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Knowledge Hub

Knowledge Hub

Understand how systems work underneath, why a solution is chosen and what it costs. Every article has interactive diagrams, real measured output and a pre-production checklist.
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articles
198
interactive diagrams
117
glossary terms
208
learning paths
7

Updated10/28/2026 · content checked against official documentation

5 knowledge areas

Section titled “5 knowledge areas”

Data foundations

41 articles

PostgreSQL from how a row is stored to transactions and locks; caching with Redis.

Messaging & distributed systems

29 articles

Kafka, RabbitMQ and what tends to break when services call each other over the network.

Architecture & code

66 articles

Module boundaries, patterns, and how NestJS and Node.js work underneath.

Operations & quality

21 articles

Deploy safely, stay observable, block common vulnerabilities and keep tests from flaking.

Reference

3 articles

Case studies that put the pieces together, and a glossary for quick lookups.

Learning paths

Section titled “Learning paths”

Not sure where to start? Pick the goal closest to what you are working on, then read in order.

PostgreSQL foundations

New to backend and want to really understand the database

  1. ACID
  2. MVCC
  3. Isolation levels
  4. B-tree index
  5. Reading EXPLAIN

Slow queries

A slow query needs investigating right now

  1. Reading EXPLAIN
  2. Why the index is not used
  3. Statistics
  4. Join algorithms

On-call

Deploying and running services on Kubernetes

  1. Health probes
  2. Graceful shutdown
  3. SLI, SLO, error budget
  4. Correlation ID

Reliable messaging

Building consumers that never lose or duplicate a message

  1. Distributed log
  2. Commit offset
  3. Idempotent consumer
  4. Transactional outbox

Node.js / NestJS backend

Writing NestJS services and want to know how they run

  1. Event loop
  2. Streams and backpressure
  3. Request lifecycle
  4. Provider scope

Secure APIs

Designing public or B2B APIs

  1. BOLA / IDOR
  2. CORS and CSRF
  3. Session or JWT
  4. Rate limiting

Code quality

Write, review and run code like a senior

  1. Naming
  2. Clean code
  3. Common coding mistakes
  4. Transactions in code
  5. Secure coding
  6. Code review
  7. Git

What every article includes

Section titled “What every article includes”

Step-by-step diagrams

Click through each step to see where a request, lock or message goes, instead of reading a long paragraph.

Real, measured output

Plans, logs and numbers come from real PostgreSQL, Redis or Node runs, never made up.

Trade-offs and checklists

When to use it, when not to, and what to check before it goes to production.

Checked against official sources

Defaults, versions and limits all link to the original docs at the end of each article.

Every article has a level:BasicIntermediateAdvanced· the Prerequisitessection at the top lists the background worth reading first.