# Beyond LeetCode: From Interview Prep to Real Engineering

## You Passed the Interview. Now What?

You spent months grinding LeetCode. You mastered:
- Binary search variations
- Dynamic programming patterns
- Graph traversal algorithms
- Two-pointer techniques

You got the offer. Congratulations!

**Day 1 on the job**: "Here's the codebase. We need you to add a feature that requires database migrations, API changes, and Docker updates."

None of your LeetCode practice prepared you for this.

## The LeetCode Gap

LeetCode is excellent for what it does: **prepare you for coding interviews**.

But it doesn't teach:
- Building complete systems
- Designing APIs
- Managing databases
- Evolving existing code
- Working with Docker
- Making architecture decisions

These are **day-to-day backend engineering tasks**.

## What Real Backend Work Looks Like

### Task: "Add user roles feature"

**What LeetCode taught you**: Implement a role-checking algorithm

**What the job requires**:
1. Design the database schema changes
2. Write migrations to preserve existing data
3. Update the API endpoints
4. Maintain backward compatibility
5. Add proper error handling
6. Write integration tests
7. Update Docker configs
8. Deploy without downtime

LeetCode prepared you for step 1's algorithm. The other 7 steps? You're on your own.

## From Algorithms to Systems

### LeetCode Mindset
- Isolated problem
- Pure function
- Optimal Big-O complexity
- Single correct answer
- No state, no side effects

### Production Mindset
- System integration
- Multiple services coordinating
- Good enough performance (with room to scale)
- Many valid approaches
- Persistent state, side effects everywhere

Both mindsets are valuable. But only one helps you on day 1 of the job.

## The Skills Gap

### What LeetCode Teaches Well
✅ Algorithm design
✅ Data structure usage
✅ Optimization techniques
✅ Problem-solving patterns
✅ Coding interview performance

### What LeetCode Doesn't Cover
❌ System architecture
❌ Database design
❌ API design
❌ Docker deployment
❌ Schema migrations
❌ Service orchestration
❌ Production workflows

## Filling the Gap

You could:

**Read books** - Get theory without practice

**Watch videos** - See others do it, but never do it yourself

**Build side projects** - But how do you know you're doing it right?

**Get a job** - And struggle for months to catch up

**Or use YoloCorp** - Structured practice of real engineering

## YoloCorp: The Next Step After LeetCode

### Real Systems, Not Toy Apps

Build production-like backends:
- Design APIs from scratch
- Choose and configure databases
- Write Docker configurations
- Handle evolving requirements
- Manage persistent data

### Progressive Complexity

**Episode 1**: Basic CRUD (achievable for LeetCode grinders)
**Episode 5**: Complex business logic
**Episode 10**: Real architectural challenges

Learn incrementally, like onboarding at a real job.

### Decision Making Practice

LeetCode problems have expected solutions. Backend engineering requires decisions:

**Database Choice**: SQL or NoSQL? Postgres or MySQL?
**API Design**: REST, GraphQL, or RPC?
**Architecture**: Monolith or microservices?
**Storage**: Where does this data live?

Make these decisions in a safe environment.

### Evolving Requirements

LeetCode problems never change. Production requirements always change.

YoloCorp simulates this:
- Episode 5 adds feature that challenges your episode 1 decisions
- Must migrate data and refactor code
- Learn to design for change
- Experience real engineering constraints

## Complementary Skills

**LeetCode → Job Interview**
- Whiteboard coding
- Algorithm optimization
- Interview performance

**YoloCorp → Job Performance**
- System design
- Production engineering
- Day-to-day tasks

Use both to succeed in your career.

## From Interview Success to Job Success

### Week 1 at Work
**LeetCode helped**: Reading and understanding algorithms in the codebase
**YoloCorp helps**: Understanding the architecture, Docker setup, database schema

### Week 4 at Work
**LeetCode helped**: Implementing efficient data processing
**YoloCorp helps**: Adding the feature to the existing system, writing migrations, updating APIs

### Month 3 at Work
**LeetCode helped**: Code review comments about algorithmic efficiency
**YoloCorp helps**: Designing new features, making architecture decisions, handling production constraints

## Real Engineering Skills

After completing YoloCorp projects, you can:

**Talk Architecture**
> "I designed a REST API for this domain. Here's why I chose these endpoints and this data structure."

**Handle Complexity**
> "When requirements changed, I had to migrate the schema and refactor three services while maintaining backward compatibility."

**Deploy Systems**
> "I orchestrated multiple services with Docker Compose, configured health checks, and managed persistent volumes."

**Evolve Code**
> "I refactored the authentication system across 5 episodes as new requirements emerged, learning to design for change."

These are conversations you have at work, not in interviews.

## Career Growth

### Junior → Mid-Level
LeetCode gets you the junior role.
YoloCorp helps you perform and grow into mid-level.

### Mid-Level → Senior
LeetCode keeps your interview skills sharp.
YoloCorp gives you the system design experience seniors need.

## The Complete Picture

**Use LeetCode to**:
- Master algorithms and data structures
- Prepare for coding interviews
- Stay sharp on fundamentals

**Use YoloCorp to**:
- Learn backend engineering
- Practice system design
- Prepare for the actual job
- Build portfolio projects

Neither replaces the other. Both are valuable.

## Start Building

You've conquered LeetCode. Ready for the next challenge?

[Download the CLI](/downloads) and start building production-like backend systems.

**Think of it this way**: LeetCode taught you to solve problems. YoloCorp teaches you to build systems. You need both to be a complete engineer.