A strong first developer interview prep plan covers four buckets in 14 days. Coding fundamentals and debugging take days 1-4. Portfolio deep-dives take days 5-7, API and system design basics days 8-10, and behavioral stories plus mock interviews days 11-14.
Interviewers look for clear thinking and coachability more than perfect answers. This pack gives you the daily structure, based on what Staff Engineers and hiring managers evaluate in junior candidates.
Table of Contents
- What you can show interviewers after 14 days
- The four buckets the plan covers
- How to prepare day by day
- What to check on interview day
- FAQ
- Reliable resources
- Related guides in this series
What you can show interviewers after 14 days
The plan aims at what a Staff Engineer looks for. Strong junior candidates demonstrate:
- structured problem-solving under uncertainty
- clean communication of assumptions and trade-offs
- ownership mindset with willingness to ask clarifying questions
- quality awareness (tests, failure handling, observability basics)
None of these require perfect answers. They require clear thinking and coachability.
The four buckets the plan covers
- Coding fundamentals
- Project storytelling
- API/system design basics
- Behavioral communication
Each bucket gets its own block of days, in this order.
How to prepare day by day
Days 1-4: core coding and debugging
- Solve 2-3 medium-level problems daily
- Practice talking through thought process
- Review mistakes and rewrite one clean solution
Days 5-7: portfolio and project deep-dives
- Prepare 2 project walk-throughs
- Explain trade-offs and architecture choices
- Practice answering “what would you improve next?”
Days 8-10: API and system basics
- Design one small REST API per day
- Discuss data model, validation, auth, and monitoring
- Explain failure modes and retry strategy
Add one short reliability question in your prep each day:
- What fails first?
- How will I detect it?
- How will I recover safely?
Days 11-14: behavioral stories and mock interviews
- Prepare 6-8 STAR stories
- Run at least 2 mock interviews
- Refine concise and structured answers
What to check on interview day
- Confirm role + interview format
- Review your resume and projects
- Prepare 3 thoughtful questions for interviewer
- Bring one notebook with key examples
Use these high-signal questions:
- “What does success look like for a junior engineer in the first 90 days here?”
- “How does your team review architecture and technical trade-offs?”
- “What quality standards are most important in this codebase?”
FAQ
How much system design should a junior candidate know?
You only need fundamentals: API boundaries, data modeling basics, error handling, and trade-off reasoning.
Is behavioral prep as important as coding prep?
Yes. Many candidates are technically capable. Communication quality often determines final decisions.
How long should junior developer interview prep take?
This plan takes 14 days. It covers coding and debugging, project deep-dives, API and system basics, then behavioral stories and mock interviews.
Reliable resources
For the other end of the ladder, Staff Engineer interview: the four rounds shows how the questions change when scope, not speed, is being scored.