Arista Networks Software Engineer Interview Guide

We’ve seen Arista care less about flashy algorithms and more about whether candidates can stay precise when the conversation gets practical. Across candidate reports, the recurring pattern is core C/C++ fluency, data structures, and debugging under a fairly barebones setup — CoderPad, SSH, even a nano terminal. That means the bar isn’t just “solve the problem,” but solve it cleanly while handling syntax, memory, and low-level details without much tooling. Multiple candidates also noted that interviewers were calm and helpful, which suggests the company is looking for engineers who can think clearly in a technical back-and-forth, not just grind through a prepared answer.

A second theme is how often Arista pushes beyond surface-level coding into the mechanics behind the code. Our candidates report deep dives on linked lists, BST operations, memory alignment, and Linux/C fundamentals, plus scenario-based networking questions that go all the way from ping and traceroute to DHCP, ARP, and OSPF neighbor states. The non-obvious make-or-break factor here is specificity: one candidate was screened out for not matching the expected language, and others described interviews that felt uneven when they couldn’t keep up with the exact technical framing. In practice, Arista seems to reward engineers who can reason from first principles and explain system behavior concretely, especially when the questions shift from textbook problems to real infrastructure concepts.