Insights/Article

Privacy by Design: Building a Local-First Smart Home

Cloud is useful—but should be optional. Here’s how we keep critical automations and data at the edge while still enjoying modern conveniences.

11 min readPrivacySecurity
Local-first home automation diagram
Local-first home automation diagram
Key takeaways
  • Strong DNS, DoT/DoH where appropriate
  • Turn off UPnP unless explicitly required
  • Auto-patch the edge hub on a maintenance window

Introduction

Local-first doesn’t mean anti-cloud; it means your home keeps working when the internet blinks. The trick is to keep safety and daily comfort on hardware you control, and use cloud where it truly helps.

These are the principles and tactics we use so you get modern convenience without handing over the keys to your house.

Principles we won’t compromise

Minimum data, maximum value. Local control for safety functions. Transparent logs. Updateable systems. These aren’t slogans—they’re design constraints.

If a feature requires cloud, we ask: what happens during an outage? Can a local fallback keep essentials running? Asking that early improves the system immediately.

Edge hubs and why they matter

An on-prem controller keeps scenes, credentials, and schedules available during outages. It also reduces round-trip latency and avoids spraying data across third-party clouds.

Edge makes experimentation safer: test new routines locally, then decide what—if anything—needs remote access.

Accounts, keys, and guests

Use per-person accounts with roles, not shared logins. Time-limit guest access. Back up keys offline. If you change phones, your house shouldn’t forget you.

QR-based onboarding with expiry beats texting passwords. You’ll be more generous with access when revoking it is effortless.

Network segmentation in plain English

Put cameras on an isolated VLAN, block cross-talk, and forward only what’s needed to the controller. Your TV doesn’t need to see your nursery cam.

Simple rule: if a device doesn’t need to talk to other devices, put it on a ‘controller-only’ island. Fewer conversations, fewer surprises.

  • Strong DNS, DoT/DoH where appropriate
  • Turn off UPnP unless explicitly required
  • Auto-patch the edge hub on a maintenance window

Trade-offs and how we handle them

Voice assistants and remote control imply some cloud. We prefer multi-admin Matter so you can use voice without giving cloud services the keys to everything.

When cloud is useful, pick services with local fallbacks and granular permissions. The aim is choice, not purism.