Build vs Buy Real-Time Infrastructure

The build versus buy question for real-time infrastructure has a cleaner answer than most: buy the backend, build the product. The reason is that the real-time layer is a set of hard, generic guarantees that are identical across every app, and the product is the part that is actually yours. Teams that invert this spend a year building a mediocre real-time backend and ship a worse product for it.

I run a portfolio of ventures and I own a lot of my own stack. So when I say buy here, it is not because I am afraid of infrastructure. It is because I have priced this specific build, and the math is rarely close.

What building real-time actually costs

People estimate the cost of a real-time backend by looking at the socket layer, which is the cheap part. A WebSocket library is a weekend. The expensive part is everything around it.

You need a pub/sub backbone so messages cross nodes. A presence system with heartbeats and expiring state so the online list is not full of ghosts. Message durability so a client that blinks offline does not silently lose data. Per-message authorization because a long-lived socket is a long-lived attack surface. Backpressure so one slow client cannot take down a node. Graceful deploys so shipping code does not drop every session. And reconnection logic with backoff so clients do not stampede back at once.

Each of those is a real project. Together they are a distributed system, and distributed systems fail in intermittent, load-dependent ways that are miserable to debug. I wrote out the specific failures in the real-time backend mistakes that break apps at scale. The true cost of building is not the initial code. It is the on-call rotation you sign up for permanently.

What buying actually costs

Buying is not free either, and pretending otherwise is how people get burned. A managed real-time backend costs money that scales with usage, and it puts a dependency between you and someone else's platform.

The honest risks are lock-in, pricing that climbs as you grow, and the loss of some control over how the system behaves. These are the same concerns I take seriously about managed cloud in general. If the provider's model does not fit your traffic, you can end up paying for a shape that does not match yours.

So the buy decision is not automatic. It is a bet that the provider's guarantees are better than the ones you would build, and that the price is less than the fully loaded cost of building and operating your own, including the engineers you would tie up forever.

Where buying clearly wins

Buying wins when the real-time layer is not your differentiator, which is almost always. Your users do not choose you because your presence heartbeat is elegant. They choose you for the product. Every engineering hour you spend perfecting reconnection logic is an hour not spent on the thing customers pay for.

Buying also wins on time to survive load. A mature real-time backend has already met production traffic. Yours has not. Shipping on infrastructure that has already survived load beats shipping on infrastructure about to meet it for the first time, in front of your customers.

The exception is when real-time genuinely is your product. If you are selling the infrastructure itself, you build it, because it is the thing. For everyone else, the guarantees are generic and the smart move is to rent them.

How I actually decide

My rule is simple. Own the layers that are strategic and rent the layers that are merely necessary. I own my hosting and my data pipelines because control there is a real advantage, which is the case I make in self-host versus managed cloud. But the real-time guarantees are the same for every product, so I would rather stand on one hardened backend than rebuild the same distributed system per venture.

That is the entire thesis behind AltoHost: a complete real-time backend that owns the connection lifecycle, delivery, presence, and scale as one set of guarantees, so the product team assumes them instead of assembling them. Build the app. Buy the backend it stands on.

Closing

Build versus buy is not a question of pride. It is a question of where your advantage actually lives. Real-time infrastructure is hard, generic, and identical across products, which makes it the textbook thing to buy. Spend your build budget on the product only you can make, and let the backend be someone's whole job instead of your side quest.