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145 topics: mental models, patterns, Go, Java, Python, real-world, performance, lock-free, debugging
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Pattern Pick
Bit Manipulation Patterns
DSA TemplateIntermediate
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Low Level DesignIntermediate
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Design a Notification System
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QUIC Protocol
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AI/ML System Design Interview
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41End-to-end architecture problems
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90Design patterns & practical code
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35Production systems & operations
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51TCP, HTTP, TLS, DNS & more
Concurrency
145Threads, channels, async, locks in Java + Python + Go
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38Consensus, replication & more
Linux Internals
84Kernel, networking & system calls
Cheat Sheets
24Quick reference cards for interviews
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Discover Today
TimescaleDB
Full PostgreSQL with time series superpowers bolted in at the storage layer
Kubernetes Architecture
Container orchestration platform born from Google's Borg. Automates deployment, scaling, self-healing, and rollback for containerized workloads.
PBFT — Practical Byzantine Fault Tolerance
PBFT handles Byzantine faults: nodes that can lie, send conflicting messages, or behave arbitrarily. Raft and Paxos only handle crash faults where nodes either work correctly or stop completely. If you need consensus in an adversarial environment, you need something like PBFT