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donnemartin/system-design-primer

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TLDR

Study guide and reference for designing large-scale software systems and preparing for system design interviews at tech companies.

Mindmap

mindmap
  root((repo))
    Core Concepts
      Trade-offs
      CAP Theorem
      Consistency Patterns
    System Components
      Load Balancers
      Caching Strategies
      Databases
      Message Queues
    Learning Resources
      Flashcard Decks
      Design Exercises
      Interview Prep
    Use Cases
      Senior Engineer Interviews
      System Architecture
      Scalability Learning

Things people build with this

USE CASE 1

Prepare for system design interviews at major tech companies by studying trade-offs, CAP theorem, and architectural patterns.

USE CASE 2

Learn how to architect scalable systems by understanding load balancers, caching, databases, and asynchronous messaging.

USE CASE 3

Build a shared vocabulary for discussing large-system design with flashcard decks and design exercises.

USE CASE 4

Teach yourself distributed systems concepts like replication, failover, microservices, and content delivery networks.

Tech stack

Python
Community-maintained open resource; specific license terms not detailed in explanation, but offered freely with translations and contributions accepted.

In plain English

This repository, called The System Design Primer, is an organized study guide for learning how to design large-scale software systems and for preparing for the system design interview that many tech companies include as part of their hiring process. The README frames it as an "organized collection" of resources gathered from across the web, plus the author's own summaries, to give learners a single place to study a broad and otherwise scattered topic.

The way it works is that the README itself is a long index of system design topics. It walks the reader through fundamental trade-offs and concepts: performance versus scalability, latency versus throughput, availability versus consistency including the CAP theorem, consistency patterns, availability patterns like fail-over and replication, the domain name system, content delivery networks, load balancers, reverse proxies, microservices and service discovery, databases covering relational systems and NoSQL variants, caching strategies, and asynchronism with message and task queues. Each section gives summaries with pros and cons and links to deeper reading. The repo also bundles spaced-repetition flashcard decks for system design, system design exercises, and object-oriented design, plus pointers to a sister repo on coding interview challenges.

Someone would use this when preparing for a senior engineering interview, learning to architect scalable systems, or teaching themselves the vocabulary of large-system design. The repository is community-maintained, accepts contributions and translations, and is offered in many languages. The full README is longer than what was provided.

Copy-paste prompts

Prompt 1
I'm interviewing for a senior role and need to understand CAP theorem and consistency patterns. Walk me through the trade-offs using examples from the System Design Primer.
Prompt 2
Help me design a scalable system using load balancers, caching, and databases. What are the pros and cons of each component?
Prompt 3
Create a study plan for system design using the flashcard decks and exercises from the System Design Primer.
Prompt 4
Explain the difference between latency and throughput, and when each matters in system design.
Prompt 5
I need to understand microservices and service discovery. What are the key concepts and trade-offs?
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