Category / Field notes+

Engineering

Web fundamentals, system design, and practical notes on how the stack works under the hood

10 articles

§ 01 — Category index+

All notes in Engineering

OAuth 2.0 and OpenID Connect in Depth: Authorization Flows and Social Login in Practice

A practical guide to OAuth 2.0 and OpenID Connect covering authorization code flow, PKCE, ID tokens, scopes, social login, redirect URI security, and production mistakes.

Engineering — Aug 15, 2026 — Production Backend Systems#oauth #oidc #openid-connect

Sessions vs JWTs: Where Tokens Live, How They Expire, and Why It Matters

A practical comparison of server-side sessions and JWT authentication, covering storage, cookies, expiry, revocation, refresh-token rotation, browser security, and production tradeoffs.

Engineering — Aug 3, 2026 — Production Backend Systems#authentication #sessions #jwt

Authentication vs Authorization in Depth: Sessions, JWTs, RBAC, ABAC, and Access Control

A practical guide to authentication and authorization covering sessions, JWTs, access tokens, refresh tokens, RBAC, ABAC, tenant boundaries, and production access-control mistakes.

Engineering — Jul 19, 2026 — Production Backend Systems#authentication #authorization #jwt

Production Debugging: A Practical Framework for Web Request Issues

A practical, layer-by-layer framework for debugging production web issues: slow pages, failed requests, redirect loops, DNS problems, TLS errors, CORS failures, and hydration mismatches.

Engineering — Jul 17, 2026 — How the Web Works#debugging #devtools #observability

Browser Rendering in Depth: DOM, CSSOM, Layout, Paint, Compositing, and Hydration

A practical guide to how browsers turn HTML, CSS, and JavaScript into pixels, covering the DOM, CSSOM, render tree, layout, paint, compositing, hydration, and Core Web Vitals.

Engineering — Jul 15, 2026 — How the Web Works#browser-rendering #dom #cssom

Server-Side Request Flow in Depth: Proxies, Middleware, Auth, Rate Limiting, and Observability

A practical guide to what happens inside a server once a request arrives, covering reverse proxies, load balancers, middleware, routing, auth, rate limiting, database access, and observability.

Engineering — Jul 13, 2026 — How the Web Works#backend #middleware #reverse-proxy

TLS and HTTPS in Depth: Handshakes, Certificates, SNI, ALPN, HSTS, and OCSP

A practical guide to TLS and HTTPS, covering the TLS 1.3 handshake, certificate chains, SNI, ALPN, cipher suites, forward secrecy, HSTS, OCSP, and how to debug common SSL failures.

Engineering — Jul 11, 2026 — How the Web Works#tls #https #ssl

DNS in Depth: Resolvers, Records, TTL, and Production Debugging

A deep, practical guide to DNS covering the resolution path, record types, TTL and propagation, DNSSEC, split-horizon DNS, and how to debug DNS issues in production.

Engineering — Jul 9, 2026 — How the Web Works#dns #dnssec #networking

HTTP in Depth: Methods, Status Codes, Headers, Caching, Cookies, and CORS

A deep, practical guide to HTTP covering methods, status codes, headers, caching strategy, cookies, CORS, and content negotiation, from fundamentals to production debugging.

Engineering — Jul 7, 2026 — How the Web Works#http #http2 #http3

What Happens When You Press Enter in a Browser?

A practical map of what happens after you press Enter, from URL parsing and DNS to HTTP, server processing, browser rendering, hydration, and debugging.

Engineering — Jul 5, 2026 — How the Web Works#browser #dns #tcp