Atlassian Interview Questions — Page 9

Atlassian·Software Engineer·Onsite - System Design / Architecture

Jun 2026

System design round at Atlassian for a software engineer role. The main question was a deep architecture comparison for a music streaming service, which sounds niche but actually covers a lot of ground fast.

For a music streaming service, compare a single-server monolithic deployment against a horizontally distributed multi-host setup. Walk through throughput limits, fault tolerance, global latency, state and data management, deployment complexity, cost scaling, and how you'd migrate between the two. Finish with a recommendation based on listener scale.

“This one sprawled in a way I wasn't ready for.”

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Atlassian·Software Engineer·Onsite - System Design / Architecture

Jun 2026

Atlassian software engineering interview with a system design question focused on OOP for a CI/CD notification service. The problem had enough moving parts to keep you busy for a full session, and the rollover logic is where things get interesting.

Design an object-oriented CI/CD release notification service. Each day deployments run and authors of included commits get notified with their version. If a deployment fails, the system rolls forward to the next version and carries over all pending authors from the failed deployment. Design the core classes (Deployment, Version, Author, Notifier) and the notify() API.

“The rollover logic is what tripped me up at first.”

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Atlassian·Software Engineer·Onsite - System Design / Architecture

Jun 2026

System design round at Atlassian for a software engineer role. The whole thing was one big question about building an async web crawler with a polling API, and it went pretty deep into distributed systems territory.

Design a REST service where clients submit a list of URLs and the service crawls each URL and all its sublinks to extract image references. POST /jobs accepts URLs and returns a job ID; GET /jobs/{id} returns the status and discovered images once complete.

“This one sprawled in every direction.”

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Atlassian·Machine Learning Engineer·Technical Phone Screen

Jun 2026

Atlassian ML Engineer interview with a coding round that included a classic string manipulation problem. Nothing too wild, but it's the kind of question that feels easy until you start second-guessing your cow-counting logic.

Given a secret number and a guess, return a hint string in the format 'xAyB' where x is the count of digits correct in both value and position (bulls), and y is the count of digits that appear in the secret but are in the wrong position (cows).

“The bulls part is easy, just a single pass comparison.”

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Atlassian·Software Engineer·Onsite - System Design / Architecture

Jun 2026

System design round at Atlassian focused on concurrency in a hierarchical org structure. Pretty deep question with a lot of moving parts, felt like they wanted to see how far you could push the design before it fell apart.

Given an organization hierarchy with users and groups, design thread-safe add and remove operations. Walk through your API design, your concurrency strategy, and how you'd avoid deadlocks.
How do you guarantee that reads are consistent while writes are happening concurrently, especially for long-running read queries?
How would you test for concurrency correctness in this system? What does your testing strategy look like?

“This one sprawled way more than I expected.”

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Atlassian·Software Engineer·Onsite - System Design / Architecture

Jun 2026

Atlassian system design round focused entirely on building an authorization system from scratch, combining RBAC and ACL patterns. Pretty deep dive, they wanted the full picture: schema, evaluation logic, APIs, caching, audit logs. Left feeling like I covered maybe 70% of what they were actually looking for.

Design an authorization system that supports both role-based access control (RBAC) and resource-level ACLs, working across multiple resource types like spaces, pages, projects, and issues.
Walk through your permission evaluation algorithm. How do you resolve conflicts between role-based permissions and resource-level ACLs?
What REST APIs would you expose for granting and revoking access, and for checking whether a user is authorized to perform an action?
How would you handle caching for permission checks, and what are the consistency trade-offs when group membership or roles change?
What edge cases would you need to handle, such as deny overrides, permission inheritance across resource hierarchies, and real-time group membership changes?
How would you design the audit logging component for this authorization system?

“I started with the data model because that felt safest, laid out a users/groups/roles table and a separate permissions table linking subjects to resources.”

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Atlassian·Product Manager·Onsite - Product Sense / Strategy

Jun 2026

Atlassian PM interview with a product design question around a weight loss app. Pretty open-ended, which sounds fun until you're actually sitting there trying to figure out where to start.

Design an application that helps users lose weight.

“I spent the first minute just trying to narrow the problem space, which I think was the right call but I probably over-explained my reasoning out loud.”

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Atlassian·Software Engineer·Onsite - Behavioral / Leadership

Jun 2026

Behavioral round at Atlassian for a software engineer role, pretty much one big question about mentorship and knowing when to step in versus back off. Not a lot of technical stuff, just them digging into how you work with people.

Tell me about a time you helped a teammate through a challenge. Walk through what happened, why you got involved, what you actually did, any friction you ran into, and what came out of it. Also: how do you decide when to help versus when to let someone figure it out on their own?

“The last part of this question is what got me.”

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Atlassian·Machine Learning Engineer·Technical Phone Screen

Jun 2026

Atlassian ML Engineer interview had a classic data structures problem that looks deceptively clean on the surface but punishes you if you haven't thought through the bucket approach before.

Design a data structure that supports increment, decrement, get-max-key, and get-min-key operations, all in O(1) average time.

“I knew a hashmap alone wouldn't cut it the moment they said O(1) for both max and min.”

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Atlassian·Software Engineer·Onsite - System Design / Architecture

Jun 2026

System design round at Atlassian for a software engineer role, focused entirely on a notification reliability problem. Pretty deep dive, the kind where you realize halfway through that you've been thinking about it too shallowly.

Your document-signing system is supposed to send notifications after a signature event, but some notifications are silently dropped and nothing shows up in the logs. How do you redesign this to be reliable?
How would you guarantee a notification is persisted before it's ever attempted, so a crash between signing and sending doesn't silently lose it?
How do you make sure retries don't result in duplicate notifications being sent to the user?
What observability would you build around this notification pipeline, and how would you know something is going wrong before users start complaining?
How would you handle documents that were signed but never notified, where the failure happened before anything was even queued?

“This is a bigger question than it looks.”

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