Senior Engineer: 4-Month FAANG Prep Plan
Target: Staff Engineer / L5–L6 (senior; potential principal track)
Timeline: 16 weeks, ~12 hours/week (you're busy; this is surgical)
Outcome: Ready for 2–3 FAANG loops; negotiating principal offers
Overview
| Phase | Weeks | Focus | Goal |
|---|---|---|---|
| Calibration | 1–3 | Understand senior bar; refresh on medium-hard DSA | Know what you're preparing for |
| Depth & Leadership | 4–11 | Principal-level designs + strategic thinking | Ready for senior/staff interviews |
| Application & Loop | 12–16 | Focused applications + real onsites | Principal offer in hand |
PHASE 1: CALIBRATION (Weeks 1–3)
Mindset: Senior interviews are NOT harder DSA; they're about judgment, strategy, and impact.
Time commitment: 10 hours/week
Week 1: Self-Assessment
| Day | Activity | Output |
|---|---|---|
| Mon | Review senior bar for your company | Notes on expectations |
| Tue | Read 3 senior-level system design interviews (Palantir, Jane Street, etc.) | Understand the depth required |
| Wed | Record yourself designing a system (untimed); compare vs. junior approach | Identify gaps |
| Thu–Fri | Skim DSA hard problems; time yourself on 3 (LeetCode) | Ensure speed (< 20 min each) |
| Sat–Sun | Light: read career progression docs | Calibrate expectations |
Output: Clear picture of senior bar; confidence in existing skills.
Week 2–3: DSA Maintenance + Signal
Goal: You can code fast; prove you think big.
| Day | Activity | Format | Time |
|---|---|---|---|
| Mon–Wed | 3 hard problems per day; aim for < 20 min (with explanation) | LeetCode | 60 min/day |
| Thu | Record coding session; focus on explaining your approach | Self-record | 45 min |
| Fri | Mock coding interview 1 (60 min; hard problem) | Peer-led | 90 min |
| Sat | Debrief; identify communication gaps (not correctness gaps) | Self-study | 30 min |
| Sun | Rest | Rest | Rest |
Weeks 2–3 parallel: Read 2–3 architecture blogs (AWS Well-Architected, Google SRE Book excerpts).
Output: Fast problem solving + clear explanation; DSA not a bottleneck.
PHASE 2: DEPTH & LEADERSHIP (Weeks 4–11)
Mindset: At senior level, interviews test your judgment, not your speed. Take your time. Think aloud.
Time commitment: 12 hours/week
Week 4–6: Strategic System Design (I)
Goal: Design systems that matter; discuss tradeoffs like a principal engineer.
| Day | Activity | Problem | Notes |
|---|---|---|---|
| Mon | Study: capacity planning | Numbers precision | Get numbers exactly right |
| Tue | Study: patterns & failure handling | Theory depth | Understand why patterns matter |
| Wed | Design: URL Shortener, BUT add: analytics, real-time dashboard, ML recommendations | Deep design | Think 3 years out |
| Thu | Design: News Feed; focus on ranking system (ML + data infrastructure) | Data pipeline | Show data thinking |
| Fri | Mock Design 1 (90 min; novel prompt) | Peer-led | Rubric: Expect 4.5/5+ |
| Sat | Debrief; ask peer: "What would a principal engineer do differently?" | Mentorship | Incorporate feedback |
| Sun | Rest | Rest | Recharge |
Weeks 5–6: Repeat with:
- Rate limiter (add: fairness across users, dynamic adjustment)
- Chat system (add: encryption, compliance, geo-distribution)
- Video streaming (add: bitrate adaptation, licensing, monetization)
Output: 6 designs where you think about business + technical depth.
Week 7–9: Senior Lens on ML/Data/Infra
Choose your strongest domain OR the one you want to own at senior level:
If Backend/Data:
- Design: Distributed transaction system (ACID guarantees at scale)
- Design: Data warehouse (query optimization, cost, performance)
- Read: ML system design templates (even if not ML-track; understand ML infrastructure thinking)
- Deep dive: Consistency models (strong, eventual, causal)
- Mock: 3 backend-centric designs
If ML/Data Science:
- Design: Recommendation ranking at scale (10B queries/day)
- Design: LLM inference + serving (batching, caching, cost optimization)
- Read: ML testing + MLOps
- Deep dive: Feature store architecture; online/offline serving gaps
- Mock: 3 ML-centric designs
If Infra/SRE/Platform:
- Design: Observability system at scale (Prometheus + tracing + logs)
- Design: Canary deployment + incident detection system
- Read: incident response, observability
- Deep dive: Distributed tracing; cost of observability
- Mock: 3 infra-centric designs
Output: Expertise in your domain; ability to talk to cross-functional leads.
Week 10–11: Leadership + Strategic Thinking
This is what separates L5 from L6.
| Activity | Time | Focus |
|---|---|---|
| Mon: Write 10 leadership stories (vs. mid's 15 generic ones) | 2h | Emphasize: decisions, outcomes, influence |
| Tue: Record yourself; focus on impact metrics | 1h | "We improved X by Y%; it saved Z" |
| Wed: Mock behavioral (90 min; hard questions: "Tell me about a time you disagreed with your manager") | 1.5h | Leadership signal |
| Thu: Debrief behavioral; identify weak stories; replace them | 1h | Iterate |
| Fri: Full loop mock: Coding (60 min) + Design (90 min) + Behavioral (60 min) | 3.5h | Full pressure test |
| Sat: Debrief full loop; score on rubric | 1h | Calibrate |
| Sun: Rest | Rest | Rest |
Interview readiness check: Are you scoring 4.5+ across all dimensions? If not, identify weak area and focus Week 12 on that.
Output: Polished leadership narrative; full loop comfort.
PHASE 3: APPLICATION & LOOP (Weeks 12–16)
Mindset: You're selective. Target 2–3 companies. Go deep.
Time commitment: 10–12 hours/week (mostly interviews; less prep)
Week 12: Targeting + Deep Dive
| Day | Activity | Output |
|---|---|---|
| Mon | Identify 2–3 target companies (don't spray resume) | Final list + research |
| Tue | Research each company's engineering culture, scale, challenges | Deep notes |
| Wed | Tailor resume/cover for each company; emphasize relevant scale | Custom materials |
| Thu | Reach out to network at each company (LinkedIn, prior colleagues) | Referrals |
| Fri | Apply officially; include referral or custom cover letter | Applications sent |
| Sat–Sun | Maintain coding (2 problems/week; easy/medium to stay warm) | Light prep |
Expected: 1–2 recruiter calls Week 13.
Week 13–14: Phone Screens
Assume 1–2 phone screens per company.
| Weekly Schedule | Activity | Time |
|---|---|---|
| 3x per week | Coding reps (1 per day; medium hard; 45 min) | 2.5h/week |
| 1x per week | System design deep dive (new problem; untimed; 90 min) | 1.5h/week |
| As scheduled | Phone screen (with company) | 1–2h |
Debrief after each screen: What went well? What surprised you?
Apply to parallel backup companies: If 1 company slow, have 2–3 more in pipeline.
Expected outcome: 1–2 advances to onsite by Week 14.
Week 15: Onsite Preparation
Assume 1–2 onsites scheduled for Week 15–16.
| Daily Routine | Time |
|---|---|
| Morning: Coding warm-up (2 problems; easy/medium; 45 min) | 45 min |
| Mid-day: Deep system design (new problem; 2 hours; focus on reasoning not speed) | 2h |
| Evening: Behavioral prep (record 2 stories; iterate; 45 min) | 45 min |
| Onsite day: Interview + debrief (3.5–4.5 hours) | 4h |
Before onsite: Review company-specific hiring archetype; know what they care about.
Week 16: Decision + Negotiation
| Activity | Timeline | Expected |
|---|---|---|
| Offers received | Week 15–16 | 1–2 offers |
| Debrief feedback | Week 16 | Understand your strongest loop |
| Negotiate | Week 16 | Use playbook; emphasize your senior impact |
| Decide | Week 16 | Accept offer |
Senior negotiation tip: Emphasize scope not just salary. What will you own? What's the bar for promotion to principal?
Success Metrics
By Week 3
- ✅ Senior bar understood
- ✅ DSA speed maintained (< 20 min for hard problems)
- ✅ 1 mock coding scored 4.5+
By Week 11
- ✅ 9+ systems designed at principal level
- ✅ Domain expertise clear
- ✅ 10 leadership stories; 3+ with strategic decisions
- ✅ Full loop mock scored 4.5+ across all dimensions
By Week 16
- ✅ 2+ onsites completed
- ✅ 1+ principal/senior offer
- ✅ Negotiation complete; offer accepted
Daily Routine (Senior)
Time budget: 12 hours/week = ~1.5–2 hours/day average
- Quick: 2 coding problems (45 min total; warm-up + explain)
- Deep: 1 system design OR leadership prep (90 min)
- Optional: Read (30 min; blogs, papers, architecture docs)
Reality: Some days you'll do 4 hours (interview day); others just 30 min (maintenance).
Interview Strategy
Coding Round
- Approach: Solve correctly first; then optimize.
- Communication: Explain your thinking out loud; don't hide.
- Red flag: If you get stuck, ask clarifying questions; don't sit silent.
System Design Round
- Approach: Take 5 min to clarify requirements; then design slowly.
- Communication: Discuss tradeoffs explicitly. "Option A is faster but costs more. Option B is cheaper but has latency. Here's why I'd choose A..."
- Senior-level thinking: Ask about business requirements first; don't assume technical specs.
- Red flag: If you're moving too fast, slow down. This is about judgment, not speed.
Behavioral Round
- Approach: Tell stories that show decisions you made, not just actions you took.
- Communication: Include metrics. "We improved latency from 200ms to 50ms, which increased conversion by 3%, worth $2M ARR."
- Senior-level thinking: Discuss tradeoffs in your decisions. "We could have done X, but chose Y because of Z..."
- Red flag: If your stories don't include business impact, rewrite them.
Red Flags (Adjust Plan if You See These)
- ⚠️ Week 4: Can't design a system that feels "principal-grade" → Read more theory; study existing senior designs; slow down
- ⚠️ Week 8: Your domain expertise isn't landing → Shift focus; pick a different specialization
- ⚠️ Week 12: No recruiter calls after referrals → Reach out more aggressively; consider lateral roles (not just staff track)
- ⚠️ Week 14: Phone screen feedback is "too confident" or "too detailed" → Calibrate your style; ask interviewer what they're looking for
Resources
- System design: Palantir interviews, Jane Street blogs, Stripe Press
- Coding: LeetCode Hard, but focus on communication (screenshare with peer)
- Behavioral: Leadership principles for your target companies
- Negotiation: Salary guide + talk to current senior engineers at target companies
You've prepared well. 16 weeks to a senior/principal offer. 🚀