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Start with Python
The friendliest first language. From hello world to building real apps.
Open →Interview prep
Follow the SDE Roadmap
10 phases. Curated questions. Solutions in Python, Java, and C++.
Open →Level up at work
Master System Design
Design real systems: rate limiters, feeds, payments, search.
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Featured roadmap
From "Hello World" to FAANG-ready
10 phases. Curated questions from arrays to dynamic programming. Solutions in Python, Java, and C++. Built around the same patterns that show up in real interviews.
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For beginners
- Moving Average from Data Stream Using Queue
- DSA Interview Checklist: 75 Must-Know Problems
- Queues and Deques: FIFO, Double-Ended, and Circular
- Recursion to Iteration: Converting Recursive Code
- Data Engineering Interview Prep — What to Expect and How to Win
- Rust Lifetimes Explained Simply with Examples
For interviews
- LeetCode Interval Problems: Merge, Insert, and Schedule
- LeetCode Two Pointer Patterns: The Complete Guide
- Deque Design Patterns — Sliding Window, Palindrome, Work Stealing
- Priority Queue Patterns — Top-K, Merge K Lists, Median, Dijkstra
- BFS Pattern with Queues: Level-Order and Shortest Path
- Design Circular Deque — Array-Based Implementation (LeetCode 641)
For production
- Real-World Airflow Patterns for Production Pipelines
- Deploying Apache Airflow to Production
- Data Engineering Interview Prep — What to Expect and How to Win
- CI/CD for Data Pipelines — Ship Data with Confidence
- Kafka Real-World Use Cases: How Top Companies Use It
- DSA in Real Systems: From B-Trees to Bloom Filters
Latest tutorials
View all →- Airflow Dynamic DAGs in Airflow: Patterns and Best Practices Master dynamic DAG generation in Airflow using DAG factories, dynamic task mapping, YAML configs, expand/reduce, and avoid common pitfalls.
- Airflow Building Custom Operators in Apache Airflow Learn to build custom Airflow operators from scratch with BaseOperator, hooks, templated fields, testing strategies, and packaging for reuse.
- Data Engineering Data Orchestration with Dagster Learn Dagster's software-defined assets, ops, jobs, schedules, and sensors. Includes a practical comparison with Apache Airflow.
- Data Engineering Data Partitioning Strategies for Scale Master hash, range, and list partitioning strategies. Learn to choose partition keys, avoid hot partitions, and scale your data systems.
- Data Engineering Apache Iceberg: The Modern Table Format Understand Apache Iceberg's architecture, schema evolution, time travel, and hidden partitioning. Learn why table formats matter for data lakes.
- Data Engineering Real-Time Data Streaming: Architectures and Patterns Learn real-time streaming architectures like Lambda, Kappa, CDC, and event sourcing. Understand when to choose streaming over batch processing.
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