How is the Zip (ZipHQ) interview structured?

Zip's loop is front-loaded: more of the reported rejections come at the phone screens than at the onsite. There are often two phone screens rather than one: a LeetCode-style round, then a 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. In other loops the practical round sits in the virtual onsite instead. One candidate's invitation required Java, and another asked the recruiter for Python and got it, so ask. Some candidates are sent a 90-minute online assessment built as four gated levels, where each level's tests must fully pass before the next unlocks. The virtual onsite adds an algorithmic coding round and a project deep dive, plus a system design round on some loops: a senior and an ML loop report one, and a mid-level candidate reports none. One director asked for at least three projects prepared.

What coding questions does Zip ask?

The most reported are a practical round inside an existing form codebase, where you add a question type and then build a composite AND/OR filter, and House Robber III on a general tree. Beyond those the set rotates: enumerating card or mahjong melds, a heap-based greedy (LeetCode 1642) with a follow-up asking which resource paid for each step, translating a nested hashmap with a memoised converter and then finding the phrase that saves the most converter calls, Open the Lock, a taxi-grid shortest path with moving parade obstacles, and an LRU cache debugging challenge. In several of them the base problem is quick and the staged follow-ups decide the round.

What is Zip's online assessment like?

90 minutes, four progressively harder levels on a single theme, and each level's tests must fully pass before the next unlocks. The two reports that name a theme describe a simplified in-memory database (CRUD, then filtered display, then TTL expiry, then look-back queries at a past timestamp) and an object-oriented cloud storage system. Three of four was not enough in two reports. One candidate scored 750 out of 1000 and was rejected. Another was told three levels would advance them, finished the fourth with four tests failing, and was rejected two days later.

What question does Zip ask most?

Question/Answer/Condition Matcher (AST Composition Pattern) and House Robber III (Tree DP with Choice Constraint) are tied as the most frequently reported Zip questions in this catalog, at 6 candidate reports each.

How many Zip interview questions does AceOffer cover?

AceOffer covers 14 Zip interview questions reconstructed from verified candidate reports covering Feb 2025 – Jul 2026, with verbatim follow-ups, what passers do, and frequency stats. Zip is included with any AceOffer subscription.

Zip (ZipHQ) Interview Questions

Reconstructed from 41 verified candidate reports across 14 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.

candidate reports

distinct questions

round types

Monthly

refresh cadence

Key facts

•14 distinct Zip (ZipHQ) interview questions indexed
•41 candidate reports across the catalog
•Most reported: Question/Answer/Condition Matcher (AST Composition Pattern) — 6× (last seen April 2026)
•Reports span Feb 2025 – Jul 2026
•Refreshed monthly · last updated July 2026

Browse Zip (ZipHQ) interviews by topic

Coding Interview Questions System Design Interview Questions Interview Process & Rounds

The Zip (ZipHQ) loop, from candidate reports

Zip (ZipHQ) is a procurement-automation startup, and its loop is front-loaded on the phone screen: more of the reported rejections come there than at the onsite. There are often 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. In other loops the practical round sits in the virtual onsite instead. One candidate's invitation specified the practical round in Java, while another asked the recruiter for Python and got it, so ask which language before you prepare. Some candidates are sent a 90-minute online assessment built as four gated levels, where each level's tests must fully pass before the next unlocks. The reported themes were a simplified in-memory database and an object-oriented cloud storage system, and two candidates who cleared three of the four levels were still rejected. The virtual onsite adds an algorithmic coding round and a project deep dive. Some loops also add a system design round, which one senior candidate describes as consistency between two microservices. One director asked for at least three projects prepared. Most reports describe the interviewers as friendly, and several record hints when a candidate stalls, but a hint did not rescue the round in two of those reports. The binding constraint is time more 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.

An algorithmic round — House Robber III on a general tree and card-meld enumeration are both reported here — and in some loops the practical repository round sits here instead of at the phone screen.

5 questions

Most-reported: Question/Answer/Condition Matcher (AST Composition Pattern) (6 reports)

Often two: a LeetCode-style round in staged parts, plus a practical-coding round inside an existing repository.

5 questions

Most-reported: Furthest Building You Can Reach (Heap-based / LeetCode 1642) (4 reports)

Reported twice: consistency between an order service and an inventory service on a senior loop, and an ML document-search platform. One mid-level candidate reports no design round.

2 questions

Most-reported: Document Search Platform with Personalization (1 report)

A project deep dive plus standard motivation questions. One director kept it high level and asked for three projects; another hiring manager spent forty minutes probing one project in detail.

1 question

Most-reported: Project Deep Dive and Behavioral (4 reports)

90 minutes, four gated levels, each unlocking only when its tests fully pass.

1 question

Most-reported: Cloud Storage System OOD Design (1 report)

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	6×	April 2026
House Robber III (Tree DP with Choice Constraint)	Coding	6×	February 2026
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×	September 2025
Open the Lock (LeetCode 752)	Phone Screen	3×	November 2025
Translate/Validate HashMap Values with Nested Support	Phone Screen	3×	February 2026
Max Savings / Phrase Covering Maximum Words with Prefix Tree	Phone Screen	3×	February 2026
BFS Shortest Path with Moving Parade Obstacles	Phone Screen	2×	March 2026
React + Python CRUD Application	Coding	1×	September 2025

The full index is below, or browse the Zip (ZipHQ) catalog →

Every Zip (ZipHQ)interview question we’ve indexed

All 14, 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 (5)

Question/Answer/Condition Matcher (AST Composition Pattern) — reported 6×, last seen April 2026
House Robber III (Tree DP with Choice Constraint) — reported 6×, last seen February 2026
Poker Card Runs and Sets Enumeration — reported 5×, last seen April 2026
React + Python CRUD Application — reported 1×, last seen September 2025
LRU Cache: Debugging Challenge — reported 1×, last seen July 2026

Phone Screen (5)

Furthest Building You Can Reach (Heap-based / LeetCode 1642) — reported 4×, last seen September 2025
Open the Lock (LeetCode 752) — reported 3×, last seen November 2025
Translate/Validate HashMap Values with Nested Support — reported 3×, last seen February 2026
Max Savings / Phrase Covering Maximum Words with Prefix Tree — reported 3×, last seen February 2026
BFS Shortest Path with Moving Parade Obstacles — reported 2×, last seen March 2026

System Design (2)

Document Search Platform with Personalization — reported 1×, last seen April 2025
Order System Microservice Design — reported 1×, last seen February 2026

Behavioral (1)

Project Deep Dive and Behavioral — reported 4×, last seen February 2026

OA (1)

Cloud Storage System OOD Design — reported 1×, last seen July 2025

Read two Zip (ZipHQ) questions free

Full problem statements, candidate-reported follow-ups, and walkthroughs. No signup needed.

Free previewCoding6× reported

Question/Answer/Condition Matcher (Composition Pattern)

Tied for the most-reported Zip question, and it is not an algorithm round. You are dropped into an existing multi-file form codebase, asked to add a number question type and test it, then asked to build a Notion-style filter where one condition can AND or OR other conditions. One candidate advises covering greater-than, equal and less-than in your tests, and reports warn that reading the code and finding where the change belongs takes a real share of the hour. Both parts and their tests are expected. One candidate got the feature working, ran out of time for the refactor, described it out loud instead, and was rejected the next day.

Last reported April 2026Read it →

Free previewCoding1× reported

LRU Cache: Debugging Challenge

A debugging round rather than an implementation one. You are handed a short Java LRU cache, along with its spec and a worked example. The code compiles and looks right but does not meet the spec. Your job is to find the bug(s), and you earn bonus points for a failing test for each one. It is the free preview, so try it cold before you read the walkthrough. In our view, the skill being tested is turning a spec into tests the code has to pass, not scanning for lines that look odd.

Last reported July 2026Read it →

Free previewCoding6× reported

House Robber III (Tree DP with Choice Constraint)

A LeetCode 337 variant, reported at both the technical screen and the onsite. Every node holds a value, and you pick nodes for the largest total without taking a node together with its child. The tree is a general one rather than a binary one: one report says you write the tree yourself, and another got the input as a 2D array. Follow-ups cover complexity, several disconnected trees, and what changes if a node can have more than one parent, which one report describes as a discussion rather than code. Two reports call it easy. One onsite rejection's feedback named debugging by rerunning tests instead of reasoning about the code.

Last reported February 2026Read it →

What passing candidates do

•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. Reports say working out what each file and class does, and finding where the change belongs, takes real time; one puts reading the requirements alone at ten minutes.
•Clarifying the scenario before designing. In the ML system-design report the interviewer gave very specific context up front, and the candidate's advice is to raise anything unclear before starting the 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, impact and your role for each; that report says only one needs full technical detail. Do not count on it staying shallow — another hiring-manager deep dive spent forty minutes probing one project.

Where candidates lose points

•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 time to a small bug. One onsite candidate had the right approach, got stuck on a silly bug for over ten minutes, and suspects that is why they were rejected; another's feedback named debugging by rerunning the code again and again instead of reasoning about it.
•Misreading the prompt at the start. One candidate burned fifteen to twenty minutes before the interviewer pointed out the error; they recovered and passed, getting every test passing only at the 45-minute mark.
•Treating the practical round as a reading exercise. The task is to implement AND test; one candidate did not get the implementation written and heard nothing back.
•Treating three of the four OA levels as enough. One candidate was told three would advance them, left four tests failing on the fourth, and was rejected; another scored 750 out of 1000 and was rejected.

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