---
id: platform-overview
area: platform
level: 1
title: "Platform & Infrastructure"
claim: "Runs a multi-machine NixOS and Proxmox estate — fifty-plus containers · declarative configuration · encrypted backups with a written restore runbook · and public ingress — sized to the hardware rather than the budget."
confidence: running
period: "2020–"
tech: [NixOS, Proxmox, Docker, Caddy, Tailscale, Borg, Kopia, AWS S3]
metrics: [{label: "containers in the estate", value: 50}, {label: "hosts", value: 4}, {label: "backup tiers", value: "Borg · Kopia · AWS"}]
artefacts: [{type: doc, label: "Declarative multi-host configuration", url: "content/platform/l3/platform-nixos.md"}, {type: doc, label: "Backups and restore runbook", url: "content/platform/l3/platform-backups.md"}, {type: doc, label: "A hand-written Nix package with an exit plan", url: "content/platform/l3/platform-tuios-package.md"}]
public: true
last_verified: 2026-10-26
tags: [platform, devops, nixos, docker, backups]
---

# Platform & Infrastructure

**Claim.** Fifty or more containers on a four-host estate, configuration declared rather than hand-applied, encrypted backups on three machines with a restore runbook beside them, and one public listener at the edge.

**Status.** Running. Figures trace to the approved metric set and the infrastructure reference; verified 2026-10-26.

**The constraint that shaped it.** The runtime host is memory-bound rather than CPU-bound. Every service in this estate carries a memory cap and is bound to loopback, which is why the platform reads as engineering under constraint instead of hardware shopping.

**Start here.** [The capability page](platform-estate.md) covers what runs, where, and what was rejected.