chapters. TOEIC background around 750 translated into the company's level-7 band, which I was told is the floor for backend-facing SRE roles. The aptitude portion was standard pattern-recognition and did not feel like a filter.

Round 3: Algorithm & Data Structure Interview (120 min)

Two hours, three LeetCode-style problems, 40 minutes per problem. I used Golang and the Go Playground. Each problem followed the same four-part loop: clarify the prompt, discuss approach and complexity with the interviewer, share screen and implement live, walk through the code line by line afterward.

This question is coming soon to HackTheRounds.

Problem 1: Merge-style List Processing

Problem: Merge a batch of already-sorted input streams into one totally-ordered output stream, where the number of streams can be large and individual streams may be long. Maintain the merged order efficiently.

I froze on this one for the first six minutes. It was the opening problem, I was nervous, and I kept second-guessing whether a min-heap was really the cleanest answer. It was. A min-heap keyed on the head value of each stream, popping the smallest and pushing the next from that stream, runs in O(total log k) for k streams. Once I stopped fighting myself and committed, the code fell out in about eight minutes. The interviewer picked at my use of a custom comparator struct in Go, which was a fair nit, and I acknowledged the readability hit.

Practice it: This question is coming soon to HackTheRounds. Problem 2: Tree Traversal with S

This question is coming soon to HackTheRounds. tate

Problem: Given a binary tree, for each node produce a pointer connection to the next node in the same level from left to right. Constant extra space aside from the tree pointers themselves.

Straightforward once I noticed the constraint disallowed a BFS queue. The level-order pattern collapses into a pointer-walk: use the already-set next pointers at level L to stitch the next pointers at level L+1 . Linear time, constant aux space.

Where I stumbled was a silly one: I dereferenced a nil pointer in my first pass because my sentinel handling was off. The interviewer's feedback afterward called it out explicitly, "you stepped on an invalid memory access at the second problem," which matched my own assessment.

Practice it: This question is coming soon to HackTheRounds. Problem 3: Longest Ordered Subse

This question is coming soon to HackTheRounds. quence

Problem: Given an integer sequence, find the length of the longest strictly increasing subsequence.

Classic. I opened with the O(n^2) DP, confirmed it was accepted for the time budget, then offered the patience-sorting O(n log n) variant as a follow-up. The interviewer seemed to want the simpler solution explained well rather than the fancier one rushed, so I stuck with the DP, coded it in five minutes, and used the last ten minutes to walk through the O(n log n) idea on a whiteboard without implementing it.

Practice it: This question is coming soon to HackTheRounds. Interviewer Feedback

The written

This question is coming soon to HackTheRounds. feedback the manager shared afterward called out three positives (clear algorithmic reasoning, readable Go, comfortable with the language idioms) and two negatives (visible nervousness on Problem 1, the nil-pointer slip on Problem 2). HR turned that feedback into a verbal offer ten business days later.

Result

Offer accepted. Backend SRE team, TSED division. The leveling was what I had targeted and relocation was handled by the company.

Tips

  1. Treat the Round 1 fundamentals as a Linux depth check, not a data-structures check. The data-structures questions are muscle memory if you have interviewed this year. The real signal is whether you can go from "I would use `ss`" to "because `ss` reads from `/proc/net/tcp` and avoids the fd-table walk that `netstat` does." Practice the kernel-side one layer down.
  2. The HackerRank OA edge cases matter more than the algorithms. Every failed candidate I have talked to lost on silent edge cases, not runtime. Before you hit submit, stress your solution against empty input, single-element input, and maximum-range input. TSMC's hidden test set is deliberately boundary-heavy.
  3. For Round 3, commit out loud within two minutes. The interviewer tracks decision latency. If you spend six minutes staring at the first problem like I did, that is recorded. Say the approach you are leaning toward within two minutes even if you are unsure. You can always pivot with better information.
  4. Use Go Playground, not a local IDE, for the live coding round. Sharing a local IDE risks font-size drama and copy-paste etiquette issues. The Playground is clean, shared easily, and the interviewers here know the UI.
  5. Have a crisp answer for "tell me when you struggled technically." The fundamentals round and the HR round both asked a version of this. I used my HackerRank near-miss as the story: what went wrong, what I changed, what I would do differently. Honest beats polished.
  6. Schedule the English test for a morning slot if you can. The reading font rendering is genuinely rough, and eye fatigue compounds over the day. A morning slot got me a cleaner score than I would have managed post-lunch.

TSMC runs its SRE loop slower than the consumer-internet companies, but the individual rounds are tighter than people expect. Prepare for honesty under pressure and for Linux depth one step below the tooling surface, and the loop converts.