0.7 The series: OS → networking → security → HTTPS

This guide is one of seven, designed to be read as one course in this order:

   1  OS & Linux  ──▶  2  Networking  ──▶  3  Security  ──▶  4  HTTPS walkthrough
                         2a OSI map          3a From Zero        (one request through
                         2b TCP/IP           3b In Depth          every guide, in Go)
   ════════════════════  Go, alongside every step  ════════════════════

Step	Guide	What it gives you	Hands-on
1	Operating Systems, Linux, and Containers	the machine every request starts and ends on: processes, memory, files, sockets, containers, Kubernetes	9 Go labs (Part 20)
2a	The OSI Model, One Click at a Time	one click followed through all seven layers; the map for everything after it	concept map, 1 hour
2b	Networking from Zero (TCP/IP)	how machines talk: addressing, routing, TCP, TLS, packet capture, network operations	23 Go labs (§0.8)
3a	Security from Zero	encoding vs hashing vs encryption, TLS, PKI, SSH, the OWASP Top 10, threat modelling	OpenSSL labs and a vulnerable app to break
3b	Security Engineering in Depth ← you are here	cloud and Kubernetes security, distributed authorization, advanced web attacks, data protection, detection	10 Go labs + a `govulncheck` exercise (§0.8)
4	The HTTPS Request Lifecycle	one request end to end, then the server side built in Go; Chapter 25 traces one request through every guide	13 Go labs (§0.6, Ch 25)
∥	Go — The Complete Field Guide	the language behind every lab, plus the 120-day plan's multi-week projects	120-day plan

Why this order. Every network connection is a file descriptor owned by a process, so the OS comes first. Networking comes next, because every attack and defence in the security guides assumes you can follow a packet. Security comes third, because it needs both. The HTTPS walkthrough comes last because a single HTTPS request uses all of it, and its final chapter runs one request through every guide in a Go program. Go runs alongside the whole way: each guide's "Build it in Go" labs turn its chapters into code you can run.

Reading paths by role:

Backend engineer: 1 (Phases 1–2, Part 20) → 2a → 2b (Parts 1–7) → 3a (Parts 1–6) → 4 (all, including Part 9) → 3b (Parts 5–6).
SRE / platform: 1 (all) → 2a → 2b (all) → 3b (Parts 2–4, 8) → 4 (Parts 8–10).
Security engineer: 1 (Phases 1, 3) → 2a → 2b (Parts 3–8) → 3a → 3b → 4 (Chapters 12, 19–22, 25).
Engineering manager: 2a → 1 (Chapters 1–3, 44, 66, 72) → 3b (Part 9) → 4 (Chapters 13, 18, 23, 25).

Chapters link to each other directly, with "Across the series" notes where another guide covers a topic in more depth.