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READING NOTE · 027

Good systems start
with good questions.

Availability, latency, scalability. Start with the constraints that shape the system.

Revisit: what changes when the first bottleneck moves?

Study checkpoint 18 / 25 minNotes

Ideas worth
coming back to

Read. Build. Connect.

SCALE REVIEW · DECISION 08

Find the first
modeled constraint

Start with the query, understand the tradeoff, then build the simplest useful thing.

OPENAI & machine learningStart learning →

Everything an Anthropic
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A LIBRARY FOR EVERY PART OF YOUR STACK

GoPythonJavaScriptDjangoGitC++PostgreSQLMongoDBSQLCSSVim
DDIASystem designData structuresLinuxMarkdownAlgorithmsAI researchMachine learningTerminal
ScalabilitySortingWeb developmentDatabasesArchitectureResearchNotebooksInterview prep

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Programming languages

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System design in depth

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18 NOTES · ALL FREE
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AI & machine learning

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  • Research, papers and practical tools
  • Explore the AI learning landscape
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Databases & SQL

  • SQL queries and data modeling
  • PostgreSQL and MongoDB
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Tools for building

  • Django and web development
  • Git workflows and version control
  • Markdown, Vim and useful tools
5 NOTES · ALL FREE
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Data structures & algorithms

  • Sorting and problem solving
  • Programming interview study plan
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Terminal & hardware

  • Commands worth keeping close
  • ThinkPad setup and experiments
  • A practical developer workspace
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Go study notes

  • Types, control flow, and functions
  • Memory, pointers, and testing
  • Short lessons with practice
5 MODULES · 119 LESSONS
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Designing Data-Intensive Applications

  • Storage, replication, and transactions
  • Distributed systems and streaming
  • A sequenced path through DDIA
15 MODULES · 202 LESSONS
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Python notebooks

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Handwritten notes

  • Computer science on paper
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9 HANDWRITTEN PDFS
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Interview preparation

  • Make a practical study plan
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OPEN STUDY PLAN
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Research & references

  • Follow the next useful idea
  • Keep a shelf of good references
  • Explore, read, and build
OPEN REFERENCE SHELF
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CLOUD & INFRASTRUCTURE

From code to cloud

Build at the edge. Understand the cloud. Run your own cluster.

Illustrated Cloudflare field notebook

Cloudflare at the edge

  • Workers and serverless foundations
  • DNS, caching and the global network
  • R2, D1 and stateful applications
4 TOPICS · PATH PREVIEW
Illustrated Azure field notebook

Build with Azure

  • Compute, storage and cloud foundations
  • Identity and virtual networking
  • Deploy and observe your applications
4 TOPICS · PATH PREVIEW
Illustrated Kubernetes field notebook

Kubernetes in practice

  • Pods, deployments and services
  • Networking, configuration and storage
  • Scale, roll out and troubleshoot
4 TOPICS · PATH PREVIEW
THREE PATHS. ONE CONNECTED STACK.Start with system design
EDGE & SERVERLESS / PATH PREVIEW

Cloudflare at the edge

Start with the network. Then bring your code, data, and applications closer to the people using them.

  1. Understand the edge

    Trace a request through DNS, the network, and the cache.

  2. Build with Workers

    Explore request handlers, bindings, and local development.

  3. Choose your storage

    Get oriented with R2 object storage, D1, and Durable Objects.

  4. Connect the pieces

    Follow an official tutorial from your first request to deployment.

A starting map for your learning. Continue with the official guides and tutorials.

Open Cloudflare guides
CLOUD FOUNDATIONS / PATH PREVIEW

Build with Azure

Build a mental model of the cloud, from your first resource group to the services that keep an application running.

  1. Learn the foundations

    Explore subscriptions, resource groups, regions, and cloud concepts.

  2. Run your application

    Compare virtual machines, App Service, and container hosting.

  3. Connect and protect

    Get familiar with virtual networks, Microsoft Entra ID, and access control.

  4. Operate with confidence

    Explore monitoring, deployment workflows, and cost management.

A starting map for your learning. Continue with the official guides and tutorials.

Open Azure guides
CONTAINERS & CLUSTERS / PATH PREVIEW

Kubernetes in practice

Go from a container to a running system. Understand the objects, the control loop, and what happens inside a cluster.

  1. Meet the cluster

    Understand nodes, the control plane, and the desired-state model.

  2. Deploy a workload

    Work through Pods, Deployments, labels, and configuration.

  3. Expose and connect

    Explore Services, service discovery, and persistent storage.

  4. Keep it running

    Follow the official basics: inspect, scale, and update an application.

A starting map for your learning. Continue with the official guides and tutorials.

Open Kubernetes guides

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GoNotex / field notes↗

Learn Go, chapter by chapter.

Work through composite types, control flow, functions, pointers, and testing. Short lessons, code examples, exercises, and practical reviews.

FROM THE OPEN LIBRARY

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Read the note →
DDIANotex / field notes↗

Understand the data system.

Architecture, replication, transactions, consensus, and streaming. Follow a structured path through storage, distributed systems, and data processing.

FROM THE OPEN LIBRARY

One place to collect what you learn, connect the ideas, and keep going.

Read the note →
System DesignNotex / field notes↗

Start with the questions.

Features, APIs, availability, latency, scalability, durability. A practical guide to thinking through the system before you start building.

FROM THE OPEN LIBRARY

One place to collect what you learn, connect the ideas, and keep going.

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PythonNotex / field notes↗

Make the fundamentals stick.

From operators and strings to classes, generators, and the Python data model. Keep the examples close and work through them one at a time.

FROM THE OPEN LIBRARY

One place to collect what you learn, connect the ideas, and keep going.

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GitNotex / field notes↗

Keep a useful command close.

A compact reference for version control. Revisit the commands, try a workflow, and get back to what you were building.

FROM THE OPEN LIBRARY

One place to collect what you learn, connect the ideas, and keep going.

Read the note →
DatabasesNotex / field notes↗

Ask a better query.

SQL examples, relational concepts, joins, and database operations. A reference to return to when the next data question comes up.

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One place to collect what you learn, connect the ideas, and keep going.

Read the note →
JavaScriptNotex / field notes↗

Understand the language.

Notes and examples across modern JavaScript: arrays, functions, objects, promises, and asynchronous code.

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Read the note →
AlgorithmsNotex / field notes↗

Trace it. Then implement it.

Walk through sorting and problem solving. Start with the steps, understand the tradeoff, and write your own implementation.

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Read the note →
Developer ToolsNotex / field notes↗

A small shelf of useful things.

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AI & MLNotex / field notes↗

Find the next useful branch.

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Notex brings your technical learning into one place.

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Enter from any level and move at your own pace. Read a note, try an example, and follow the next useful branch.

Explore learning pathsExplore the library
@ Notex Notes
01Notesannotated reading02Notebooksworking examples03Referencesthe technical shelf04Toolsdeveloper essentials05Study planconnect the foundations
CONTENTS
OF THE LEARNING BOX

BEYOND THE NOTES

Everything else on notex.

01PYTHON NOTEBOOKS

Labs

Run it. Understand it.

→
02THE NOTE LIBRARY

Notes

A concept at a time

→
03REFERENCE SHELF

Research

Follow the next idea

→
04SHARED KNOWLEDGE

Study with me

Learn in the open

→
05LEARNING PATHS

Study plan

Learn in order

→
06HANDWRITTEN NOTES

Papers

Start with the first

→
07DEVELOPER TOOLS

Tools

The technical shelf

→
08TERMINAL & HARDWARE

The garage

Keep experimenting

→

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GoNotex / field notes↗

Learn Go, chapter by chapter.

Work through composite types, control flow, functions, pointers, and testing. Short lessons, code examples, exercises, and practical reviews.

FROM THE OPEN LIBRARY

One place to collect what you learn, connect the ideas, and keep going.

Read the note →
DDIANotex / field notes↗

Understand the data system.

Architecture, replication, transactions, consensus, and streaming. Follow a structured path through storage, distributed systems, and data processing.

FROM THE OPEN LIBRARY

One place to collect what you learn, connect the ideas, and keep going.

Read the note →
System DesignNotex / field notes↗

Start with the questions.

Features, APIs, availability, latency, scalability, durability. A practical guide to thinking through the system before you start building.

FROM THE OPEN LIBRARY

One place to collect what you learn, connect the ideas, and keep going.

Read the note →
PythonNotex / field notes↗

Make the fundamentals stick.

From operators and strings to classes, generators, and the Python data model. Keep the examples close and work through them one at a time.

FROM THE OPEN LIBRARY

One place to collect what you learn, connect the ideas, and keep going.

Read the note →
GitNotex / field notes↗

Keep a useful command close.

A compact reference for version control. Revisit the commands, try a workflow, and get back to what you were building.

FROM THE OPEN LIBRARY

One place to collect what you learn, connect the ideas, and keep going.

Read the note →

Keep company with
people doing the work.

Read the notes, rebuild the foundations, and share what you learn as you go. A little practice, one useful idea at a time.

Enter the library →Contribute on GitHub ↗

FAQ

Questions people
ask before starting.

Where should I start?

Start free. If you want programming fundamentals, open Python. For architecture and tradeoffs, open System Design. To find a particular topic, search the library.

What is inside the library?

Programming notes, system design, database references, developer tools, algorithms, handwritten PDFs, and Python notebooks. Everything comes from the existing Notex collection.

Is this only for interview prep?

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Can I contribute a correction?

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Where do my saved notes go?

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PYTHON / A FIRST EXAMPLE
def learn(topic):
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learn("something new")
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