OpenAI Backend Engineer interview questions and process

Updated 18 Sep 2026 · 14 sources

Hiring Pulse: where OpenAI candidates are right now

Dated status reports from public Reddit threads and anonymous PortLume reports, updated Oct 18. Not official OpenAI data.

1 status reports in the last 7 days
Not enough data yet: median from final interview to a decision shows at 5+ people
Latest movement: no decisions reported lately

Latest OpenAI hiring reports

Oct 17: OA done Oct 3 (r/csMajors)
Oct 4: OA done Oct 4 (r/csMajors)
Sep 27: OA done Sep 27 (r/csMajors)
Aug 12: Final round Aug 12 (r/cscareerquestions)
Aug 3: Final round Aug 3 (r/csMajors)

Candidates rate the OpenAI Backend Engineer interview Hard: A rejected candidate reported a multi-round loop with a 30-minute presentation, system design under MVP constraints, and a from-scratch database implementation with LSM and tombstone logic. Reports describe 7 rounds, from Recruiter screen to Onsite: coding.

Difficulty: Hard
Skills asked about: System design for scalable backend services, Storage engine and database internals (LSM, tombstones, iterators), Test-driven development

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OpenAI Backend Engineer interview rounds

Recruiter screen: Recruiter screen to confirm role fit and logistics; a 2025 post notes the recruiter described 2 technical rounds plus 1 behavioral for a junior-level backend role.
Technical screening: system design
Technical screening: coding
Onsite: behavioral
Onsite: technical deep dive (presentation + Q&A)
Onsite: system design
Onsite: coding

Questions reported in OpenAI Backend Engineer interviews

Implement a database: add where clause, order by, delete command via tombstone, LSM.
Design a webhook platform: create a webhook request with cxid and JSON blob, URL queried from serviceB, retry for 24 hours.
Define a templatized iterator supporting suspension and resumption, using TDD.
Design Slack: how to deliver an MVP in 2 weeks, and how to handle message delivery scalability and reliability.

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OpenAI Backend Engineer interview: quick answers

How many rounds are in the OpenAI Backend Engineer interview?

Public reports describe 7 rounds for the OpenAI Backend Engineer interview: (1) Recruiter screen, (2) Technical screening: system design, (3) Technical screening: coding, (4) Onsite: behavioral, (5) Onsite: technical deep dive, (6) Onsite: system design, (7) Onsite: coding. Based on 14 public reports, last updated Sep 2026.

Is the OpenAI interview difficult?

Public reports put the OpenAI Backend Engineer interview at Hard difficulty. A rejected candidate reported a multi-round loop with a 30-minute presentation, system design under MVP constraints, and a from-scratch database implementation with LSM and tombstone logic. The process has 7 rounds, from Recruiter screen to Onsite: coding.

Does OpenAI ask DSA in Backend Engineer interviews?

Expect coding, though the reports do not say how DSA-heavy it is. Rounds that involve coding: Technical screening: coding, Onsite: coding. Based on 14 public reports, last updated Sep 2026.

Sources

Based on 14 public reports: YouTube (8), Glassdoor (3), LeetCode Discuss (3), last updated Sep 2026.

Compiled by Adarsh Sharma from public candidate reports. Unofficial guide: PortLume AI is not affiliated with OpenAI.

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