CrackingWalnuts
Checked 3 August 2026. OpenAI does not publish its interview structure. Everything on this page is commonly reported by candidates, so treat it as a guide rather than a specification.
| Round | Duration | What it tests |
|---|---|---|
| Phone Screen | 60 min | Strategy plus light coding. |
| Practical Coding | 90 min | Build a system in real time. Approach matters. |
| System Design Strategy | 90 min | Multi-year AI infra strategy. |
| AI Infra Deep | 60 min | Inference, RAG, eval pipelines at depth. |
| Cross-Team Leadership | 60 min | How you lead across research and engineering. |
| Behavioral / Taste | 60 min | Engineering judgement at staff scale. |
| Director Round | 45 min | Vision and fit. |
IC5 is the staff level. The bar is "owns multiple systems, drives AI infra strategy across teams, mentors IC4s, and partners with research as a peer".
The loop shifts away from coding toward strategy, infra depth, and leadership. Coding is still present but light. What gets you hired is a specific technical point of view on where the infra should go and evidence you can move multiple teams toward it.
Targeted guidance per round in this loop. Each section links to the matching track on the site. There is no shortcut list, the bar moves loop to loop, so build the pattern recognition and the stories from real practice.
Work the pattern templates until the recognition is instant. Trace one mock problem per pattern. Practice stating time and space complexity out loud before you write code.
At OpenAI IC5 (Staff Engineer), the design portion of the loop is all AI engineering, not classical system design. The round is: AI Infra Deep (60 min): Inference, RAG, eval pipelines at depth.. Bar is owning architectural direction across teams. Trade-offs need numbers, alternatives need names, and the deep dive should be in your strongest area. Prepare in the AI Engineering track, not the System Design Problems track.
Staff bar. The work shifts to cross-team initiative, strategic judgment, influence without authority, and growing other engineers. Behavioral weight is roughly equal to system design at this level. Frame stories around safety-mindedness, mission alignment, and judgment under uncertainty about capabilities.