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FintechProduct company

Block

Builds financial products including Square for sellers, Cash App for consumers, Afterpay and bitcoin related tools.

Not known5 stage process documentedFounded 2009
Headquarters

Oakland, California, United States

Headcount

5,000 and up

5,000 or more people
Work model

Not known

Hiring

Not known

Not enough signal to say. Check the careers page directly.
Where to apply
Careers pageWebsite

Ask for a referral to Block

A referral only means something if the person giving it can actually speak to your work. I will refer you where I know someone on the inside and your profile genuinely fits the role, and I will tell you plainly when I cannot. Either way you get an answer, and a straight one.

  • I read every request. A reply takes a few days, sometimes longer.
  • I will not refer someone for a role their profile does not fit. It wastes your time and costs me the contact.
  • Where I cannot refer you, I will say why, and point you at the way in that does work.
  • Nothing you send here is shared with anyone without you agreeing to it first.

If you found the opening, paste it. It tells me which team you mean.

A Drive, Dropbox or personal-site link is fine. Make sure it opens without a request for access, or I cannot read it.

At least a short paragraph. This is what I would be putting my name behind, so specifics beat adjectives.

Comma separated, up to six. Things you would be happy to be tested on.

How they hire

Block runs hiring through brand career sites such as Square and Cash App. Square states all interviews are virtual. Candidates report that interviewers come from a shared pool rather than the hiring team, and that a small hiring committee reviews the feedback before an offer.

  1. 1

    Recruiter conversation

    Official +1
    Recruiter screen30 minutesRemote

    A first call about your background and interest in the company.

  2. 2

    Technical phone screen

    Reported
    Live coding1 hoursRemote

    A pair programming session on a shared editor, typically a practical problem rather than a puzzle.

  3. 3

    Onsite pair programming rounds

    Official +1
    Live codingRemote

    Square says engineering candidates get a pair programming task. Candidates report two coding sessions in the virtual onsite.

  4. 4

    System design

    Reported
    System design1 hoursRemote

    A high level design session for mid and senior candidates, often with two interviewers.

  5. 5

    Hiring manager and team conversations

    Official +1
    Hiring managerRemote

    Meetings with the hiring manager and cross functional partners about past projects, collaboration and career goals. Senior candidates also get a leadership interview.

What comes up

Recurring themes from candidate accounts, not a question bank. Nobody is served by leaked question lists, least of all you in the interview.

  • Practical coding over puzzles

    Reported

    Problems are framed as small real features, such as splitting a bill between friends, built step by step with the interviewer.

  • Collaboration and past projects

    Official

    Square asks candidates to come ready to talk about specific projects, how they work with others and where they want to go next.

Worth reading before you apply

From the Sefism resource library, matched to the rounds above.

Platform
Design Gurus Problem Set

A browsable practice library of coding problems that can be filtered by pattern, data structure, difficulty and company, so you can drill exactly the weakness you found this week. Patterns include two pointers, sliding window, hash maps, stacks, backtracking and greedy algorithms, with company filters for Google, Meta, Microsoft, Amazon, Oracle and LinkedIn. Free to browse, with an in-browser editor and solutions.

  • Job search
  • DSA
Design Gurus · Interview Prep · Ongoing
FreeDetails
Course
Grokking 75: Top Coding Interview Questions

A course built around 75 coding interview questions chosen for coverage across 18 topic areas, from arrays and sliding window to graphs, backtracking, dynamic programming and tries. Each question has a step-by-step algorithm, a walkthrough and complexity analysis, with solutions in six languages. It suits candidates with a few weeks before an interview who need a balanced, finite problem set rather than an endless list.

  • Job search
  • DSA
Design Gurus · Interview Prep · 3 to 4 weeks · Intermediate
SubscriptionDetails
Roadmap
System Design Interview Playbook

A learning path that bundles five courses into one sequence for system design preparation: System Design Fundamentals, Grokking the System Design Interview, Advanced System Design Interview Volume II, Grokking Microservices Design Patterns and Grokking Design Patterns for Engineers and Managers. Together they add up to 76 chapters and 666 lessons. It suits engineers who want a complete, ordered curriculum instead of assembling one from scattered posts.

  • System design
  • Job search
  • Career
Design Gurus · System Design · 2 to 4 months
SubscriptionDetails
Course
Advanced System Design Interview, Volume II

The second volume of Grokking the System Design Interview, aimed at senior and staff (L5/L6) design rounds. It works through harder case studies such as a payment system, flash sale, notification service, unique ID generator, Gmail, Reddit, Google Calendar and a code judging system, then goes beneath them with patterns like quorum, write-ahead logs and vector clocks and deep dives into Dynamo, Cassandra, Kafka, Chubby, HDFS, GFS and BigTable.

  • System design
  • Backend
  • Job search
Design Gurus · System Design · About 36 hours · Advanced
SubscriptionDetails
Guide
GeeksforGeeks

A very large site of articles on data structures, algorithms and core CS subjects such as operating systems, DBMS, computer networks and OOP, usually with code in several languages, plus practice problems and paid courses. It is handy for revising a university topic or finding a worked example of a specific algorithm. Quality varies because much is community written, so cross-check anything surprising against a textbook or official documentation.

  • DSA
  • CS fundamentals
  • Databases
GeeksforGeeks · Other · Ongoing reference
FreeDetails
Roadmap
Sefism CS Core Subjects Roadmap

An eight-stage roadmap through the core CS subjects: how a computer runs a program, OOP and design, operating systems, computer networks, database theory and internals, software engineering and theory, finished with a systems project such as a shell, an HTTP server or a tiny database. It suits CS students and self-taught developers filling the same gaps, and favours understanding shown in working code over memorised answers.

  • DSA
  • CS fundamentals
  • Databases
Sefism · Other · About 216 hours, 22 to 46 weeks · Beginner
FreeDetails
Browse the whole library

What it pays

Nothing collected for this company yet, and nothing worth guessing at. A made-up range is worse than no range because people negotiate against it.

Add to the Block page

This library is only as good as what people who have been through it are willing to share. Most of these companies have no hiring process documented anywhere, and one account of what the rounds actually were is worth more than anything I can research from the outside.

What are you adding?

This decides how the claim is labelled on the page. Only someone representing the company can produce an “official” label, and I check that separately.

Year and month.

Comma separated topics, not the questions themselves.

Round by round is ideal: what each one was, how long, remote or in person, and what it covered.

Credit

Anonymous is the default. If you keep it anonymous, nothing identifying you reaches the page: it is published as a candidate account and your name stays with me. Never send anything covered by an NDA, and never send a take-home or a question paper.

Universities they recruit from

No sourced university links yet. A campus drive, a career fair appearance or an internship partnership is what puts a university here.

Add to the Block page

This library is only as good as what people who have been through it are willing to share. Most of these companies have no hiring process documented anywhere, and one account of what the rounds actually were is worth more than anything I can research from the outside.

What are you adding?

This decides how the claim is labelled on the page. Only someone representing the company can produce an “official” label, and I check that separately.

Year and month.

Comma separated topics, not the questions themselves.

Round by round is ideal: what each one was, how long, remote or in person, and what it covered.

Credit

Anonymous is the default. If you keep it anonymous, nothing identifying you reaches the page: it is published as a candidate account and your name stays with me. Never send anything covered by an NDA, and never send a take-home or a question paper.

How to actually get seen

Practise pair programming out loud on practical, multi step problems rather than only short algorithm questions. Pick two or three past projects you can discuss in depth, including how you worked with others.

Sources

Whole profile last checked 2026-09-22.

Interviewed at Block? Fill in what changed.

Processes change, rounds get added, tests get replaced. If what you went through was different from what is on this page, tell me and I will update it.

Want me to refer you here?

Send me the role, your CV and a few honest paragraphs on why you fit it. Where I know someone inside and your profile matches, I will make the introduction. Where I cannot, I will tell you why and point you at the route that does work. You get an answer either way.

Ask for a referral to Block

A referral only means something if the person giving it can actually speak to your work. I will refer you where I know someone on the inside and your profile genuinely fits the role, and I will tell you plainly when I cannot. Either way you get an answer, and a straight one.

  • I read every request. A reply takes a few days, sometimes longer.
  • I will not refer someone for a role their profile does not fit. It wastes your time and costs me the contact.
  • Where I cannot refer you, I will say why, and point you at the way in that does work.
  • Nothing you send here is shared with anyone without you agreeing to it first.

If you found the opening, paste it. It tells me which team you mean.

A Drive, Dropbox or personal-site link is fine. Make sure it opens without a request for access, or I cannot read it.

At least a short paragraph. This is what I would be putting my name behind, so specifics beat adjectives.

Comma separated, up to six. Things you would be happy to be tested on.

Add to the Block page

This library is only as good as what people who have been through it are willing to share. Most of these companies have no hiring process documented anywhere, and one account of what the rounds actually were is worth more than anything I can research from the outside.

What are you adding?

This decides how the claim is labelled on the page. Only someone representing the company can produce an “official” label, and I check that separately.

Year and month.

Comma separated topics, not the questions themselves.

Round by round is ideal: what each one was, how long, remote or in person, and what it covered.

Credit

Anonymous is the default. If you keep it anonymous, nothing identifying you reaches the page: it is published as a candidate account and your name stays with me. Never send anything covered by an NDA, and never send a take-home or a question paper.

Work with me

Stuck on something specific?

Writing only gets you so far. If you want an answer to your situation rather than the general case, book a session and we will work through it together. Sessions are free for approved Sefism members, and a few slots open each week.

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