Cast your mind back to October 2025, specifically October 20th. You might remember that Amazon Web Services went dark for 15 hours, caused by a DNS configuration error in a Virginia data center that cascaded across roughly 1,000 platforms. When those servers became unresponsive, millions of smart homes did alongside them. Alexa stopped responding, Ring doorbells went offline, and even Eight Sleep "smart beds" lost their temperature regulation and overheated, jolting users awake in the middle of the night. It was a sobering reminder that for most people, the word "smart" in smart home comes with one essential requirement: an internet connection.

During that outage, my smart home kept running like nothing happened. My lights still worked, my automations continued, and my bed still functioned normally. That last part is more because I find the concept of a "smart bed" somewhat incredulous; it epitomizes the stereotype that many with a smart home are often tarred with unfairly. For everything that kept working in my home, the difference wasn't that I had better hardware or a more expensive setup, it was thanks to a single open-source application called Home Assistant.

The cloud holds your smart home back

Why do servers hundreds or even thousands of miles away have to get involved?

Here's the frustrating secret of the modern smart home, one that to this day I think not everyone is aware of: most of your devices don't actually do their thinking at home. When you ask Alexa to turn off a light, that voice command travels to Amazon's cloud servers, gets processed, and a command is sent back to your bulb. That round trip isn't instantaneous, and it can take as long as one to three seconds on a good day.

That model is relatively simplistic for an end user to understand and work with, but it introduces multiple failure points. There's your local equipment, your internet connection, and the manufacturer's cloud infrastructure. If one of those fail, your "smart" light becomes an expensive dumb light that you mightn't even be able to turn on.

That aforementioned AWS outage wasn't an isolated incident, either. In June 2025, Sengled's cloud went down for multiple days straight, leaving thousands of users unable to control their smart bulbs. Even something as simple as a smart DVR can cause issues, too. Tablo owners have faced multiple outages, and complaints are extremely common. When that happens, users can't play back recorded TV or even watch live broadcasts because their over-the-air DVRs depended on cloud servers to function.

It's not just the smaller providers that have issues, either; Ring and Blink had their own service interruptions throughout the year. Cloud-dependent smart homes are only as reliable as the weakest link in a very long chain, and many of those links in the chain aren't as robust as you might hope.

Home Assistant is different

Giving users back control

Home Assistant is an open-source home automation platform that takes a completely different approach. Everything runs locally, on hardware sitting in your house. Your automations, device states, dashboards, and integrations are all processed on-device. No data gets sent to or stored in some company's cloud unless you want it to. And when your internet goes down, Home Assistant still chugs along happily.

Home Assistant is different because it communicates directly with smart devices over local protocols like Zigbee, Z-Wave, Thread, Matter, Wi-Fi, and Bluetooth. It only falls back to cloud communication in circumstances where a user has set it up to do exactly that, but the default is a local-first experience. Response times sit around 0.2 to 0.4 seconds, compared to the one to three seconds you'd wait with a cloud-dependent system, and that's with the self-hosted voice processing that it natively supports. That speed difference is primarily thanks to the fact that with a cloud-first smart home, you're waiting for permission from a server farm in Virginia for something as simple as a request to turn a light bulb off.

Home Assistant hit two million active installations worldwide as of May 2025, doubling from one million in a single year. I can see why as well, as it's enabled me to link up all of my devices to one unified platform, and that includes anything from my smart phone to an ePaper display. GitHub called it "one of the most active, culturally important, and technically demanding open source ecosystems on the planet" in a December 2025 feature. It's governed by the Open Home Foundation, a non-profit focused on privacy, user choice, and long-term device sustainability.

How local control actually works

There are a ton of options

Home Assistant's reliability comes down to protocols that don't need the internet to function. The first two are Zigbee and Z-Wave, which are mesh networking protocols that have been staples of home automation for years. Zigbee devices talk to each other and to a USB coordinator plugged into your Home Assistant hardware, forming a mesh network that strengthens as you add more devices. Z-Wave operates on a different frequency band, so it doesn't compete with your Wi-Fi for airtime. Both are entirely local, with no cloud server involved at any point.

Matter and Thread are two newer protocols that are often referred to interchangeably, but that isn't quite accurate. Thread is a low-power, IPv6-based mesh networking protocol designed for constrained devices. It can coexist with Zigbee on multi-protocol 802.15.4 adapters, such as the Home Assistant Connect ZBT-2, which launched in November 2025, though the two operate as entirely separate networks and, on that particular device, you pick one or the other, not both.

Matter, meanwhile, is an application-layer smart home standard that runs over Thread, Wi-Fi, or Ethernet. Home Assistant became a fully certified Matter controller through the Connectivity Standards Alliance in 2025. Matter-compatible devices can be controlled locally without a mandatory manufacturer cloud, though some vendors may still offer optional cloud services. In short, Thread provides one of the underlying connectivity layers, while Matter defines how devices communicate on top of it.

ESPHome deserves a mention here, too. ESPHome is a firmware framework for inexpensive ESP32 and ESP8266 microcontrollers that lets you build custom local sensors and devices. Want a temperature sensor in your garage? A plant moisture monitor? A custom LED controller? ESPHome lets you build it for a few dollars in parts, and it communicates with Home Assistant entirely over your local network. Sensors are defined using YAML, so a temperature sensor might only be approximately four lines of code.

None of these protocols require your router to be connected to the internet. They work on your local network. You can even ditch the cloud for voice assistants, using the Wyoming protocol alongside Whisper for speech-to-text and Piper for text-to-speech. Mine is powered by a local LLM and sounds like GLaDOS, and you can control your entire smart home with voice commands that never leave your local network if you like.

There are downsides, of course

You build it yourself

It's not all sunshine and roses, and I'd be doing a disservice if I didn't mention the downsides of taking the plunge and opting to manage your smart home yourself. Home Assistant may be a user-friendly application as a whole, but it still has a learning curve. Setting up a new installation from scratch takes real time, especially if you're configuring Zigbee coordinators, building automations, and organizing your dashboard. It's more involved than plugging in an Echo and downloading the Alexa app.

You also need to be intentional about your device choices. Not every smart device works locally. If you've already invested heavily in cloud-only ecosystems, migrating to a local-first setup probably means replacing some hardware. That said, Home Assistant can often coexist with cloud devices. It'll control them when the internet is up and gracefully handle the ones that go offline when it's not. Some devices can be converted to local-only control; for example, my Tuya light bulbs still work without the cloud, thanks to the Tuya Local integration.

Remote access is another consideration. A local-first system doesn't talk to the internet by definition, which means you can't control your home remotely without some extra setup. Home Assistant offers Nabu Casa, a paid cloud subscription that provides secure remote access, or you can configure a VPN for free. Either way, it's opt-in rather than the default.

Also, don't forget about power outages. Your internet going down is one thing, but if the power goes out too, your Home Assistant hub goes with it. This isn't the end of the world as when your power goes out, you probably don't have light bulbs to use in the first place, but it's something to be aware of.

It's more than just convenience, though

Privacy and control are both important

The October 2025 AWS outage wasn't just an inconvenience to end-users, and the consequences extend well beyond a few hours of downtime. Ring doorbells going offline meant home security systems failed, and cloud-dependent devices became unresponsive. When your home's basic functions, like security, lighting, and climate control, depend on a company's server uptime, you've handed over control of your living space to a third party.

That's why I like Home Assistant. It puts that control back in your hands, and more importantly, your data stays on your hardware. Your automations run on your schedule. No company can decide to sunset a product and brick your setup overnight, which seems to be happening more and more as of late.

But local control isn't just about reliability; it's also about privacy. The privacy argument is one that is often misunderstood by those who denigrate the concept of the smart home, and it's important to address it.

Your data is worth something, and we know that because companies are willing to pay for it. Let's say a company introduces a new "loyalty" scheme, where you can scan a card to get exclusive deals. That company then purchases data from a smart home provider, gathering data on usage habits. Now the original company has data that combines demographics with assumed sleeping patterns, based on activity data, light usage, or other metrics, and can even infer some of the products you may use daily thanks to the hardware you have integrated.

If that combined data signals that you're more likely to buy a particular product than other demographics, and it's a product you'd buy regardless of a price bump, the company knows it can raise the cost for no other reason than to increase its profit margin. And that process was simplified by data collection from smart homes.

The Open Home Foundation's mission is straightforward and addresses all of the above scenarios: your data is yours, there should be no vendor lock-in, and devices should be built to last. To their credit, so far, their mission has been largely successful. My smart home doesn't care about cloud outages, there's no risk of a device being sunset, and my ISP is irrelevant to the conversation. My Home Assistant instance runs in a virtual machine on Proxmox, but you can just as easily deploy it on an old laptop, mini PC, or even a Raspberry Pi.

If the smart home industry's repeated cloud failures have taught us anything, it's that local control isn't a niche preference. It's the only architecture that makes sense for something as basic as your home. The technology is mature, the hardware is affordable, and the community is thriving. If you've been on the fence, now's a good time to give it a try.