Zip (ZipHQ) Interview Questions
Reconstructed from 46 verified candidate reports across 17 questions. Feb 2025 – Jul 2026.
This page is a live view of every Zip (ZipHQ) interview question AceOffer has indexed — pulled from real candidate reports, not invented from job descriptions or one founder’s memory. Every question shows how many times it’s been reported and when it was last seen. The catalog gets a refresh pass every month.
Key facts
- •17 distinct Zip (ZipHQ) interview questions indexed
- •46 candidate reports across the catalog
- •Most reported: Question/Answer/Condition Matcher (AST Composition Pattern) — 8× (last seen April 2026)
- •Reports span Feb 2025 – Jul 2026
- •Refreshed monthly · last updated July 2026
Browse Zip (ZipHQ) interviews by topic
The Zip (ZipHQ) loop, from candidate reports
Zip (ZipHQ) is a procurement-automation startup, and its loop is unusually front-loaded on the phone screen — reports show candidates rejected there far more often than at the onsite. There are frequently TWO phone screens rather than one: a LeetCode-style round, then a separate practical-coding round where you are dropped into an existing multi-file repository and asked to fill in business logic and write its unit tests. One report notes the practical round was specified as Java by email, so ask which language before you prepare. A self-serve path also exists: a 90-minute online assessment built as four gated levels where each level's tests must fully pass before the next unlocks — the in-memory database and cloud-storage problems in this corpus are both that format, and the reporting candidate cleared three of four and was still rejected. The virtual onsite adds a second coding round, sometimes a system design round focused on service-to-service consistency, and a project deep dive run by a director who expects at least three projects prepared. Reports are consistent that interviewers are friendly and hint readily, and that the binding constraint is time rather than difficulty.
What does Zip (ZipHQ) ask in each interview round?
Zip (ZipHQ) interviews span 5 distinct round types, broken down below. Counts reflect distinct questions per round, not number of times asked. Frequencies on individual question cards show how many candidates reported getting that specific question.
Which Zip (ZipHQ) interview questions come up most?
These are the Zip (ZipHQ)questions reported most across the loops we’ve indexed, sorted by candidate-report frequency.
| Question | Round | Reported | Last seen |
|---|---|---|---|
| Question/Answer/Condition Matcher (AST Composition Pattern) | Coding | 8× | April 2026 |
| Tree Traversal: Find Invalid / Root Nodes | Coding | 6× | November 2025 |
| Poker Card Runs and Sets Enumeration | Coding | 5× | April 2026 |
| Project Deep Dive and Behavioral | Behavioral | 4× | February 2026 |
| Furthest Building You Can Reach (Heap-based / LeetCode 1642) | Phone Screen | 4× | February 2025 |
| House Robber III (Tree DP with Choice Constraint) | Coding | 3× | February 2026 |
| Open the Lock (LeetCode 752) | Phone Screen | 3× | November 2025 |
| Translate/Validate HashMap Values with Nested Support | Phone Screen | 2× | February 2026 |
| BFS Shortest Path with Moving Parade Obstacles | Phone Screen | 2× | July 2026 |
| Max Savings / Phrase Covering Maximum Words with Prefix Tree | Phone Screen | 2× | February 2026 |
The full index is below, or browse the Zip (ZipHQ) catalog →
Every Zip (ZipHQ)interview question we’ve indexed
All 17, grouped by round and sorted by how often candidates reported them. Each links to the question, its reported follow-up count, and when it was last seen.
Coding (6)
- Question/Answer/Condition Matcher (AST Composition Pattern) — reported 8×, last seen April 2026
- Tree Traversal: Find Invalid / Root Nodes — reported 6×, last seen November 2025
- Poker Card Runs and Sets Enumeration — reported 5×, last seen April 2026
- House Robber III (Tree DP with Choice Constraint) — reported 3×, last seen February 2026
- React + Python CRUD Application — reported 1×, last seen September 2025
- LRU Cache: Debugging Challenge — reported 1×, last seen July 2026
Phone Screen (6)
- Furthest Building You Can Reach (Heap-based / LeetCode 1642) — reported 4×, last seen February 2025
- Open the Lock (LeetCode 752) — reported 3×, last seen November 2025
- Translate/Validate HashMap Values with Nested Support — reported 2×, last seen February 2026
- BFS Shortest Path with Moving Parade Obstacles — reported 2×, last seen July 2026
- Max Savings / Phrase Covering Maximum Words with Prefix Tree — reported 2×, last seen February 2026
- Implement Vending Machine (OO Design) — reported 1×, last seen March 2026
OA (2)
- In-Memory Database (4-Level Progressive OA) — reported 1×, last seen July 2025
- Cloud Storage System OOD Design — reported 1×, last seen July 2025
System Design (2)
- Order System Microservice Design — reported 1×, last seen February 2026
- Document Search Platform with Personalization — reported 1×, last seen April 2025
Behavioral (1)
- Project Deep Dive and Behavioral — reported 4×, last seen February 2026
Read two Zip (ZipHQ) questions free
Full problem statements, candidate-reported follow-ups, and walkthroughs. No signup needed.
The most-reported Zip question, and it is not an algorithm round. You are dropped into an existing multi-file form/survey codebase and asked to add a number field supporting three comparisons, test all three, then build a Notion-style filter tree where a condition can contain other conditions. Reports say the interviewer watches specifically for whether the tests cover all three comparisons, and that naming the Composite pattern helps. One candidate ran out of time and still got credit for describing the refactor out loud.
A debugging round rather than an implementation one: you are handed a compiling LRU cache that violates its own spec and asked to find the bug(s), with bonus credit for a failing test per bug. There are two, and the reason this is the free preview is what they do together — eviction removes the most recently used entry instead of the least, while an update never refreshes recency. On the obvious test the two errors cancel and the buggy cache looks correct. Fix only the eviction and a passing case starts failing.
Nodes carry a parent id and a declared level; find the roots and every node whose parent is missing or whose level is a lie, then print the path from each root down to each invalid node. Reports escalate it to multiple disconnected trees and then to many-to-many parents as a discussion. Nothing in any report states whether the root sits at level 0 or level 1 — and the convention flips the answer on every input, so it is the first thing to ask.
- •Asking how many follow-ups a problem has before starting. One report says this explicitly — the coding rounds are staged, and budgeting for the later parts is the difference between finishing and stalling.
- •Reading the repository's structure first in the practical round rather than starting to type. The round tests whether you can find the extension point in someone else's code.
- •Clarifying the scenario before designing. The ML system-design report records the interviewer giving very specific context up front and expecting questions before any design.
- •Explaining your reasoning continuously. One candidate misread the problem, was corrected by the interviewer, pivoted, and still passed — the recovery was visible.
- •Preparing at least three projects for the director deep dive, with size, duration and measurable impact for each rather than technical depth.
- •Running out of time across staged parts. One report finished part 1 slowly because of its follow-ups, got half of part 2 written, and was rejected the next day — concluding both parts must run clean.
- •Losing ten to fifteen minutes to a small bug. Two separate reports attribute a rejection to debugging speed rather than to the approach, which was correct in both.
- •Misreading the prompt at the start. One candidate burned fifteen to twenty minutes before the interviewer pointed out the error.
- •Treating the practical round as reading exercise. The task is to implement AND test; one candidate did not get the implementation written and heard nothing back.
- •In the four-level OA, designing only for the level in front of you. Level 4 asks for the value stored at a past timestamp, and a flat key-value store has to be rewritten to answer it.
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