Interview Intelligence
Technical Interview Prep — Coding, System Design, and Technical Screens
Most candidates prepare the wrong things in the wrong order. This guide covers the full technical interview loop — coding rounds, system design, behavioral in technical contexts, and how to calibrate your prep to your target level.
- Coding interview strategy — what to practice and in what order
- System design framework — the 7-step approach
- Behavioral rounds in technical loops
- Senior vs. Staff level calibration
- Study plan template by timeline
- The most common technical interview mistakes
The 6 components of technical interview prep
Technical interview preparation is not just LeetCode. A full prep plan covers six distinct components — and most candidates neglect at least two of them.
- Coding fundamentals: Arrays, strings, trees, graphs, dynamic programming, sorting. 150–200 problems minimum.
- System design: Practice 8–10 canonical designs using a consistent framework. The patterns generalize.
- Behavioral prep: 6–8 STAR stories covering technical decisions, cross-functional influence, and execution under pressure.
- Company research: Understand the tech stack, architecture decisions, and engineering culture before your loop.
- Role calibration: Staff-level system design differs substantially from senior-level. Know what level you are being evaluated at.
- Mock practice: At least 3 full mock interviews before your real loop — timed, spoken, with feedback.
The most expensive technical interview mistake
Silent coding. Most candidates code in silence during technical screens — they treat the interview like an exam where you work quietly and submit an answer. Interviewers evaluate your thinking process, not just your solution.
Talking through your approach, stating your assumptions, surfacing the tradeoffs you see, and explaining why you chose one approach over another is often weighted as heavily as whether the code compiles. Candidates who communicate clearly while solving consistently outperform better coders who stay silent.
Practice speaking while coding from day one of your prep — not as an afterthought before your interview.
System design — the 7-step framework
Use the same structure for every design question. The patterns transfer across problems.
Ask about functional and non-functional requirements before drawing anything. What does the system need to do? What does it not need to do? What are the latency and availability targets?
Number of users, requests per second (read vs. write), data volume, storage requirements. Rough math is enough — the goal is to identify whether you need sharding, caching, or CDN from the start.
What entities exist? What are the relationships? What is read-heavy vs. write-heavy? This drives your storage and indexing decisions downstream.
Define the core endpoints or interfaces before designing internal architecture. This grounds the design in concrete behavior.
Clients, load balancers, application servers, databases, caches, queues. Get the skeleton down before diving into any component.
Pick the most interesting or most complex piece and go deep — data model, indexing strategy, consistency tradeoffs. Interviewers often guide this, but offer to drive it yourself.
What fails under load? Where are the single points of failure? What would you change if consistency mattered more than availability? Proactively surfacing tradeoffs signals Staff-level thinking.
Senior-level technical interviews
Senior engineer loops evaluate whether you can solve problems correctly, communicate your approach clearly, and demonstrate competence with standard data structures and algorithms.
Coding: Medium to hard LeetCode difficulty. Expected to recognize patterns, walk through time and space complexity, and handle edge cases without prompting.
System design: High-level design of a moderately complex system. Expected to use standard components correctly — load balancers, databases, caches — and discuss one or two tradeoffs.
Behavioral: Individual contribution, execution, technical decisions. Expected to own outcomes with clear "I" language and quantified results.
Staff-level technical interviews
Staff engineer loops evaluate whether you can operate at organizational scope — designing systems that serve millions of users, influencing architectural direction, and navigating technical ambiguity without a clear problem statement.
Coding: Often less emphasis, but expected to be fluent. The bar shifts toward architectural judgment.
System design: Design at scale with real tradeoffs. Expected to drive the conversation, propose the framework, and proactively surface failure modes and edge cases.
Behavioral: Cross-team influence, mentorship, technical strategy, and organizational impact. "I" stories must show scope beyond your immediate team.
Study plan by timeline
4–6 weeks (Senior SWE loop)
- Weeks 1–2: Coding fundamentals — arrays, strings, hashmaps, two pointers, sliding window, binary search. 10–15 problems per day.
- Weeks 2–3: Trees, graphs (BFS/DFS), recursion, backtracking. Continue daily reps.
- Weeks 3–4: Dynamic programming, heaps, advanced patterns. Start timed problem sets.
- Week 4–5: System design — 2 designs per week with the 7-step framework. URL shortener, notification system, rate limiter, news feed, distributed cache.
- Week 5–6: Mock interviews (minimum 3). Behavioral story bank. Company-specific research.
8–12 weeks (Staff / Principal loop)
- Weeks 1–3: Algorithm fundamentals refresh. Do not skip even if you feel comfortable — Staff loops occasionally include hard coding.
- Weeks 3–6: System design at scale — 3 designs per week. Design for 100M+ users. Focus on tradeoffs, not just components.
- Weeks 6–8: Behavioral story development. Map stories to Staff-level dimensions: cross-team influence, organizational impact, technical strategy, ambiguity navigation.
- Weeks 8–10: Company-specific deep research — engineering blog, tech talks, architecture decisions. Understand what this company has built.
- Weeks 10–12: Mock loops (minimum 4). Calibrate Staff-level signal in system design and behavioral rounds specifically.
Prepare for your technical loop with someone who has been on the hiring side
Askia's technical interview coaching builds your coding strategy, runs calibrated system design mock sessions, and gives specific feedback on whether your answers land at the right level. 89% of coached clients land offers in 60 days.
