Engineering Knowledge Base
A practical, production-grade engineering knowledge base and interactive practice platform β designed for accelerated learning, architectural decision-making, and high-impact interview preparation.
How to Navigate This Platform
- Interactive Practice: Access the π Daily Quizzes and 𧩠LeetCode Daily to build daily consistency with instant feedback and cloud progress syncing.
- Visual Learning: Explore 60+ interactive SVG diagrams and animated protocol visualizers embedded across topics.
- Structured Roadmaps: Follow sequential paths from Foundations to Domain Specialization using the sidebar navigation.
Interactive Features & Practice Hubs
| Feature | Description | Access |
|---|---|---|
| π Daily Concept Quizzes | Live interactive practice canvas synchronized with our central Google Sheets question bank (β Java [1,000 Qs], π Spring Boot [5,120 Qs], ποΈ System Design [5,120 Qs], π All [11,240 Qs]). Supports topic/difficulty filtering, instant solution rationales, and accuracy tracking. | β Open Daily Quizzes |
| 𧩠LeetCode Daily Challenge | Daily featured algorithmic problem, random global challenge picker, and topic explorer covering curated high-yield interview problems. | β Open LeetCode Daily |
| π 20-Week DSA Roadmap | Comprehensive 20-week pattern-based algorithmic training curriculum from Two Pointers to Dynamic Programming and Advanced Graphs. | β 20-Week DSA Guide |
| π’ LeetCode Company-Wise | Frequently asked interview questions tagged by top tech companies (Google, Meta, Amazon, Microsoft, Apple, Uber, etc.). | β Company-Wise Questions |
| π¨ Interactive Visualizers | 60+ custom React SVG diagrams for distributed consensus (Raft), TLS 1.3 handshakes, Kafka internal pipelines, Linux kernel subsystems, and ISO 20022 payment flows. | Embedded throughout docs |
| π€ Cloud Progress & Sync | Sign in with Google to sync your reading completion, quiz scores, accuracy metrics, and custom study plans in real time via Cloud Firestore. | β Account Login |
Learning Paths & Knowledge Domains
Knowledge Base Architecture & Learning TracksClick any domain node to explore
Interview Preparation
System Design & Core Java
Comprehensive senior engineering interview prep covering 4-step system design blueprints, JVM internals, concurrency primitives, and behavioral leadership principles.
Core Modules & Focus Areas
System Design FrameworkJava 21+ & JVM InternalsDistributed TransactionsBehavioral STAR Matrix
Target: Software Engineers targeting Senior, Staff, and Backend roles.
1. Interview Preparation Track
A structured path for software engineers targeting Senior Backend, Distributed Systems, and Java/Spring roles.
Phase 1 β Foundations & Core Engineering
| # | Topic | Key Concepts Covered | Direct Link |
|---|---|---|---|
| 1 | Java Fundamentals & 21+ | Virtual Threads (Loom), Sequenced Collections (JEP 431), Scoped Values, Pattern Matching, JMM | β Java Overview |
| 2 | OOP & SOLID Principles | Encapsulation, Covariant returns, Diamond problem resolution, Liskov Substitution Principle | β Java OOP |
| 3 | Collections & Data Structures | HashMap bitwise bucket hashing, ConcurrentHashMap CAS node locking, ArrayList resizing formula | β Collections |
| 4 | Multithreading & Concurrency | AbstractQueuedSynchronizer (AQS), ReentrantLock, StampedLock, False Sharing @Contended, Memory Barriers | β Concurrency |
| 5 | JVM Internals & GC | Generational ZGC colored pointers, G1 GC regions, Tiered Compilation (C1/C2 JIT), Metaspace | β JVM Internals |
| 6 | Design Patterns & Architecture | Creational, Structural (Decorator, Proxy), Behavioral (Saga, Strategy, Observer) patterns | β Design Patterns |
Phase 2 β System Design & Distributed Systems
| # | System Design Topic | Core Architectural Focus | Direct Link |
|---|---|---|---|
| 1 | Interview Framework | 4-step structured system design interview blueprint & trade-off scoring | β Framework |
| 2 | Distributed Transactions | Two-Phase Commit (2PC), Saga Pattern (Orchestration vs Choreography), Transactional Outbox + Debezium CDC | β Distributed Transactions |
| 3 | Distributed Consensus & Replication | Raft majority quorum calculations, Multi-Paxos, Google Spanner TrueTime API vs CockroachDB HLC | β Distributed Systems |
| 4 | Consistent Hashing & Partitioning | Hash ring topology, virtual nodes (vnodes), replication factors, data migration | β Consistent Hashing |
| 5 | Distributed Caching & Stampede Defense | Cache-Aside vs Write-Behind, Redis Cluster 16384 hash slots, XFetch probabilistic early expiration | β Caching Strategies |
| 6 | Message Queues & Streaming | Apache Kafka partition allocations, zero-copy sendfile, Idempotent Producer PID deduplication | β Message Queues |
| 7 | API Design & Rate Limiting | RESTful idempotency keys, Distributed Token Bucket with Redis Lua scripts, gRPC vs REST | β API Design |
| 8 | Database Scaling & Storage Engines | B-Trees vs Log-Structured Merge-Trees (LSM-Trees write amplification), Sharding, Read Replicas | β Database Scaling |
| 9 | Microservices Resilience | Resilience4j Circuit Breakers, Bulkheads, Rate Limiters, Service Mesh mTLS | β Microservices |
| 10 | Observability & Telemetry | Distributed Tracing (OpenTelemetry), Metrics (Prometheus), Log Aggregation, SLI/SLO/SLA | β Observability |
Phase 3 β Behavioral & Leadership Strategy
| Topic | Focus | Direct Link |
|---|---|---|
| Big 8 Behavioral Themes | Conflict resolution, leadership, failure recovery, ambiguity, customer obsession | β Behavioral Guide |
| STAR / STAR-L Framework | Animated 4-step STAR timing rubric, action verbs, and lessons learned structure | β STAR Method |
| Amazon 16 Leadership Principles | Comprehensive breakdown of all 16 Amazon LPs with story strategies and questions | β Amazon LP Guide |
| Questions to Ask Interviewers | Curated questions to evaluate engineering culture, architecture maturity, and growth | β Questions to Ask |
2. DSA Coding Training (20-Week Master Curriculum)
A structured 20-week curriculum designed for algorithmic pattern recognition and mastery:
| Week | Algorithmic Pattern | Key Problem Types | Guide Link |
|---|---|---|---|
| W1 | Arrays & Prefix Sums | Subarray sums, running totals, difference arrays | β Week 1 |
| W2 | Two Pointers & Sliding Window | Container with most water, longest substring without repeats | β Week 2 |
| W3 | Linked Lists & Pointers | Fast/slow pointers, cycle detection, reverse linked lists | β Week 3 |
| W4 | Hash Tables & Sets | Group anagrams, frequency counting, LRU cache foundations | β Week 4 |
| W5 | Monotonic Stacks & Queues | Next greater element, daily temperatures, sliding window maximum | β Week 5 |
| W6 | Binary Trees & BST | Lowest Common Ancestor, level-order BFS, tree serialization | β Week 6 |
| W7 | Graph Foundations | Connected components, flood fill, topological sort (Kahn's) | β Week 7 |
| W8 | Advanced Graph Algorithms | Dijkstra's shortest path, Bellman-Ford, cycle detection | β Week 8 |
| W9 | Binary Search Patterns | Search in rotated sorted array, search space reduction | β Week 9 |
| W10 | Recursion & Backtracking | Subsets, permutations, combination sum, N-Queens | β Week 10 |
| W11 | Intervals & Sweep Line | Merge intervals, meeting rooms, insert intervals | β Week 11 |
| W12 | Heaps & Greedy Algorithms | Top K frequent elements, task scheduler, merge K sorted lists | β Week 12 |
| W13 | Dynamic Programming (1D) | House robber, coin change, longest increasing subsequence | β Week 13 |
| W14 | Dynamic Programming (2D & Strings) | Unique paths, edit distance, longest common subsequence | β Week 14 |
| W15 | Advanced Sliding Window | Minimum window substring, sliding window with multi-constraints | β Week 15 |
| W16 | Tries & Prefix Trees | Prefix matching, autocomplete, word search II | β Week 16 |
| W17 | Shortest Paths & MST | Kruskal, Prim, minimum spanning trees | β Week 17 |
| W18 | Disjoint Set Union (DSU) | Union-Find with path compression & rank optimization | β Week 18 |
| W19 | Bit Manipulation & Math | Single number, bitwise arithmetic, power sets | β Week 19 |
| W20 | Comprehensive Review & Mocks | Complex multi-pattern problems & mock interview simulations | β Week 20 |
3. Banking & Financial Core Architecture
In-depth technical reference for fintech, payment hub, and banking system developers:
| Area | Core Topics Covered | Direct Link |
|---|---|---|
| Payment Fundamentals | 10-step payment lifecycle, On-Us vs Off-Us routing, settlement types | β Banking Guide |
| ISO 20022 Standards | XML schema definitions for pain.001, pacs.008, pacs.002, pacs.004, camt.054 | β ISO 20022 Specs |
| Global Payment Rails | NPP (New Payments Platform), SWIFT gpi / ISO MX, BECS Direct Debit, BPAY, RTGS | β Payment Rails |
| Core Banking Ledger (CBS) | Double-entry accounting invariants, Booked vs Available balance posting, End of Day (EOD) | β Core Banking |
| Clearing & Settlement | Deferred Net Settlement (DNS) vs Real-Time Gross Settlement (RTGS), Multilateral netting | β Settlement Engine |
| Sanctions & AML Compliance | Real-time fuzzy sanctions screening (Jaro-Winkler), AML/CTF transaction monitoring | β Compliance & Fraud |
| Open Banking & FAPI | Consumer Data Right (CDR), OAuth 2.0 PKCE, FAPI 1.0 Advanced Security Profiles | β Open Banking |
4. AI Agents & Vibe Coding
Modern paradigms for agentic software engineering and LLM application design:
| Module | Core Topics | Direct Link |
|---|---|---|
| AI Agents Architecture | ReAct loops, planning agents, tool calling protocols, execution traces | β Agent Overview |
| Custom Skill Systems | Sandboxed skill registries, CLI harnesses, YAML schemas, MCP configs | β Skill Systems |
| Evaluation & Testing Harness | E2E agent validation, prompt regression suites, simulation sandboxes | β Harness Testing |
| Vibe Coding Workflows | Natural language coding loops, dynamic context iteration, prompt orchestration | β Vibe Coding |
| Context Engineering | RAG architectures, sliding context window budgeting, instruction pruning | β Context Engineering |
5. DevOps, Cloud & Infrastructure
Production engineering practices for scalable, resilient deployments:
| Domain | Key Technologies & Concepts | Direct Link |
|---|---|---|
| Containerization | Docker Engine internals (dockerd, containerd, runc), Multi-stage OCI layer builds | β Docker Architecture |
| Kubernetes | Control Plane & Worker topologies, Workload controllers, Service routing, CSI storage | β Kubernetes Architecture |
| GitOps CI/CD | ArgoCD reconciliation loops, declarative Canary deployments, Custom Resource Definitions | β GitOps Pipelines |
| Infrastructure as Code (IaC) | Terraform State DAG execution engine, declarative vs procedural drift detection | β IaC & Observability |
| AWS DVA-C02 Certification | 17-module complete preparation path (Lambda, DynamoDB, SQS/SNS, IAM, CloudFormation) | β AWS Certification Guide |
6. Engineering Books Knowledge Repository
Condensed key takeaways, architectural principles, and mental models from cornerstone literature:
| Book | Author | Core Focus | Notes Link |
|---|---|---|---|
| Effective Java | Joshua Bloch | 90 best practices: Generics, Lambdas, Concurrency, Serialization, Records | β Effective Java Notes |
| Designing Data-Intensive Applications (DDIA) | Martin Kleppmann | Storage engines, Replication logs, Partitioning, Distributed Transactions, Consensus | β DDIA Notes |
| Clean Code | Robert C. Martin | Functions, naming conventions, error handling, clean unit testing | β Clean Code Notes |
| Clean Architecture | Robert C. Martin | Hexagonal architecture, dependency inversion rule, boundaries | β Clean Architecture Notes |
| Cracking the Coding Interview | Gayle Laakmann McDowell | Data structures, technical interview mental frameworks, complexity trade-offs | β CTCI Notes |
| System Design Interview (Vol. 1 & 2) | Alex Xu & Sahn Lam | Large-scale production architectures (URL Shortener, Distributed Message Queue, Payments) | β SDI Notes |
Ready to Start?
Jump straight into the π Daily Quizzes or pick a topic from the left sidebar navigation to begin learning!