Coding, Algorithms, and Debugging
We assess correctness, clarity, efficiency, and robustness. Interviews often blend LeetCode easy–medium, targeted bitwise/pointer work, and deliberate debugging. For systems roles, you may code in C/C++ and discuss memory access patterns and cache behavior.
Be ready to go over:
- Core data structures: arrays, strings, linked lists, stacks/queues, hash maps, trees/graphs, heaps
- Algorithmic techniques: two pointers, sliding window, BFS/DFS, topological sort, DP basics
- Complexity & validation: time/space tradeoffs, edge-case testing, input fuzzing
- Advanced concepts (less common): lock-free patterns, memory alignment, SIMD-friendly layouts
Example questions or scenarios:
- “Implement an LRU cache and explain eviction complexity and concurrency options.”
- “Find the longest palindromic substring; compare expand-around-center vs. DP.”
- “Merge two sorted linked lists; then extend to K lists and justify heap complexity.”
- “Given code with a subtle memory leak and shallow copy, identify and fix the lifetime bugs.”
Systems, OS, and Performance Engineering
Many roles demand deep Linux and systems intuition: how things run, break, and get tuned. Expect to reason about threads/processes, synchronization, scheduling, paging, NUMA, I/O, and profiling under realistic load.
Be ready to go over:
- OS internals: processes vs. threads, context switching, virtual memory, page tables, caching/TLB
- Concurrency: locks, atomics, deadlocks, lock contention, false sharing, producer–consumer
- Performance tooling: perf, gdb, valgrind, flame graphs, cachegrind; reading traces/logs
- Advanced concepts (less common): eBPF, kernel bypass I/O, NIC offloads, zero-copy
Example questions or scenarios:
- “Explain a segmentation fault caused by use-after-free; show how you’d find it.”
- “Profile a CPU-bound service that regressed after a change; propose measurement and mitigation.”
- “Design a thread-safe queue; discuss memory ordering guarantees and scalability limits.”
System Design and Architecture
Design interviews emphasize clarity, tradeoffs, and performance realism. Many teams favor API design, high-performance services, or GPU-aware architecture over purely web microservices patterns.
Be ready to go over:
- API design & contracts: versioning, idempotency, pagination, error semantics
- Throughput/latency tradeoffs: batching, caching, compression, vectorization
- Reliability & observability: fault domains, graceful degradation, SLOs, tracing
- Advanced concepts (less common): GPU-centric pipelines, kernel fusion, zero-copy paths
Example questions or scenarios:
- “Design a rate limiter with per-tenant quotas; discuss distributed state and hot keys.”
- “Sketch an inference serving platform for LLMs (vLLM/TensorRT), covering batching, KV cache, and autoscaling.”
- “Evolve an API to support streaming results; discuss backpressure and memory bounds.”
Domain Depth by Team
Interviewers probe your ability to apply fundamentals to their domain. Preparation should match the job family.
Be ready to go over:
- GPU/CUDA/Compilers: memory hierarchy, warp scheduling, occupancy, kernel fusion, MLIR/LLVM basics
- Networking & Linux kernel: EVPN/VXLAN, SR-IOV, RDMA/RoCE, Cumulus/SwitchDev, packet pipelines
- Robotics/AV: real-time scheduling, ROS/ROS2, QNX/Linux, C++ optimization, perception/control loops
- HW–SW co-design (VLSI/Verification): STA (setup/hold), CDC, FSMs, basic Verilog/UVM concepts
- Advanced concepts (less common): vLLM/MLPerf, NCCL/NVSHMEM, TensorRT-LLM, CUDA-Q
Example questions or scenarios:
- “Diagnose low GPU occupancy in a kernel; propose shared memory and tiling improvements.”
- “Translate control-plane to data-plane constructs in a switch pipeline; discuss ACL/QoS offloads.”
- “Build a tool to scan a Verilog file for leaf modules; explain parsing approach and edge cases.”
Behavioral, Ownership, and Collaboration
We evaluate how you lead, communicate, and learn.
Be ready to go over:
- Ownership: incidents you led, cross-team delivery, hard tradeoffs you made
- Intellectual honesty: how you surfaced unknowns and corrected course
- Mentorship & influence: leveling up peers, unblocking teams, driving standards
- Advanced concepts (less common): stakeholder negotiation under hardware and schedule constraints
Example questions or scenarios:
- “Describe a time you found a critical performance flaw late in the cycle—what did you do?”
- “Tell us about mentoring a junior engineer through a complex code path and its impact.”
