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Akido Software Engineer Interview Guide

Akido Software Engineer interview guide: reported rounds, questions and how candidates describe the process.

The 60-second brief

As a Software Engineer at Akido, you are at the forefront of building technology that drives meaningful impact. Akido is known for its strong culture and deeply mission-driven products, and engineering sits at the very heart of this ecosystem. In this role, you are not just writing code; you are architecting scalable systems that directly improve user experiences and solve complex, real-world problems. The engineering culture here heavily emphasizes adaptability, cross-functional collaboration, and a genuine passion for the products being developed. Your day-to-day impact will span across developing robust backend services, optimizing data pipelines, and ensuring seamless integration with user-facing applications. Software Engineers here are expected to take extreme ownership of their technical domains.

This guide is scoped to a Software Engineer candidate at Akido.

Focus areas

  • Career/Role Alignment
  • Adaptability
  • Requirements Understanding

The Akido interview process

Akido candidates report 3 rounds over 3-5 weeks. The stages below are what candidates describe, not a published process.

Recruiter Screen

Initial conversation with a recruiter to discuss your background, interest in Akido, and high-level technical experiences.

What to demonstrate

  • Initial conversation with a recruiter to discuss your background, interest in Akido, and high-level technical experiences
  • Depth in Career/Role Alignment

How to prepare

  • Be able to walk your CV end to end in two minutes, and say why this company specifically.
  • Have your salary expectations, notice period and location constraints ready, and ask for the rest of the loop in writing.

Technical Phone Screen

A phone interview focusing on core data structures, algorithms, and general coding proficiency.

What to demonstrate

  • A phone interview focusing on core data structures, algorithms, and general coding proficiency
  • Depth in Career/Role Alignment

How to prepare

  • Be able to walk your CV end to end in two minutes, and say why this company specifically.
  • Have your salary expectations, notice period and location constraints ready, and ask for the rest of the loop in writing.

Virtual Onsite Interviews

A series of deep-dive interviews covering advanced coding, system design, and behavioral alignment.

What to demonstrate

  • A series of deep-dive interviews covering advanced coding, system design, and behavioral alignment
  • Depth in Career/Role Alignment

How to prepare

  • Answer aloud and timed: Write an algorithm to group an array of strings into anagrams.
  • Answer aloud and timed: Design a URL shortening service like Bitly. How do you handle high read/write volumes?

Where candidates lose points

Embrace Flexibility

Akido highly values candidates who are adaptable. If an interviewer changes the constraints of a system design question halfway through, roll with it enthusiastically. Show that you view changing requirements as a puzzle to solve, not a frustration.

Focus on the Product

Candidates who express genuine love for the company's culture and products stand out. Take time before your interview to deeply research what Akido builds, and weave that enthusiasm into your behavioral answers.

Always clarify the constraints before writing any code

Interviewers at Akido intentionally leave prompts vague to see if you will ask questions about input size, data types, and edge cases.

Think Out Loud

Silent coding is a red flag. Treat the technical screens as pair-programming sessions. Explain your logic, discuss the time and space complexity of your approach, and ask the interviewer for their thoughts before you optimize.

Questions & practice

Write a function to reverse a linked list in place.

Medium · Coding and Algorithms

Approach

  1. Restate the input: its shape, its size, and what is guaranteed about it.
  2. Name the brute-force solution and its complexity before improving on it.
  3. Choose the data structure from the access pattern, not from familiarity.
  4. State the target complexity and say which constraint rules the naive version out.

Follow-up

  • How does this change if the input no longer fits in memory?
  • What is the worst case, and how likely is it on real data?

Given an array of integers, find the contiguous subarray with the largest sum.

Medium · Coding and Algorithms

Approach

  1. Restate the input: its shape, its size, and what is guaranteed about it.
  2. Name the brute-force solution and its complexity before improving on it.
  3. Choose the data structure from the access pattern, not from familiarity.
  4. State the target complexity and say which constraint rules the naive version out.

Follow-up

  • How does this change if the input no longer fits in memory?
  • What is the worst case, and how likely is it on real data?

Implement a function to check if a binary tree is a valid binary search tree (BST).

Medium · Coding and Algorithms

Approach

  1. Restate the input: its shape, its size, and what is guaranteed about it.
  2. Name the brute-force solution and its complexity before improving on it.
  3. Choose the data structure from the access pattern, not from familiarity.
  4. State the target complexity and say which constraint rules the naive version out.

Follow-up

  • How does this change if the input no longer fits in memory?
  • What is the worst case, and how likely is it on real data?

How would you efficiently find the first non-repeating character in a massive string?

Medium · Coding and Algorithms

Approach

  1. Restate the input: its shape, its size, and what is guaranteed about it.
  2. Name the brute-force solution and its complexity before improving on it.
  3. Choose the data structure from the access pattern, not from familiarity.
  4. State the target complexity and say which constraint rules the naive version out.

Follow-up

  • How does this change if the input no longer fits in memory?
  • What is the worst case, and how likely is it on real data?

Write an algorithm to group an array of strings into anagrams.

Medium · Coding and Algorithms

Approach

  1. Restate the input: its shape, its size, and what is guaranteed about it.
  2. Name the brute-force solution and its complexity before improving on it.
  3. Choose the data structure from the access pattern, not from familiarity.
  4. State the target complexity and say which constraint rules the naive version out.

Follow-up

  • How does this change if the input no longer fits in memory?
  • What is the worst case, and how likely is it on real data?

Explain how you would safely migrate millions of user records from a legacy SQL database to a NoSQL solution w

Medium · System Architecture

Explain how you would safely migrate millions of user records from a legacy SQL database to a NoSQL solution with zero downtime.

Approach

  1. Name the grain you start from and join outward from it.
  2. Check whether any join is one-to-many before aggregating, or the sums inflate.
  3. Say which index the query would use, and what makes it unusable.
  4. Handle the rows that do not match: that is usually the actual question.

Follow-up

  • How does the query change if that join becomes one-to-many?
  • What happens to this when the table is ten times larger?

Explain why the owner filter ignores the listing index

Medium · composite index · query plans · sort elimination

The only index on resource is (tenant_id, status, updated_at DESC, resource_id DESC). A new endpoint returns one user's resources across all statuses, newest created first: WHERE tenant_id = $1 AND owner_user_id = $2 ORDER BY created_at DESC LIMIT 20. On a tenant with 2M rows it takes 900 ms and EXPLAIN shows a sort above a large scan. Explain precisely why the existing index cannot serve it, give the index that can, and state which of these the new index still will not help: owner_user_id alone across tenants; the same query ordered by updated_at. PostgreSQL 16.

Approach

  1. Separate the two jobs an index does. For filtering, a composite btree is seekable only on a left prefix, so with no predicate on status the scan can at best range over tenant_id and test owner_user_id per row; PostgreSQL 16 has no btree skip scan to jump the unconstrained column.
  2. For ordering, the index is sorted by (status, updated_at) within a tenant and not by created_at, so the LIMIT cannot stop early: every matching row is read and then sorted. That is the 'Sort Method: top-N heapsort' line, and it is why the plan reads 2M rows to answer with 20.
  3. Derive the replacement from the access path — equality, equality, then the ordering column: CREATE INDEX CONCURRENTLY ON resource (tenant_id, owner_user_id, created_at DESC). The scan seeks to the (tenant, owner) range and walks 20 entries in order, so the Sort node disappears along with the row-read.
  4. Treat INCLUDE (title, status) as conditional, not free. An index-only scan still visits the heap for any row whose page is not marked all-visible, so on a table taking 1.2k writes/second the win depends on autovacuum keeping the visibility map current, and the wider index costs more on every insert.

Follow-up

  • 90% of rows are status='active'. Would a partial index WHERE status = 'active' change your answer, and for which of the three queries?
  • A dashboard runs this for 40 owners in one page load. What changes about the design?

Architect a leaderboard system for a massive multiplayer platform.

Medium · System Architecture

Approach

  1. Fix the scope first: who calls this, how often, and what they do when it fails.
  2. Name the read and write paths separately; they rarely have the same bottleneck.
  3. Choose a partition key and say what query it makes expensive.
  4. State the consistency you need, and where you are willing to be stale.

Follow-up

  • What breaks first when traffic grows ten times?
  • How does this behave when that dependency is down for an hour?

How would you design a distributed cache system from scratch?

Medium · System Architecture

Approach

  1. Fix the scope first: who calls this, how often, and what they do when it fails.
  2. Name the read and write paths separately; they rarely have the same bottleneck.
  3. Choose a partition key and say what query it makes expensive.
  4. State the consistency you need, and where you are willing to be stale.

Follow-up

  • What breaks first when traffic grows ten times?
  • How does this behave when that dependency is down for an hour?

Design an image upload and processing service that handles various file sizes and formats.

Medium · System Architecture

Approach

  1. Fix the scope first: who calls this, how often, and what they do when it fails.
  2. Name the read and write paths separately; they rarely have the same bottleneck.
  3. Choose a partition key and say what query it makes expensive.
  4. State the consistency you need, and where you are willing to be stale.

Follow-up

  • What breaks first when traffic grows ten times?
  • How does this behave when that dependency is down for an hour?

Listing latency scales with page size, not with filters

Easy · n+1 · latency · query batching

The tenant listing endpoint reads resource filtered by tenant_id and status, ordered by updated_at DESC, and returns each row plus the owner's display name from app_user and the actor of that resource's latest resource_revision. p99 is 55 ms at 10 rows per page and 1.4 s at 200. Database telemetry shows 401 statements per request, each under 1 ms, and nothing in the slow-query log. Diagnose the cause and give the fix, stating the statement count per request and the p99 you expect afterwards.

Approach

  1. Read the counters before forming a theory. 401 statements for 200 rows is one driver query plus two per row, and sub-millisecond execution with an empty slow-query log rules out a bad plan. The time is round trips, which is why it is invisible in every per-query metric and scales with rows returned rather than with filter selectivity.
  2. Name the two per-row statements from their normalised text: a single-row app_user lookup by user_id, and a resource_revision lookup by resource_id ordered by version DESC LIMIT 1. Confirm by dropping those two response fields and watching the statement count fall to one. That locates the calls in the serialisation layer, not the repository.
  3. Check that the arithmetic accounts for the whole gap. Measure one round trip to the replica in isolation; 400 trips at roughly 3 ms of network plus 0.2 ms of execution is about 1.3 s on top of a 55 ms baseline, which matches. If the multiplication had fallen short, the N+1 would only be part of the story and you would keep looking.
  4. Batch both lookups. Collect owner_user_ids and resource_ids from the driver query, then issue WHERE tenant_id = $1 AND user_id = ANY($2) for the users, and PostgreSQL's SELECT DISTINCT ON (resource_id) ... WHERE resource_id = ANY($2) ORDER BY resource_id, version DESC for the latest revision, which the UNIQUE (resource_id, version) index serves directly. On an engine without DISTINCT ON, use a lateral join or a row_number window. Three statements per request at any page size.

Follow-up

  • The page size is capped at 200 today. What breaks first if it is raised to 2,000, and is it still this bug?
  • How do you stop the next N+1 from reaching production, given that no individual query is slow and the endpoint's tests pass?

Suggested practice checklist

Built from the rounds and topics Akido candidates report.

Day 1 — Map the Akido loop

  • Write out the reported sequence: Recruiter Screen, Technical Phone Screen, Virtual Onsite Interviews.
  • For each round, write one sentence on what it is judging, from the description above, and mark the one you are least ready for.

Deliverable: A one-page map of the 3 reported rounds, with the weakest marked.

Day 2 — Work Career/Role Alignment

  • Spend the session on Career/Role Alignment, which Akido candidates report being tested on.
  • Write one worked example in Career/Role Alignment and time yourself on it.

Deliverable: One timed worked example in Career/Role Alignment.

Day 3 — Work Adaptability

  • Spend the session on Adaptability, which Akido candidates report being tested on.
  • Write one worked example in Adaptability and time yourself on it.

Deliverable: One timed worked example in Adaptability.

Day 4 — Work Requirements Understanding

  • Spend the session on Requirements Understanding, which Akido candidates report being tested on.
  • Write one worked example in Requirements Understanding and time yourself on it.

Deliverable: One timed worked example in Requirements Understanding.

Day 5 — Answer out loud: Coding and Algorithms

  • Answer aloud, timed: Write a function to reverse a linked list in place.
  • Answer aloud, timed: Given an array of integers, find the contiguous subarray with the largest sum.

Deliverable: Spoken answers to 2 reported Coding and Algorithms question(s), under time.

Day 6 — Answer out loud: System Architecture

  • Answer aloud, timed: Design a URL shortening service like Bitly. How do you handle high read/write volumes?
  • Answer aloud, timed: Architect a leaderboard system for a massive multiplayer platform.

Deliverable: Spoken answers to 2 reported System Architecture question(s), under time.

Day 7 — Answer out loud: Behavioral and Adaptability

  • Answer aloud, timed: Tell me about a time you applied for one role, but had to pivot to a completely different set of responsibilities.
  • Answer aloud, timed: Describe a time when you had to compromise on technical perfection to meet a strict business deadline.

Deliverable: Spoken answers to 2 reported Behavioral and Adaptability question(s), under time.

Behavioural preparation

Behavioural rounds judge the decision you made and what it cost.

Design a URL shortening service like Bitly. How do you handle high read/write volumes?

Medium · System Architecture

Approach

  1. Pick a story where you made the decision, not one where you watched it.
  2. State the situation in two sentences and spend the rest on the reasoning.
  3. Give the blast radius: what could have broken, and what you measured.
  4. Name the disagreement and how you resolved it with evidence.

Follow-up

  • What would you do differently if you ran that again?
  • How did you know your change caused the improvement?

Tell me about a time you applied for one role, but had to pivot to a completely different set of responsibilit

Medium · Behavioral and Adaptability

Tell me about a time you applied for one role, but had to pivot to a completely different set of responsibilities.

Approach

  1. Pick a story where you made the decision, not one where you watched it.
  2. State the situation in two sentences and spend the rest on the reasoning.
  3. Give the blast radius: what could have broken, and what you measured.
  4. Name the disagreement and how you resolved it with evidence.

Follow-up

  • What would you do differently if you ran that again?
  • How did you know your change caused the improvement?

Describe a time when you had to compromise on technical perfection to meet a strict business deadline.

Medium · Behavioral and Adaptability

Approach

  1. Pick a story where you made the decision, not one where you watched it.
  2. State the situation in two sentences and spend the rest on the reasoning.
  3. Give the blast radius: what could have broken, and what you measured.
  4. Name the disagreement and how you resolved it with evidence.

Follow-up

  • What would you do differently if you ran that again?
  • How did you know your change caused the improvement?

Walk me through a situation where you received highly critical feedback on a code review. How did you handle i

Medium · Behavioral and Adaptability

Walk me through a situation where you received highly critical feedback on a code review. How did you handle it?

Approach

  1. Pick a story where you made the decision, not one where you watched it.
  2. State the situation in two sentences and spend the rest on the reasoning.
  3. Give the blast radius: what could have broken, and what you measured.
  4. Name the disagreement and how you resolved it with evidence.

Follow-up

  • What would you do differently if you ran that again?
  • How did you know your change caused the improvement?

Tell me about a time you were fascinated by a company's product. How did that impact your work?

Medium · Behavioral and Adaptability

Approach

  1. Pick a story where you made the decision, not one where you watched it.
  2. State the situation in two sentences and spend the rest on the reasoning.
  3. Give the blast radius: what could have broken, and what you measured.
  4. Name the disagreement and how you resolved it with evidence.

Follow-up

  • What would you do differently if you ran that again?
  • How did you know your change caused the improvement?

Describe a scenario where you proactively identified a problem outside your immediate scope and fixed it.

Medium · Behavioral and Adaptability

Approach

  1. Pick a story where you made the decision, not one where you watched it.
  2. State the situation in two sentences and spend the rest on the reasoning.
  3. Give the blast radius: what could have broken, and what you measured.
  4. Name the disagreement and how you resolved it with evidence.

Follow-up

  • What would you do differently if you ran that again?
  • How did you know your change caused the improvement?