Runtime type assertion at the edges is mostly solved through `zod` and tools like `ts-rest` and `trpc` makes it so much easier to do full-stack Typescript these days.
ESM modules just work with both Node and Typescript, Node can run .ts files, and there's the a good enough test runner built in. --watch. The better built in packages - `node:fs/promises` - are nice with top-level await for easier async loops.
It took a while to convince everyone involved to just be pragmatic, but it's nice now.
trpc and ts-rest are a different animal in my opinion. I'm happy to use either one but won't deal with them in production. For trpc that's mainly due to the lack of owning API URLs and being able to more clearly manage deprecating old URLs gracefully.
For ts-rest I just tend to prefer owning that setup myself, usually with zod and shared typings for API request/response pairs. It also does irk me every time I import what is clearly an RPC tool named "-rest"
Two types of languages...
That leads me to ask, what about project dependencies? I wrote a lib for my data models in typescript and I want to import that into my app in node, in typescript? Does the rule only apply to npm packages? There’s opportunity here…
I wrote a runtime in golang that runs typescript (well, JavaScript in general). The grafana folks have sobek that all they need is to add type striping. I feel like if there’s one runtime where typescript could be adopted fully and it would change the world is Node.js. No transpiler, no typescript-go, no rust (well, maybe some rust ;) just a great parser that will keep track of the source map and types in debug mode (for tracing).
Either way, kudos to the node team, contributors, for pulling in the goal posts to make the kick to launch shorter. I’m still a fan of bun, and my own runtime, but node is the standard by which we all are kinda following. I also like that the embedding api is simple and clean to use now so if you want to make an executable, you can.
[0] https://nodejs.org/api/typescript.html#type-stripping-in-dep...
"To discourage package authors from publishing packages written in TypeScript"
I tried to use it with private packages but that doesn't work either, apparently node doesn't even read the "private" field.
"You publish TypeScript source, and JSR handles generating API docs, .d.ts files, and transpiling your code for cross-runtime compatibility."
Still would have been nice to have this for private packages.
This makes Deno/Bun much more attractive alternatives
Last actually note-worthy improvement I heard of was properly supporting import/export (although do you still need to use the .mjs hack?), but I've been out of the loop here for sometime so would be nice to know what they've added since.
https://kashw1n.com/blog/nodejs-2025/
It doesn’t cover everything, but as an old-school Node user I found several interesting features I didn’t know about.
Syntax detection is enabled by default in v22.7.0, v20.19.0:
https://nodejs.org/api/packages.html#syntax-detection
Sounds like the obvious correct solution, making .cjs and .mjs obsolete - unless of course someone uses import() statements exclusively, in which case I need to ask: why?
And the biggest issue with Node IMO is that the standard lib still forces you to rely on endless npm dependencies.
Node is still very much stuck.
How? We have async/await file access, a async/await test runner, and even async/await sleep built in. What are you missing?
On the projects I am involved, they could even not exist, only node LTS releases matter, and the most recent projects are still node 20.
You couldn’t phrase your original question as a statement “Them have though.” That’s often a quick test for valid English grammar. With the correct pronoun, it makes more sense: “They have though.”
As another example, take this sentence: “Have you seen them though?”
“You” is the subject of that sentence, and “them” is the object.
I know I’m just a single data point but I’ve had a lot of success migrating old node projects to bun (in fact I haven’t used node itself since Bun was made public)
Again, I might be saying something terribly stupid because JS/TS isn’t really my turf so please let me know if I’m missing something.
Node has its share of flaws, but it's the de facto baseline against which things are tested and developed. I'm somewhat more comfortable working with The Main Thing.
The JavaScript ecosystem is nightmarish enough that many developers don't want to switch to the Next Cool Thing. I think many of us have had enough fatigue caused by new build tools, new bundlers, new runtimes, etc.
As of right now, Bun is not compelling enough for the potential headaches down the line.
(Maybe there won't be any, but I've spent weeks dealing with incompatibilities caused by a single TS minor update (which should've been breaking). Days chasing after dependency problems, after missing docs, etc.)
Because Node is controlled by and maintained via the OpenJS Foundation. Bun is a venture-backed startup. That would be fine, but multiple, direct requests from me to the founder (Jared) about what the business model is (what I personally need to say "yes" or "no") have gone without response every time.
That led me to the assumption that Bun may very well be technically superior (or at least on the track to being so), but I can't bet anything significant or long-term on it. I need to know that this isn't just an exit vehicle for the founder (masquerading as a desire to fix JS server runtimes). Silence to a simple (dare I say, obvious) question doesn't bode well.
localAddress on TCP connections ignored, last time I tried it its no-op
Incompatibility with Node module APIs (https://github.com/spamscanner/spamscanner wouldn't work)
EventEmitter race problems (partially worked around with https://www.npmjs.com/package/eventemitter2)
Svelte vites dev server sometimes forever freeze until I wiped node_modules and reinstalled it.
I'm waiting patiently for bun to catch up because I would love to switch but I don't think its ready for production use in larger projects yet. Even when things work, a lot of the bun-specific functionality sounds nice at first but feels like an afterthought in practice, and the documentation is far from the quality of node.js
Really, in the Node ecosystem you eventually learn not to put all your eggs in one basket. Different things excel in different aspects. Here is my preferred setup for now:
Bun.js: As a Node runtime, and for TS execution and test running. I tried lots: TSX, TS-Node, Node itself
NPM For executing tooling scripts
PNPM For installing dependencies. It's simply better than the rest (npm, yarn, bun) for several reasons
Biome.js For linting (superior to every other tool I tried)
But really, any test runner is beter than Node's: that thing is awful. It's like they looked at all the test runners in existence, and instead of copying what they all did, decided "let's make things harder for no apparent reason."
Why would you switch from runtime A to runtime B? I mean, you presented no reason at all, let alone a compelling one, to pick either one. So what leads you to believe it is a reasonable idea to waste time switching runtimes?
I dislike being on the bleeding edge for things. NodeJS is the most supported in the JS ecosystem. I find it much better to just be on the "default" option for things. You know, choose boring technology.
Is it a boring technology? I remember trying Node.js when it just came out, and I don't think all that much improved. Whole node.js always felt one step forward, two steps back. A lot of early design decisions still hurt it.
I would call it stagnated before I call it boring.
The best way to do this atm. is using (and configuring) yarn for zero-installs.
This keeps dependencies inside the codebase so that: * Issues can be easily traced to the code that actually ran - development and deployment are the same. * Deployment doesn't depend on package repositories. * Deployment is secure from many kinds of attacks. * It is possible to transparently patch packages. * Development is only internet dependent when adding a new package. * and the best ease-of-use - no reinstall when changing branches.
Simple example: you know how at the command line you can type "npm run", and then type a character or two, hit tab, and the appropriate script from your `package.json` will autocomplete? And if you keep going (eg. "npm run knex") you can do the same thing to autocomplete arguments?
Bun still hasn't figured out how to do that (https://github.com/oven-sh/bun/issues/6037), even though they can all but copy NPM's (already written) completions. I really liked using bun when I played around with it (and it ran my codebase perfectly, without issue) ... but if they can't handle something as simple as Bash completions, they're clearly not ready for the big leagues.
Not supporting type stripping in node_modules is unfortunate
Writing a library in TypeScript (with typechecks in CI/CD as devDependencies) and just importing it directly from Node.js...
It might finally be time to switch to Deno or Bun =(
Very well done Node team!
You can run a typechecker (such as tsc) that check various properties of your code statically, relying on the type information. It is then erased.
The same applies, say, to Python: type annotations are ignored at runtime. Somehow similarly, Java's type information is also partly erased in the bytecode; in particular, all the information about parametrized types. (This is to say nothing about actual machine code.)
Except for where it does: Enums, namespaces, parameter properties, etc.
Just for generics, I believe
That's a bit misleading. Node being able to run TS code does not "improve safety", because that's not where the type checking happens. You can do type checking in your editor, or various other points in your toolchain.
Node being able to run TS code reduces the friction in writing TS code, which indirectly helps with type safety.
That just doesn't make sense. Yes, you can wait for your editor in your current open file, if you are lucky and the change in the open file doesn't break anything downstream in another file that is not yet open. In best case you have such simple code that nothing breaks, and in worst case, you have to still run it with type-checking - on top of running it in type-stripping-mode, because you got weird errors in runtime. This is a net negative.
This whole situation is there because we are trying to workaround the slow TSC. It's not a feature, it's something we actively work around. We try to whitewash now the obviously less useful "solution" of running code without its core features enabled: type checking. To me this is insane.
I agree that it's better to think of Typescript as a linter that needs specialised annotations to work, rather than a type system like you might find in Java or Rust.
What, pray tell, would be the point of putting all that type information in there, and then have it checked (via tsc), if not for the sake of safety? What other use would this have in your opinion?
that's exactly the point--GP is pointing out that node can't do that part
I think running TS without type checks is almost entirely pointless.
To check types at runtime (if that can even be done in a useful way?) it would have to be built into v8, and I suppose that would be a whole rewrite.
https://dev.to/ivanzm123/dont-use-enums-in-typescript-they-a...
They added an optional flag to disable enums (and a few other features) in 5.8
I suspect this would only handle the most rudimentary and basic typescript files. Once you start using the type system more extensively I suspect this will blow-up in your face.
It's kinda a shame. What a missed opportunity to do it properly (rather than relying on third party plugins etc)
Edit: if you are just using typescript for type checking at build time (i.e. the most basic rudimentary typescript files) the sure fine this may help you. But typescript also generates JavaScript code for missing features e.g. proper class access modifiers, generics, interfaces, type aliases, enums, decorators etc etc. typescript generates JS code to handle all that, so you're going to have a bad time if node just replaces it with the space character at run time.
Source: 49m 43s https://m.youtube.com/watch?v=NrEW7F2WCNA
Of course, everyone else is free to use enums, decorators, class parameters, etc., but for quick prototyping or writing simple scripts in TypeScript, Bun has been good enough for me, and I assume Node will be "good enough" as well.
[1] https://www.typescriptlang.org/docs/handbook/release-notes/t...
That’s what all the other tools like ts-node and tsx do already.
I’m not sure what more are you expecting to do?
Typescript is build time type checked, there is no runtime component to TypeScript. If you want type checking you run tsc.
I think this is a great step in the right direction by node. It will save transpiration on the server and improve stack traves and whatnot.
> Once you start using the type system more extensively I suspect this will blow-up in your face.
I don’t see why. There isn’t any more runtime information in “complex” TypeSceipt types than in simple ones. It’s all build time - see above.
> What a missed opportunity to do it properly
Please explain in more detail what “doing it properly” means to you. Including the typechecker? If so that wouldn’t make sense - they would be competing with TypeScript itself, they shouldn’t, all the “third party plugins” rely on tsc for type checking.
You’re downplaying this quite a bit. Node being able to execute TS files slashes a lot of tooling in half, especially during development when you want to modify files and retry in quick succession.
Besides, I’m not so sure this cannot be expanded in the future to adopt validation features before stripping the type information. For now it solves some major pain points for a lot of people.
Remember ESM fiasco? Now we have a few years of that all over again, this time with different versions of TypeScript, settings, and tsgo. Good news!
esm actually caused errors so there should not be any issues here
This lets you build simple web apps (i.e., those with no frontend dependencies) as pure TypeScript, including the frontend, by stripping the types out from your frontend scripts as you serve them: https://github.com/bakkot/buildless-ts-webapp
Just converted many of services to TS and some are WIP. It’s a big win.
This will unfortunately drive people towards using TS only as a linter, and not use its powerful features that are inherently impossible to implement with just type stripping.
As a personal taste I don’t really like decorators that much, but it’s true that nestjs projects (which is probably a majority of new backend TS projects) will not gain anything from this release. Then again, you always set nestjs up with a template anyway that has all of the tooling and building baked in. So whatevs.
It’s still a huge huge win, and I finally have hope for typescript-ifying some horrible legacy node apps at work!!
This is a really neat idea and I hope typescript adds this as a compiler option.
These are packages using ts-node or tsx to run typescript in node, and with node 22.18 they seem to be using nodes native typescript support instead, and failing due to its limited feature set, or subtly different module resolution.
I’ve always just run tsc to a .gitignored’d directory and execute my JS from there.
Edit: Thanks for the responses. There’s some great examples in there!
As a note, Node has a built in --watch now, too
TypeScript is for compile time checking of a language that was not designed to have them. Runtime types have very different requirements! It has to be in the language from the early design phase, otherwise it will just be a hack with many conditions, restrictions and holes.
TS Types are only partially a description of the underlying types in the code, a very big part instead is that it provides guard rails that prevent you from using a lot of perfectly fine and valid JS code that would however be incompatible with type guarantees. You pay the price of using only a part of the large space of JS code possibilities for guarantees. If you were to put that into the runtime you would end up with two different versions of the language. If you still want to support the full JS you would end with two runtimes in one (or one that has so many branches and conditions that maintaining that runtime is a real beast).
Now of course, this would only add type syntax to the language, not true processing: there's nothing in the spec about actually handling them. Still, it's a step in that direction, so I wouldn't say "very unlikely to ever happen" ... "still a long ways off (if ever)" would be more accurate.
Only downside I see is that It can slow down the code as the runtime now has to evaluate type level functions in order to know what to place in the metadata.
But you're right in the sense that it has to go into the core ECMA specification rather then being a node project.
typescript is pretty ambiguous about a lot of the things that would need explicit definition for runtime safety, and anyways we already have tools for that - it’s called zod.
and comprehensive checks would incur a significant runtime penalty, unless they were restricted to external interfaces, which is what you’re really concerned about. we already have tools for that - protobuf, swagger, etc.
anything else is sharing a runtime with you. so either it’s in your ide, and you just don’t write shitty code; or you’re trapped in some kind of demonic javascript prisoner’s dilemma, and you are mutable.
so typescript is basically ‘good enough’ for developers.
thinking forward anyway, and assuming you’re really willing to share a runtime with a stranger…
node doesn’t really operate in that kind of context, but maybe browser code does. i could imagine a framework based on web components, workers, and maybe iframes, taking advantage of message boundaries to enhance analysis and conceal code generation. it’s not that much better than typescript.
but if you want efficient runtime checks, and you want to leverage static analysis and strong module boundaries to scope the type-checking codegen, and you probably need additional syntax, you might as well target wasm.
Caveat is that there are some restrictions with the compiler and some possible footguns (duplicated declarations bloating code).
Fastify, NestJS (bleh), Koa, Hono are the modern replacements for express, none of them have caught on as a standard though. My personal favorite for small projects is Polka (https://github.com/lukeed/polka), when I'm not using Go instead.
And do mean everything: I run an entire Postrgraphile server through Next (and you can easily do the sme with Supabase or a similar tool)!
all threads saying the truth, js on the server could implement actual ts and not yet another transpiler gets downvoted.
js "experts" think they are smarter because they know ts is just annotations for a linter. they don't even question why that is so and why that sucks.
