Make Any TypeScript Function Durable

Of all the syntax options they could've gone with, they settled on what I would say is arguably the worst. If you want a one-liner, decorators are widely used across different languages and Typescript supports them as well.

So vercel is adamant on making nextjs apps behavior completely unpredictable and hidden behind tons of magic code?

At least in any other framework library I can just command click and see why things are not working, place breakpoints and even modify code.

So this seems similar to https://temporal.io/, am I reading this right? I used that briefly a few years ago and it was pretty nice at the time. It did make some features much easier to model like their welcome email example. Would love to hear from someone with extensive temporal experience, iirc the only drawback was on the infra side of things.

This seems pretty similar to Cloudflare Workflows (https://developers.cloudflare.com/workflows/), but with code-rewriting to use syntax magic (functions annotated with "use workflow" and "use step") instead of Cloudflare's `step.do` and `step.sleep` function calls. (I think I lightly prefer Cloudflare's model for not relying on a code-rewriting step, partly because I think it's easier for programmers to see what's going on in the system.) Workflow's Hooks are similar to Cloudflare's `step.waitForEvent` + `instance.sendEvent`. It's kind of exciting to see this programming model get more popular. I wonder if the ecosystem can evolve into a standardized model.

So at it's core this is "just" a toolkit to add automatic retries to functions inside another function? I don't know if the audience Vercel is targetig knows about idempotency as well as they should before plastering all their functions with "use workflow".

I guess in the end it's another abstraction layer for queues or state machines and another way to lock you into Vercel.

This is actually pretty cool. We have a similar custom library at Xbox that's used extensively across all of our services.

I do wish that there was some kind of self-hostable World implementation at launch. If other PAAS providers jump onto this, I could see this sticking around.

I'd rather be explicit about what's going on at each step. That way idempotent functions can be handled differently, retry limits can be applied, and no separate preprocessor is required.

    export async function welcome(userId: string) {
      const user = await retry(() => getUser(userId));
      const { subject, body } = await retry(() => generateEmail({
        name: user.name, plan: user.plan
      }));
      const { status } = await retry(() => sendEmail({
        to: user.email,
        subject,
        body,
      }), 2);
      return { status, subject, body };
    }

"use turnMyBrainOff";

"use blackBoxWrapperForEverything";

Am I stupid, or does the page not actually explain that workflow is?

Use client and use server aren’t great, but the fact they had to be declared at the top of a file was at least clear.

Starting to scatter magic strings throughout a code base feels like a real step back.

Somewhat related since this about "workflows" and not cloud function, but are there any practical benefits to cloud functions other than the fact that it's cheaper for the providers as they don't have to run an entire bespoke runtime for every customer/application?

can anyone point to the "Durable" part?

looking at the docs and examples, I see Workflows and Steps and Retries, but I don't see any Durable yet. none of the examples really make it clear how or where anything gets stored