I agree.

Didn't get far enough along to understand the motivations and considered alternatives.

Didn't get far enough along to understand the motivations and considered alternatives.

OpenNext does model [0] incremental static regeneration, but beyond that I actually don't know, or at least don't recall. OpenNext doesn't do per-route lambdas like vercel does, so it's not like you get any behavior differences there.

I _think_ you can get scale to zero on Lambda by deploying a docker container, too.

[0] https://opennext.js.org/aws/v2/advanced/architecture

1) I don't think it's related to Next, per se, but there may be behavior I didn't build the expertise to comment on. I also know that there were major inefficiencies in the application, so, for example, our P90 latency was (imo) terrible.

2) We'd have to define what constitutes low traffic vs any other arbitrary measure, so it's moot to discuss like this; all I said it wasn't high traffic. You could run it for cheaper, but there wasn't much expertise for self-hosting, for example.

3) For all I remember it may have been half that in daily cost. In any case, miniscule compared to engineer time. What was worse was the prior decision to use serverless aurora rds, that dwarfed everything else in AWS cost - I know this is tangentially related, just saying optimizing that a bit more was not the highest priority, we could do it for cheaper.

It offers packaging for deploying to a serverless environment (e.g. Lambda) analogous to how Vercel does it.

The last question is salient, and it's possible for OpenNext to break and have to catch up to changes in Next.js, though I believe there's some more direct collaboration. I'd say that's the biggest downside - it's not guaranteed compatibility.

I did a migration recently (comments elsewhere in this post), and I don't recall the specific issue, but I _do_ recall running into at least one scenario where OpenNext had made a decision that impacted - in a way that was visible to me and undesirable - how Next.js functioned. That's not a criticism, there's tradeoffs.

OpenNext is just for packaging the Next.js build artifacts. The infrastructure is defined by projects that deploy those artifacts, examples here: https://opennext.js.org/aws/get_started

Some of them are, for example, Terraform projects that list the specific infra. I have experience with the SST deployment, whose website unfortunately doesn't do a great job of listing the infra architecture.

The biggest cost for us on Vercel (several hundred dollars a month) was Image Optimization, and that was because the app was being majorly inefficient with images, in part due to some default behavior in Next.js that we found unfriendly [0], and in part due to negligence. That being said, it wasn't "cheap" by any means outside of that, still hundreds a month for something that I would not consider a high traffic application (I wish I could remember more specific numbers).

Migrating to OpenNext using SST, I think we got the bills for compute and asset serving down to like $15/day or something (granted, we spent expensive engineer time on the migration).

[0] https://nextjs.org/docs/app/api-reference/components/image#s...

In the company I just left, I actually went through the process two or so months ago of migrating their Vercel deployment to AWS. I evaluated several options that are listed on the website and on GitHub, and we landed on using OpenNext via SST, it was a low-pain effort, especially given the CTO's desire to also migrate off of Next.js.

As other commenters have touched on - my understanding is the purpose of OpenNext is to package the output artifacts of a Next build in a way that can be deployed to a serverless environment, analogous to how Vercel does it. The supporting projects like SST and the other links in the repo are to take those OpenNext artifacts and deploy them to infrastructure generally in an opinionated way - additionally supporting some of the "extra" features described in the repository.

The last project I was working on was to then migrate from SST to Fargate, as a persistent process (serverful?) deployment was preferable for various reasons. In that scenario, we would just be running the built in server using the Next.js standalone deployment mode (effectively a `node index.js`). We didn't need the extra functionality covered by OpenNext.