Concept && Coding

Learn system design with Concept && Coding, step by step

80 videos in 5 steps, about 33 h 52 min of watching. Start at step 1 and move down.

1. 1Start here: the basicsNo background needed. What the main ideas are and why they exist.6 videos · 1 h 9 min0/6

   • 1.1 Network FundamentalsBeginner · 2 min · 5.9K views · 2026How data moves reliably (or quickly) across a network.
   • 1.2 2. CAP Theorem (Hindi) | High Level Design for Beginners | CAP Partition Tolerance explainedBeginner · 19 min · 142.4K views · 2022Designing for Beginners: what it must do, the main parts, and the trade-offs.
   • 1.3 Event Driven Architecture (EDA) IntroductionBeginner · 30 min · 110.5K views · 2026Passing work and events between services without waiting for each other.
   • 1.4 Introduction of EDA(Event Driven Architecture) #softwareengineerBeginner · 2 min · 12.3K views · 2026Passing work and events between services without waiting for each other.
   • 1.5 What is Kafka? #softwareengineerBeginner · 2 min · 10.1K views · 2025Passing work and events between services without waiting for each other.
   • 1.6 Kafka Streams Introduction: Problems It Solves in Real SystemsBeginner · 15 min · 4.4K views · 2026Passing work and events between services without waiting for each other.
2. 2The building blocksCaches, queues, databases, load balancers: the parts every design is made of.22 videos · 7 h 11 min0/22

   • 2.1 Git Remote Repository (Part 1) | Connect Existing Local Project to GitHub (HTTPS & SSH) | Git PushIntermediate · 44 min · 2.1K views · 2026How web requests and responses travel between a browser and a server.
   • 2.2 AWS Auto Scaling Group (ASG) Explained | Automatically Scale EC2 InstancesIntermediate · 28 min · 3.6K views · 2026How a system grows from one server to many without falling over.
   • 2.3 AWS Application Load Balancer (ALB) Explained & Complete Hands-On Setup | EC2 + ASGIntermediate · 49 min · 10.6K views · 2026How traffic is spread across servers so no single one is overloaded.
   • 2.4 AWS Load Balancer #softwareengineerIntermediate · 2 min · 3.7K views · 2026How traffic is spread across servers so no single one is overloaded.
   • 2.5 Spring boot @Transactional Annotation - Part1Intermediate · 25 min · 90.8K views · 2024How databases store and find data, and what guarantees they give.
   • 2.6 Database Indexing and B+ Tree #softwareengineerIntermediate · 2 min · 7.2K views · 2025How databases store and find data, and what guarantees they give.
   • 2.7 Design High Availability SystemIntermediate · 2 min · 8.5K views · 2026What you give up to stay available or correct when machines fail.
   • 2.8 Kafka Schema Registry #softwareengineerIntermediate · 3 min · 27.8K views · 2026Passing work and events between services without waiting for each other.
   • 2.9 Why is Kafka so fast? #softwareengineerIntermediate · 2 min · 12.9K views · 2026Passing work and events between services without waiting for each other.
   • 2.10 Kafka TransactionIntermediate · 2 min · 10.9K views · 2026Passing work and events between services without waiting for each other.

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3. 3Design whole systems (HLD)Put the blocks together for a real product, step by step.19 videos · 7 h 15 min0/19

   • 3.1 API GATEWAY and Microservices Architecture | How API Gateway act as a Single Entry Point?Intermediate · 23 min · 235.7K views · 2024How services expose and call each other's features.
   • 3.2 1. Network Protocols (Hindi), High Level Design | Client Server vs P2P Model | webSocket vs WebRTCIntermediate · 14 min · 224.2K views · 2022Pushing updates to users instantly instead of making them ask.
   • 3.3 16. System Design - Distributed Messaging Queue | Design Messaging Queue like Kafka, RabbitMQIntermediate · 45 min · 168.7K views · 2023Designing Messaging Queue like Kafka: what it must do, the main parts, and the trade-offs.
   • 3.4 5. Scale from ZERO to MILLION Users (Hindi) | System design interview: Scale to 1million usersIntermediate · 35 min · 152.9K views · 2022Designing interview: what it must do, the main parts, and the trade-offs.
   • 3.5 Mock Low Level System Design Interview with Qualcomm Sr. Engineer - Design Meeting SchedulerIntermediate · 37 min · 132.6K views · 2022Designing Meeting Scheduler: what it must do, the main parts, and the trade-offs.
   • 3.6 6. Consistent Hashing in Hindi with Example | System Design - Consistent Hashing | High Level designIntermediate · 32 min · 117.4K views · 2022Clever data structures that make big lookups cheap.
   • 3.7 Kafka Architecture - Part1 | Event Driven ArchitectureIntermediate · 32 min · 58.6K views · 2026Passing work and events between services without waiting for each other.
   • 3.8 Spring boot: Security (Part-1) | Architecture and SetUpIntermediate · 18 min · 50.5K views · 2025A walk through how a real product is put together: what it must do, the parts, and the trade-offs.
   • 3.9 23. Two Phase Locking (2PL) | System DesignIntermediate · 41 min · 40.5K views · 2023A walk through how a real product is put together: what it must do, the parts, and the trade-offs.
   • 3.10 28. BUG in Double-Checked Locking of Singleton Pattern & its Fix | Low Level System Design QuestionIntermediate · 20 min · 27.3K views · 2023Designing Question: what it must do, the main parts, and the trade-offs.

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4. 4Low-level design (LLD)Classes, patterns and clean code inside one service.25 videos · 11 h 3 min0/25

   • 4.1 Ultimate LLD and HLD Roadmap | System Design RoadMap | LLD & HLD Topics to be covered for InterviewBeginner · 11 min · 1.5M views · 2022Designing the classes and patterns inside one service, so the code stays easy to change.
   • 4.2 2. Strategy Design Pattern explanation (Hindi) | LLD System Design | Design pattern in JavaIntermediate · 17 min · 330.2K views · 2022Designing the classes and patterns inside one service, so the code stays easy to change.
   • 4.3 1. OOPs Concept in Java with Examples | 4 Pillars of Object Oriented Programming (OOPs)Advanced · 1 h 37 min · 246.4K views · 2023Designing the classes and patterns inside one service, so the code stays easy to change.
   • 4.4 27. All Creational Design Patterns | Prototype, Singleton, Factory, AbstractFactory, Builder PatternIntermediate · 29 min · 216.4K views · 2023Designing the classes and patterns inside one service, so the code stays easy to change.
   • 4.5 4. Decorator Design Pattern Explanation with Java Coding (Hindi) | LLD System DesignIntermediate · 23 min · 190.4K views · 2022Designing the classes and patterns inside one service, so the code stays easy to change.
   • 4.6 4. SAGA Pattern | Strangler Pattern | CQRS | Microservices Design Patterns | System DesignIntermediate · 31 min · 189.4K views · 2022Designing the classes and patterns inside one service, so the code stays easy to change.
   • 4.7 3. Microservices Design Patterns | Part1: Introduction and Decomposition Pattern | HLDBeginner · 29 min · 170.3K views · 2022Designing the classes and patterns inside one service, so the code stays easy to change.
   • 4.8 10. Design Logging System (Hindi) | Chain of Responsibility Design Pattern | System Design interviewIntermediate · 15 min · 132.5K views · 2022Designing the classes and patterns inside one service, so the code stays easy to change.
   • 4.9 32. All Structural Design Patterns | Decorator, Proxy, Composite, Adapter, Bridge, Facade, FlyWeightAdvanced · 51 min · 99.3K views · 2023Designing the classes and patterns inside one service, so the code stays easy to change.
   • 4.10 What is LLD (Low Level Design)Beginner · 17 min · 78.8K views · 2025Designing the classes and patterns inside one service, so the code stays easy to change.

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5. 5Go deeperInternals, trade-offs and how large systems really behave.8 videos · 7 h 15 min0/8

   • 5.1 21. Database Indexing: How DBMS Indexing done to improve search query performance? ExplainedAdvanced · 1 h 24 min · 183.9K views · 2023How databases store and find data, and what guarantees they give.
   • 5.2 Kafka Consumer Advanced Configurations and Properties (Edge Cases) | Part-3Advanced · 36 min · 5.7K views · 2026Passing work and events between services without waiting for each other.
   • 5.3 Kafka Streams Windowing Explained (Tumbling, Hopping & Session Windows)Advanced · 53 min · 3K views · 2026Passing work and events between services without waiting for each other.
   • 5.4 Spring Boot Roadmap 2024 | Spring Boot with Microservices from Basics to AdvancedAdvanced · 11 min · 507.9K views · 2024When to split an application into services, and what it costs.
   • 5.5 AWS S3 Part3: Upload, MultiPartUpload, Download APIsAdvanced · 57 min · 7K views · 2026How services expose and call each other's features.
   • 5.6 Distributed Tracing in-depth | Micrometer and Open TelemetryAdvanced · 1 h 11 min · 25.1K views · 2025How many machines agree on one answer, even when some fail.
   • 5.7 Distributed Scheduler (Part 1) – Internal working of Scheduler : Leader-Follower PatternAdvanced · 59 min · 7.6K views · 2026How many machines agree on one answer, even when some fail.
   • 5.8 System Design: Concurrency Control in Distributed System | Optimistic & Pessimistic Concurrency LockAdvanced · 1 h 5 min · 234.4K views · 2023Doing many things at once without breaking shared data.

Order and levels are picked by us from titles and lengths. The one-line notes are ours. Every video plays from YouTube and belongs to Concept && Coding.

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