Build with AI tools and verify normal, boundary, and failure cases. Choose practice or a timed exam.
Level 1
Foundations · Data and input
Build with AI and verify your work. Practice real-world, algorithm and AI systems problems, then take a timed challenge.
AI Native record
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10 problems
- Practice
Project search
Search names and tags without changing the input.
Data processingLevel 160 min - Practice
Normalize profile inputs
Clean up strings and report invalid fields.
Data processingLevel 145 min - Practice
Deduplicate events
Keep the latest event per ID in a stable order.
Data processingLevel 145 min - Practice
Paginate search results
Build pagination that handles boundary values.
BackendLevel 130 min - Practice
Repair search filters
Fix whitespace, duplicate tags, defaults, and input mutation in existing code.
Bug repairLevel 145 min - Practice
Create shareable slugs
Normalize Unicode labels into stable URL slugs.
Data processingLevel 130 min - Practice
Redact nested secrets
Mask sensitive fields in nested JSON logs.
Security & accessLevel 145 min - Practice
Sort release versions
Compare numeric version segments with stable ties.
AlgorithmsLevel 145 min - Practice
Plan API retries
Apply capped exponential backoff and stop conditions.
ReliabilityLevel 130 min - Practice
Repair cursor pagination
Repair mutation and off-by-one cursor behavior.
Bug repairLevel 145 min