CrackingWalnuts
Checked 3 August 2026. Anthropic describes the tools used and the interview style but publishes no round count, duration or timeline. Everything structural here is commonly reported by candidates. Source: anthropic.com/careers.
| Round | Duration | What it tests |
|---|---|---|
| Phone Screen | 60 min | Practical coding plus background. |
| Take-Home Exercise | 4 to 6 hours | Build a project with safety considerations. |
| Take-Home Discussion | 60 min | Walk through decisions. |
| System Design | 60 min | Claude-flavored system design with safety framing. |
| AI Infra Design | 60 min | Inference, RAG, or eval system. |
| Behavioral / Values | 60 min | Safety-mindedness and judgement. |
| Team Match | 45 min | Final team fit. |
IC4 is the senior level. The bar is "owns features end to end with safety-mindedness, writes well, makes careful technical decisions and can defend them". You are expected to think past the happy path to rollout, failure modes, and what happens when the model is wrong in production.
The loop adds a dedicated AI infra design round and a team match. Safety is woven through system design and behavioral, not isolated to one question.
At this level Anthropic expects misuse, prompt injection from untrusted input, hallucination failure modes, and auditability to be part of the design from the start, not a section bolted on at the end.
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.
Anthropic IC4 (Senior Software Engineer) mixes classical system design with AI-specific design. The AI engineering round is: AI Infra Design (60 min): Inference, RAG, or eval system.. The system design round is: System Design (60 min): Claude-flavored system design with safety framing.. Bar is owning a non-trivial design end to end, with capacity numbers, a clear data model, and one deep dive you can defend under push-back. Prepare in both the AI Engineering track and the System Design Problems track.
Senior bar. The rubric shifts from execution to ownership at scope, judgment, cross-functional impact, and being calibrated on what is hard. Every story needs alternatives considered and what you would do differently. Frame stories around safety-mindedness, mission alignment, and judgment under uncertainty about capabilities.