Free lesson · JavaScript Basic to Advance
The 30-Day Interview Prep Plan
A Concrete Plan
Most interview prep advice is generic. "Practice problems." "Review your fundamentals." "Stay calm." None of it tells you what to do today, or tomorrow, or the day after.
This Topic is a 30-day plan with daily sessions. It assumes you've completed Modules 1-13 of this course. It assumes you have 1-2 hours per day to study (more is fine, less is risky). It assumes you have an interview scheduled in approximately a month.
The 30-day plan structure:
Days 1-7: Deep review — work through Modules 1-13 selectively <br/> Days 8-14: Question practice — Topic 14.2 map + LeetCode/etc. <br/> Days 15-21: Mock interviews — full simulated rounds with feedback <br/> Days 22-28: Targeted weakness work — what failed in mocks <br/> Days 29-30: Light review + rest — peak too early and you crash <br/>
Each day below has specific work. Follow it as written for best results.
If your interview is sooner than 30 days, compress proportionally. Each "week" of activity should still happen — just shorter. If you have more than 30 days, repeat weeks 3 and 4 (mocks and weakness work).
Week 1: Deep Review (Days 1-7)
The goal of week 1 is to refresh and consolidate the material. Not new learning. Working through the most-tested Topics with focus.
Day 1. Re-read Topic 9.11 (Interview Lens: Event Loop) twice. Trace through three output-prediction puzzles out loud. The event loop is the most-asked deep question. Get this solid before anything else.
Day 2. Re-read Topic 6.7 (Interview Lens: Closures). Implement the four closure patterns from memory: private state, memoization, currying, event handler factory. Don't look at the Topic until you're done.
Day 3. Re-read Topic 8.7 (Interview Lens: this, Classes, OO Patterns). Implement new from scratch and Object.create from scratch. Walk through the four this rules out loud with examples.
Day 4. Re-read Topic 9.12 (Interview Lens: Promise Patterns). Implement Promise.all, Promise.race, and a retry function from scratch. These are common implementation interview questions.
Day 5. Re-read Topic 7.8 (Interview Lens: Objects and Prototypes). Trace through a four-level prototype chain by hand. Predict what instanceof returns at each level.
Day 6. Re-read Topic 12.7 (Interview Lens: Browser and DOM). Implement event delegation for a dynamic list. Build the GitHub user lookup tool from Topic 12.5's exercise.
Day 7. Light day. Read Topic 14.2 (Interview Question Map) end to end. Mark questions you can't answer cleanly. Those are your weak spots for week 2.
End of week 1 check: you should be able to articulate the answer to any "30-second answer" in Topic 14.2 without hesitation. If you can't, week 2 fixes the gaps.
Week 2: Question Practice (Days 8-14)
The goal of week 2 is fluency. Producing answers fast, with composure.
Day 8. Spend the session on whichever cluster from Topic 14.2 you struggled with most. Re-read the source Topics. Practice the 30-second answers out loud, recorded if possible. Listen back.
Day 9. Solve 3 medium LeetCode problems on Arrays/Hashmaps. Time yourself. Goal: 25 minutes per problem with clean explanation. Use the Stuck Protocol when needed.
Day 10. Solve 3 medium LeetCode problems on Strings. Same protocol as Day 9. Explain your approach to an imaginary interviewer.
Day 11. Solve 3 medium LeetCode problems on Trees/Graphs. Recursion is a strong test of explanation skill — practice articulating base cases and recursive cases out loud.
Day 12. Solve 3 medium LeetCode problems involving async/Promises. Find problems that require Promise.all, retry logic, or event-loop reasoning. There aren't as many as for arrays — search for "promise interview questions" if needed.
Day 13. A "weakness day." Look at your performance over days 9-12. The category you found hardest gets another session — 3 more problems.
Day 14. Light day. Re-read Topic 14.3 (Stuck Protocol). Watch one mock interview video online (search "FAANG JavaScript mock interview"). Note what the candidate does well and where they could improve.
End of week 2 check: you should be able to solve a medium LeetCode-style problem in under 30 minutes with clean explanation. If not, you need more practice problems before moving to mocks.
Week 3: Mock Interviews (Days 15-21)
The goal of week 3 is interview simulation. The pressure of being watched is different from solo practice. You need exposure.
Day 15. Schedule your first mock interview. AlgoInsight's Discord has free mocks (running them is my work as Head of Community). Sites like Pramp and Interviewing.io also offer them. Aim for one with someone you don't know personally — strangers add the pressure.
Day 16. Do the mock. Take careful notes during and immediately after. What did you struggle with? Where did the Stuck Protocol help? Where did you panic? Where did the interviewer give hints?
Day 17. Recovery day. Re-read the Topics that map to the weakest area from the mock. If you fumbled an event loop question, back to Topic 9.11. If async, Topic 9.12. Don't move on without addressing the gap.
Day 18. Schedule mock #2. Different interviewer if possible. Different role focus if you can (frontend vs backend, or just different style).
Day 19. Do mock #2. Compare your performance with mock #1. The goal isn't perfection — it's improvement. You should be visibly more composed by the second mock.
Day 20. Schedule mock #3. By the third one, you should be able to handle the format itself without anxiety. The remaining anxiety is about the specific questions, which is normal.
Day 21. Do mock #3. Light reflection day. Identify one specific behavior to change for week 4.
End of week 3 check: you've done 3 mocks, taken notes from each, and identified weakness patterns. Your composure should be measurably better than at the start of the week.
Interactive animation: The honest loop: do a mock, list every wobble, repair it with targeted work, then mock again.
Week 4: Targeted Weakness Work (Days 22-28)
Week 4 is the most personalized week. Specifics depend on what your mocks revealed. Some common patterns I see in candidates I mock-interview:
If you struggle with explanation under pressure: spend 3 sessions solving problems while recording yourself explaining out loud. Watch the recordings. Notice where you go silent, where you hedge, where you stumble. Pick specific phrases to use ("Let me walk through this with an example," "I'm going to choose X over Y because...").
If you struggle with implementation speed: practice typing out the patterns. Implement the same problem 5 times. After the third, you stop having to think about the syntax and can focus on the algorithm. This is muscle memory work.
If you struggle with edge cases: before coding, spend 2 minutes listing edge cases out loud. Empty input. Single element. Maximum size. Duplicates. Negative numbers. Then code with all of them in mind.
If you struggle with the Stuck Protocol itself: practice deliberately getting stuck on problems you can't solve. Use the protocol. Make the steps automatic.
If you have time: solve 1-2 hard problems per session. Hard problems sharpen the easier ones. If you can solve a hard, the medium feels easier.
Days 22-28 should be 4-5 deep practice sessions and 2-3 mock interviews. By the end of week 4, the mock format should feel routine and your specific weaknesses should be addressable.
Days 29-30: Light Review and Rest
Don't make the mistake of cramming the last two days. Tired, stressed candidates perform worse than rested, calm ones.
Day 29. Light review only. Re-scan Topic 14.2. Read Topic 14.3 (Stuck Protocol) one more time. Don't try to learn anything new.
Day 30. Rest. Take a walk. Sleep eight hours. Eat regular meals. The night before, lay out everything you'll need for the interview. Don't study.
Interactive animation: The last two days, protected: light retrieval, logistics and sleep - and no new topics or late-night cramming.
Common Pitfalls
Warning: The prep-plan traps.
Skipping mocks because they're uncomfortable. They're the most valuable part of the plan. The discomfort is the point — interview pressure is uncomfortable, and you need exposure to it.
Doing too many practice problems and no mocks. LeetCode-only candidates often crash in real interviews because they've never practiced under observation.
Studying the day of the interview. It doesn't help. Anything you cram in the morning is unstable knowledge. Sleep matters more.
Comparing yourself to other candidates. Your prep depends on your gaps. Someone else's plan might be irrelevant to your weaknesses. Trust the mock feedback over generic advice.
Treating the plan as gospel. This is the plan that worked for me and many AlgoInsight Discord members. Adapt it. If you can't do a mock on day 16, do it on day 17. Consistency over weeks matters more than perfect daily adherence.
What If Your Interview Is Sooner Than 30 Days?
Common scenarios:
14 days out. Compress weeks 1 and 2 into week 1 (only re-read the most important Interview Lens Topics and solve 6-8 practice problems). Use weeks 2 and 3 for mocks and targeted work.
7 days out. Skip deep review. Do 2 mocks, work on the specific weaknesses, and rest the day before.
3 days out. Don't study new material. One mock if available. Re-read Topic 14.3 (Stuck Protocol) twice. Rest.
Tomorrow. Sleep. Eat well. Read Topic 14.3 once. Trust what you know.
Try It
Exercise: Print or screenshot this Topic. Cross off each day as you complete it. Track your performance in the mocks — what you struggled with, what you improved on, what felt good.
Don't skip days. Don't cram. The plan is designed to peak you at the right moment. Trust the structure.
If you fall off-track for a few days (life happens), don't give up. Just resume where you are, not where you'd planned to be. Half a plan executed is better than a perfect plan abandoned.