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Phoenix.new – Remote AI Runtime for Phoenix

639 points| wut42 | 8 months ago |fly.io

272 comments

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colecut|8 months ago

I am a long time php dev who has been interested in learning elixir/phoenix for a while but never quite motivated enough.

I saw this and thought, if this doesn't get me to give it a go, nothing will.

Less than 45 minutes after signing up for fly.io, I have a multi-room tic tac toe game deployed.

https://tic-tac-toe-cyber.fly.dev/

I had it build the game, opting for a single room at first to see if that worked. Then I had it add multiple rooms on a different git branch in case that didn't work. It worked great.

I learned very little about elixir, phoenix, or deploying to fly.io up to this point, and I already have a nice looking app deployed and running.

I know a lot of devs will hate that this is possible, and it is up to me now to look at the steps it took to create this and really understand what is happening, which are broken down extremely simply for me...

I will do this because I want to learn. I bet a lot of people won't bother to do that. But those people never would have had apps in the first place and now they can. If they are creating fun experiences and not banking apps, I think that is still great.

You guys have been releasing amazing things for years only to be poorly replicated in other languages years later.. but you really outdid yourselves here.

I'm blown away.

edit: is there a way to see how much of my credits were used by building this?

chrismccord|8 months ago

This is amazing on multiple fronts! I reset your usage, so the next round is on us! We shipped credits the day before launch, so usage UI is still TBD, but should be out next week. Thanks for the sharing your experience!

jonahx|8 months ago

Was the graphic design created from prompts too? It's surprisingly nice, especially considering you spent 45 minutes on it.

curiouser3|8 months ago

Did you figure out how much credit was used? I want to try this out, but $20 of credit can go quick doing agentic work

chrismccord|8 months ago

Phoenix creator here. I'm happy to answer any questions about this! Also worth noting that phoenix.new is a global Elixir cluster that spans the planet. If you sign up in Australia, you get an IDE and agent placed in Sydney.

tiffanyh|8 months ago

Amazing work.

Just a clarifying question since I'm confused by the branding use of "Phoenix.new" (since I associate "Phoenix" as a web framework for Elixir apps but this seems to be a lot more than that).

- Is "Phoenix.new" an IDE?

- Is "Phoenix.new" ... AI to help you create an app using the Phoenix web framework for Elixir?

- Does "Phoenix.new" require the app to be hosted/deployed on Fly.io? If that's the case, maybe a naming like "phoenix.flyio.new" would be better and extensible for any type of service Fly.io helps in deployment - Phoenix/Elixir being one)

- Is it all 3 above?

And how does this compare to Tidewave.ai (created as presumably you know, by Elixir creator)

Apologies if I'm possibility conflating topics here.

joevandyk|8 months ago

The Phoenix.new environment includes a headless Chrome browser that our agent knows how to drive. Prompt it to add a front-end feature to your application, and it won’t just sketch the code out and make sure it compiles and lints. It’ll pull the app up itself and poke at the UI, simultaneously looking at the page content, JavaScript state, and server-side logs.

Is it possible to get that headless Chrome browser + agent working locally? With something like Cursor?

troupo|8 months ago

I know it's early days, but here's a must-have wish list for me:

- ability to run locally somehow. I have my own IDE, tools etc. Browser IDEs are definitely not something I use willingly.

- ability to get all code, and deploy it myself, anywhere

---

Edit: forgot to add. I like that every video in Elixir/Phoenix space is the spiritual successor to "15-minute rails blog" from 20 year ago. No marketing bullshit, just people actually using the stuff they build.

pmarreck|8 months ago

Include optional default email, auth, analytics, job management (you know… the one everyone uses ::cough:: Oban ::cough::), dev/staging/prod modes (with “deployment” or something akin to CD… I know it’s already in the cloud, but you know what I mean) and some kind of non-ephemeral disk storage, maybe even domain management… and this will slay. Base44 just got bought for $80M for supplying all those, but nothing is as cool as Elixir of course!

These other details that are not “just coding” are always the biggest actual impediments to “showing your work”. Thanks for making this!! Somehow I am only just discovering it (toddler kid robbing my “learning tech by osmosis” time… a phenomenon I believe you are also currently familiar with, lol)

Snakes3727|8 months ago

Hi just to confirm as I cannot find anything related to security or your use of using submitted code for training purposes. Where is your security policies with regards to that.

krts-|8 months ago

Is there a transparent way to see credit used/remaining/topped up, and do you have any tips for how you can prompt the agent that might offer more effective use of credits?

The LLM chat taps out but I can't find a remaining balance on the fly.io dashboard to gauge how I'm using it. I _can_ see a total value of purchased top ups, but I'm not clear how much credit was included in the subscription.

It's very addictive (because it is awesome!) but I've topped up a couple of times now on a small project. The amount of work I can get out the agent per top-up does seem to be diminishing quite quickly, presumably as the context size increases.

burnt-resistor|8 months ago

Is there something comparable that works similarly but completely offline with appropriate hardware? Not everywhere has internet or trusts remote execution and data storage.

PS: Why can't I get IEx to have working command-line history and editing? ;-P

mrdoops|8 months ago

Any takeaways on using Fly APIs for provisioning isolated environments? I'm looking into doing something similar to Phoenix.new but for a low-code server-less workflow system.

miki123211|8 months ago

1. What's your approach to accessibility? Do you test accessibility of the phoenix.new UI? Considering that many people effectively use Phoenix to write front-ends, have you conducted any evals on how accessible those frontends come out?

2. How do you handle 3rd party libraries? Can the agent access library docs somehow? Considering that Elixir is less popular than more mainstream languages, and hence has less training data available, this seems like an important problem to solve.

sho|8 months ago

Watched the Tetris demo of this and it was very impressive. I was particularly surprised how well it seems to work with the brand-new scopes, despite the obvious lack of much prior art. How did you get around this, how much work was the prompt, and are you comfortable sharing it?

beepbooptheory|8 months ago

What is the benefit of this vs. just running your agent of choice in any ole container?

finder83|8 months ago

This looks amazing! I keep loving Phoenix more the more I use it.

I was curious what the pricing for this is? Is it normal fly pricing for an instance, and is there any AI cost or environment cost?

And can it do multiple projects on different domains?

Munksgaard|8 months ago

Just tried it out, but it's unclear what the different buttons at the bottom of the chat history does. The rightmost one (cloud with an upwards arrow) seems to do the same as the first?

causal|8 months ago

Do you have a package for calling LLM services we can use? This service is neat, but I don't need another LLM IDE built in Elixir but I COULD really use a way to call LLMs from Elixir.

arrowsmith|8 months ago

Thanks for everything you do Chris! Keep crushing it.

cosmic_cheese|8 months ago

How tightly coupled to Fly.io are generated apps?

Dowwie|8 months ago

What LLM(s) is the agent using? Are you fine-tuning the model? Is the agent/model development a proprietary effort?

jonator|8 months ago

I'm assuming you're using FLAME?

How do you protect the host Elixir app from the agent shell, runtime, etc

b0a04gl|8 months ago

how are they isolating ai agent state from app-level processes without breaking BEAM's supervision guarantees?

b0a04gl|8 months ago

the ai agent runs inside the same remote runtime as the app. does it share the BEAM vm or run as a port process?

ativzzz|8 months ago

This is very cool. I think the primary innovation here is twofold:

1. Remote agent - it's a containerized environment where the agent can run loose and do whatever - it doesn't need approval for user tasks because it's in an isolated environment (though it could still accidentally do destructive actions like edit git history). I think this alone is a separate service that needs to be productionized. When I run claude code in my terminal, automatically spin up the agent in an isolated environment (locally or remotely) and have it go wild. Easy to run things in parallel

2. Deep integration with fly. Everyone will be trying to embed AI deep into their product. Instead of having to talk to chatgpt and copy paste output, I should be able to directly interact with whatever product I'm using and interact with my data in the product using tools. In this case, it's deploying my web app

brainless|8 months ago

I have recently been working with Google Jules and it has a similar approach. It spins up VMs and goes through tasks given.

It does not handle any infrastructure, so no hosting. It allows me to set multiple small tasks, come back and check, confirm and move forward to see a new branch on GitHub. I open a PR, do my checks (locally if I need to) and merge.

risyachka|8 months ago

>> Remote agent - it's a containerized environment where the agent can run loose and do whatever

How is this innovation?

travisgriggs|8 months ago

I’m torn on “is this the future”.

I worked all day on a Phoenix app we’re developing for ag irrigation analysis. Of late, my “let’s see what $20/mo gets you” is Zed with its genetic offerings.

It actually writes very little Elixir code for me. Sometimes, I let it have a go, but mostly I end up rewriting that stuff. Elixir is fun, and using the programming model as intended is enlightening.

What I do direct it to write a lot is a huge amount of the HEEX stuff for me. With an eventual pass over and clean it up for me. I have not memorized all of the nuances of CSS and html. I do not want to. And writing it has got to be the worst syntactic experience in the history of programming. It’s like someone said people lisp was cool; rather than just gobs of nested parentheses, let’s double, nay triple, no quadruple down on that. We’ll bracket all our statements/elements with a PAIR of hard to type characters, and for funsies, we’ll make them out different words in there. And then when it came to years of how to express lists of things, it’s like someone said “gimme a little bit of ini, case insensitivity, etc”. And every year, we’ll publish new spec of new stuff that preserves the old while adding the new. I digress…

I view agentic coding as an indictment on how bad programming has gotten. I’m not saying there wouldn’t be value, but a huge amount of the appeal, is that web tech is like legalese filled with what are probably hidden bugs that are swallowed by browsers in a variety of u predictable ways. What a surprise that we’ve given up and decided the key tools do the probabilistic right thing. It’s not like we had a better chance of being any more correctly precise on our own anyway.

arrowsmith|8 months ago

Ah man I'm really happy to see this and excited to try it out.

As an Elixir enthusiast I've been worried that Elixir would fall behind because the LLMs don't write it as well as they write bigger languages like Python/JS. So I'm really glad to see such active effort to rectify this problem.

We're in safe hands.

acedTrex|8 months ago

LLMs not writing it well might be the biggest current selling point of elixir lol.

bad_haircut72|8 months ago

This is such a weird meme, Claude crushes elixir especially a fullstack app in liveview

bluehatbrit|8 months ago

This last few weeks I've been going hard on LLMs to put together a new prototype project. I've exclusively been using Claude Sonnet 3.7 within Zed (via github copilot) and it' fantastic.

From time to time it tries to do something a little old-school, but nothing significant really. It's very capable at spitting out entire new features, even in liveview.

Over all the experience has very productive, and at least on-par with my recent work on similar sized python and nextjs applications.

I think because I'm using mostly common and well understood packages it has a big leg up. I also made sure to initialise the phoenix project myself to start with so it didn't try to go off on some weird direction.

mrcwinn|8 months ago

Worried it might fall behind… further? I love LiveView, Phoenix, Elixir, OTP. But the ecosystem is a wasteland of abandoned packages.

If Phoenix.new helps solve that problem, I’m all for the effort. But otherwise, the sole focus of the community leaders of Elixir should be squarely and exactly focused on creating the incentives and dynamics to grow the base.

Compare, for example, Mastra in TypeScript or PydanticAI in Python. Elixir? Nothing.

Not here to bash. It’s more just a disappointment because otherwise I think nothing comes close.

throwawaymaths|8 months ago

in principle llms should do better on immutable languages since there is no risk a term will get modified by a distant function call.

victorbjorklund|8 months ago

I found them to be pretty solid for writing Elixir (not perfect but neither is it with JS) the last couple of months.

nxobject|8 months ago

Yeah – as someone who works in Common Lisp, I wish there was way to do complementary training for LLMs with existing corpora of codebases. Being able to read access documentation doesn't do much, unfortunately, to help with more general issues with correctness of output.

neya|8 months ago

I use o3, it's really good with Elixir. I prefer it to Claude, but Claude does a decent job as well.

If you want to take your website and business down, use ChatGPT-4o's code

pawelduda|8 months ago

Claude 3.5 produces very good Elixir/Phoenix code. Haven't tried 3.7 much but I assume it's only going to get better from here

te_chris|8 months ago

Claude and o3 are both excellent (if a bit erratic) elixir developers.

zorrolisto|8 months ago

Same, I watched a video from Theo where he says Next.js and Python will be the best languages because LLMs know them well, but if the model can infer, it shouldn’t be a problem.

itsautomatisch|8 months ago

Burnt through some credits pretty quickly. The first few minutes of using it felt like a glimpse of what it was supposed to be like, but otherwise it spent a lot of time not getting basic things right with the UI and before I knew it I was done. Roughly 90 minutes for $20 it's not a good value when you can ostensibly have the same experience on your computer and have control over every aspect. I still can't clone the latest revised version of the codebase it created to my local computer. Between that and Fly's non-existent documentation, no usage meter of some kind, and the lack of unpaid support (even though I am paying to use the service?) makes me want to avoid Fly, which is unfortunate because I think it does a lot of things right, especially the tunneling and dev experience outside of phoenix.new.

krainboltgreene|8 months ago

I've wasted a lot of time and energy on stuff that doesn't matter, so I can hardly judge anyone else on what they focus on, but man does it feel bad to have community leaders actively focus on building out tooling that is anti-worker. I think the only way I'd feel more conflicted is if Fly.io started building weapons systems for the military. I guess that wouldn't be shocking considering some of their lead's beliefs.

mrkurt|8 months ago

It's safe to say that if either Chris or I believed this to be anti worker, we wouldn't be working on it. He's spent the last 10+ years working on Phoenix specifically to improve the lives of the people doing the work.

My experience with software development is maybe different than yours. There's a massive amount of not-yet-built software that can improve peoples' lives, even in teeny tiny ways. Like 99.999% of what should exist, doesn't.

Building things faster with LLMs makes me more capable. It (so far) has not taken work away from the people I work with. It has made them more capable. We can all build better tools, and faster than we did 12 months ago.

Automation is disruptive to peoples' lives. I get that. It decreases the value of some hard earned skills. Developer automation, in my life at least, has also increased the value of other peoples' skills. I don't believe it's anti worker to build more tools for builders.

yunwal|8 months ago

The same logic that would lead one to believe that AI is anti-worker should also lead one to believe that software as a whole is anti-worker.

jonator|8 months ago

You can think of it as just automating the boring tedious stuff so us humans can focus on the harder problems like strategy, direction, design, GTM, etc.

The days are numbered where humans are sitting typing out code themselves.

It's akin to the numbered days of type writer secretaries of the 20th century.

wturner|8 months ago

Most tech isn't "Anti worker". What determines pro/anti worker are laws and government policies that reciprocate with the cultural norms we adopt. At the moment, money in U.S. politics is the most anti-worker phenomena I can think of. The ultra wealthy have a monopoly on the incentives that create policy and how our lives are ordered. The only power working people seem to have is the ability to impose consequences via rogue guerilla acts of protest and violence (Luigi Mangion) . Hopefully, AI is a Frankenstein monster the public learns to wield to facilitate more of these "consequences" and upend the monopoly the super wealthy have on policy incentives and change the way politics is funded for good. It's a new world and a Hawaiian or New Zealand doomsday bunker isn't going make a difference.

leafmeal|8 months ago

Do you believe making things easier and more accessible is bad for workers? I don't think it inherently is or isn't, it just depends on who benefits from the increased efficiency. I think that's more of a problem with your economic system, or wealth distribution.

Overall I think we would all be happier if efficient machines take away the drudgery of our daily work and allow us to focus on things that really matter to us. . . as long as our basic needs are met.

losvedir|8 months ago

This is very neat, and right up my alley as both someone really into Elixir and who thinks agentic AI is the future.

I have a question about how you manage context, and what model you use. Gemini seems the best at working with give context windows right now, but even that has its limitations. Thinking about working with Claude Code, a fair bit of my strategizing is in breaking down work and managing project state to keep context size manageable.

I'm watching the linked video and it's amazing seeing it in action, but I'm imagining continuing to work on a project and wondering if it will start losing its way so to speak. Can you have it summarize stuff, and can you start a session clean with those summaries, and have it "forget" files it won't need to use for this next feature, etc?

rustc|8 months ago

"Sign in with fly.io" takes me to a page asking me to pay $20 but the plan details are vague - what exactly is included in "$20/mo of Built-In AI Assistance Builds, refactors, and debugs right in your IDE"?

tptacek|8 months ago

This is a situation where we've been pushing on Chris to get this out into the world quickly, and there's a lot of packaging stuff like this that isn't fully put together yet. Thanks for calling it out! We'll get to it over the next week.

gavmor|8 months ago

Phoenix.new looks powerful, and I'll definitely play with it.

I've been daydreaming of an agentic framework that maximally exploits BEAM. This isn't that, but maybe jido[0] is what I'm looking for.

0. https://github.com/agentjido/jido

fridder|8 months ago

TIL; That is a very interesting library

CollinEMac|8 months ago

I'm a little surprised by the sentiment here that LLMs don't do well with Elixir. I've had a pretty good experience using AI tools on Phoenix/Elixir side projects.

arrowsmith|8 months ago

LLMs are definitely a lot better at Elixir than they used to be - the gap has closed somewhat. I still perceive a gap though, especially when trying to do more complicated things in Phoenix and LiveView (as opposed to just raw Elixir.)

Which LLMs do you use that you find are best with Elixir/Phoenix?

vaer-k|8 months ago

I've only used LLMs with Elixir, so I don't have any other experience for comparison, but I've found that although Claude frequently employs the wrong approaches in Elixir, I usually know when he'll have trouble and just ask him to read pertinent documentation first. So long as he's read the manual he seems to do just fine.

jsmo|8 months ago

Hmm, just signed up to check it out but no trial just "$20/mo of Built-In AI Assistance" without any mention of usage limits?

afro88|8 months ago

Same. Agents can be very expensive. Plus I have no idea how reliable or effective this actually is in practice. Would love to try it first.

zombiwoof|8 months ago

it's wild to me all this progress with AI, but at the same time, on my brand new mac, going through the readme to try out phoenix, it can't even get past the first step without an error (says it can't find postgres), yet the docs say I don't need postgres and it will default to sqllite if postgres and mysql can't be found.

hard to put confidence in AI vibe hacks when the basic stuff just doesn't work.

* (Mix) The database for Myapp.Repo couldn't be created: killed

Sytten|8 months ago

I am probably doing something wrong but I hate agents for coding. I like the autocomplete and the prompt to generate snippets but when it starts modifying code in many files so fast all at once, tries a bunch of stuff and never know when to stop it pisses me off more than anything else. Because most the time if it had stopped and let me do the 10% last part it would have been actual legit code.

artirdx|8 months ago

Mindblowing! This is 100x VB6. The generated UIs are beautiful and professional. I am still trying it out and building an app for tracking expenses but it is working very well. The conversational dialogue it has with the developer is just fantastic. I am amazed at how clear the user experience was in Chris' mind. I am not sure what LLM is being used but this is better experience than any LLM. Given this is first version, I look forward to what comes next!

Few issues:

1. The 150 message limit is understable but it suddenly pops up and you lose significant work. I was working on UI mockup and just as I had finished and was ready to go on implementation, this limit appeared and significant part of my work was lost. 2. After the first credit, the credit seems to exhaust pretty fast which makes it expensive, especially when you are trying it out. 3. Also I don't understand when you ask it to prototype different screens, why does it overwrites the same file. 4. It is not able to stop to seek user feedback but keeps trying different approach which kind of exhausts the credit. It would be nice if it describes its approach, so the human developer can provide their feedback. 5. It seems it is using OpenAI because it is often self-congratulatory to the point of being annoying sometimes.

psadri|8 months ago

I love the idea of Phoenix and server side rendering (I happen to work on SkyMass, a related project).

This is a tangential comment and should not detract from what Chris and team have created. I think closing the loop between agent and the running output is a great/critical step forward.

However, I find using AI to build transitional Apps with a UI is a bit like improving the way automobile steering wheels are made. In a world that soon won't need steering wheels at all.

If the AI is so good to write the code for an App, how much longer before you won't need those Apps in the first place? And then the question is, what will fill the role that Apps play today.

liampulles|8 months ago

I think it boils down to: if the AI screws up what I asked it to do, who do I have to hold accountable? If the answer is that there is no one I can hold accountable, because the AI agent I used removes any and all onus of responsibility in its terms of service, then I'm not going to use it for anything non-trivial.

colecut|8 months ago

I don't think we want to move to a world where everything we use is AI driven all the time.

A coded app is significantly more efficient to execute, and more predictable, than dealing with AI in most situations.

themgt|8 months ago

This looks really cool, but I gotta say I'm a bit uneasy with the apparent(?) closed-source + hosted + branding. "mix phx.new" is the way to generate a new Phoenix project, but "Phoenix.new" is closed source Fly.io product for building Phoenix projects?

Feels like we're getting into a weird situation if LLM providers are publishing open source agentic coding tools and OSS web app frameworks are publishing closed source/non-BYOK agentic coding tool. I realize this may not be an official "Phoenix" project but it seems analogous to DHH releasing a closed-source/hosted "Rails.new" service.

liampulles|8 months ago

This is very cool! I will say though, my spidey senses kick in when looking at stuff like this, and make me wonder about how much I'm going to get vendored in here. Could I use it develop a site off fly.io? If the answer is no, then I'd say this is cool and I think useful for people who need something quick and simple and out of the box, but not something I would ever use on a serious production project.

loloquwowndueo|8 months ago

The answer is yes. What would you say then?

There’s a “clone Git repo” thing in the left side bar, use that to clone the project locally, mix deps.get, mix phx.serve and you’re up. You can deploy this anywhere you want.

andy_ppp|8 months ago

It’s just producing Elixir/Phoenix code that is stored in GitHub and can be deployed anywhere.

moffers|8 months ago

The mental models of Elixir/OTP and AI Agents are very compatible. I’ve felt for a long time that it would be one of the best platforms for building AI agents.

zupa-hu|8 months ago

Would you elaborate why?

indigodaddy|8 months ago

So is Phoenix.new a Fly.io product, or just under the fly umbrella? Also, is pricing clearly laid out anywhere (including what the additional costs are for permanently deployed/hosted services that arise from Phoenix) ? Didn't dig too hard admittedly, but wasn't obvious where to find or look for pricing information on the front page on mobile

unvs|8 months ago

Any chance of open sourcing the model instructions for this? Do you feed it all the Phoenix/LiveView/Elixir docs, or have you written more specialised instructions?

I find Claude to have quite a bit of problems trying to navigate changesets + forms + streams in my codebase, just wondered if you had any tips of making it understand better :)

aytigra|8 months ago

A bit sad that the language and framework so enjoyable to write an read will be mostly hidden in a coding box.

And thinking about it made me realize that soon there will be a completely different programming language used solely by coding agents. ChatGPT gives an interesting take on this, "The fundamental shift is that such a language wouldn’t be written or read, but reasoned about and generated. It would be more like an interlingua between symbolic goals and executable semantics, verbose, unambiguous, self-modifying, auto-verifiable, evolving alongside the agents that use it").

troad|8 months ago

This makes me very uneasy. Not in what it is per se, but in what it shows about the direction of Phoenix.

I've been working with Phoenix a lot the last few months, and I like it a lot. But I do get the sense that the project suffers from wanting to perpetually chase the next new thing, even when that comes at the expense of the functional elegance and conceptual cohesiveness that I think is Phoenix' main strength.

LiveView is a great example. It's a very neat bit of tech, but it's shoe-horned surprisingly awkwardly into Phoenix. There's now a live view and non-live view way to do almost everything in Phoenix, and each has their own different foibles and edge cases. A lot of code needs to work with both (e.g. auth needs to happen at both levels, basically), meaning a surprising amount of code needs to have two, nearly identical variants: one with traditional Plug idioms, and then another using LiveView equivalents. Quick little view helpers end up with either convoluted 'what mode am I in?' branching, or (more likely) in view-mode-dependent wrappers around view-mode-independent abstractions. This touches even the simplest helpers (what is the current path?) and becomes more cumbersome from there. (And given the lack of static analysis for views, it can be non-trivial to even find out what is and isn't actually working where.)

Not every website should be a live view (e.g. hiking directions, for example), but that is clearly the direction of travel in Phoenix. Non-live views get the disparaging moniker 'dead views', and the old Phoenix.HTML helpers have been depreciated in favour of <.form />-style live components. The generators depend on those, plus Tailwind, Hero Icons and (soon) DaisyUI, all fetched live from various places on the Internet on build. This tight coupling to trendy dependencies will age poorly, and it makes for bumpy on-boarding (opinionated and tightly coupled isn't necessarily a smoother experience, just a more inflexible one).

So with all of that in mind, while I'm not shocked to see Phoenix jump on the vibe coding hype train, I guess I am disappointed.

The revelation that AI is now writing PRs for Phoenix itself is not confidence inspiring. I rely on frameworks like Phoenix because I don't want to have to think about the core abstractions around getting a website to my users; I want to focus on my business logic. But implicit in that choice is the assumption that someone is thinking about those things. If it's AI pushing out Phoenix updates now, my trust level and willingness to rely on this code drops dramatically. I also do not expect Phoenix' fraying conceptual cohesiveness to get any better if that's the way we're headed.

Phoenix is still an amazing piece of tech, but I wish I felt more at ease about its future trajectory.

ferfumarma|8 months ago

I love everything I read about Phoenix. It's definitely the framework I'm going to use the next time I need to scratch an itch.

Having a full stack that is easy to use as a learning sandbox is incredibly helpful in that regard, so this looks amazing.

krts-|8 months ago

This is incredible. It does seem quite expensive compared to Zed or Claude Code now it's on Pro. But neat enough I've burned through the $20 subscription credit despite being a bit of an AI sceptic. This seems to have a much better handle on UI design (unless I'm missing something with the other agents), but as a solo dev I'm becoming quite convinced. It's also got me to try out fly again.

I couldn't get Tidewave working but I must try again to see if Tidewave with Claude Code would offer this level of awesome.

ps. @fly - please let me buy more credit, I just get an error!

chrismccord|8 months ago

Thanks for the feedback! Send your fly email to chris@fly.io and I'll get things sorted out. We'll throw you some credits for the trouble :)

toolhouseAI|8 months ago

Hey @chrismccord, very confused but this is a collab between you and the FLY.IO project right? Like I can't eject the app from this and run it myself? This isn't an open source Phoenix project?

olafura|8 months ago

You can just use git to clone the code

ipnon|8 months ago

Chris is a hacker’s hacker.

nixpulvis|8 months ago

A hacker's hacker who charges for closed source AI tools which work in hosted environments only. Yea, right.

qudat|8 months ago

Technically this is really. Practically I don’t understand the point. Who is the target demographic? People that don’t have a local dev environment?

abrookewood|8 months ago

It's not really about the remote IDE. It's about an integrated environment where the agent can do everything it needs (install OS packages, inspect the code, view the app via a browser etc) in order to build what you want. It could end up being the place you 'start' an app, before exporting it and fleshing out the features locally.

nilirl|8 months ago

Beautiful demo! How do I build agents like this?

Does anyone know any great resources to learn how to design agents? Tool agnostic resources would be awesome.

chrismccord|8 months ago

Thanks! Everything is overly complicated in this space. It's probably far easier than you think. The open secret is it's just a loop that POST [provider]/chat/completions.

Elixir is particularly well suited here. In Elixir this is a genserver doing http posts and reacting to the token stream. The LiveView chat gets messages from the genserver agent regardless of where it is on the planet, and the agent also communicates with the phoenix channel websocket talking to the IDE machines with regular messages, again anywhere they are on the planet.

I talk about this quite a bit in my ElixirConfEU talk and distill things down: https://youtu.be/ojL_VHc4gLk?si=MzQmz-vofWxWDrmo&t=1040

mcdirty|8 months ago

This is great. I had to back out of a phoenix project and rewrite it in Django because I couldn't get good AI assistance. I'm pretty inexperienced with Elixir and Phoenix but understand the benefits enough to want to make projects in it. So this is really cool.

dontlaugh|8 months ago

I find that baffling. Why not just write the Elixir yourself?

causal|8 months ago

I had this experience too. Though most of my issues were with my model not necessarily with Elixir itself so much as understanding the Phoenix model, state, and CLI. Maybe even differences in versions? Wasn't always clear.

martypitt|8 months ago

This is really cool! And, that you did it in a few weeks is insane.

How did you get VS Code embedded in your app? I'm aware of projects like Monaco, and that vscode.dev exists - so it's clearly possible - but I didn't realize it was something others could build upon?

Again, kudos!

__0x01|8 months ago

What LLM does Phoenix.new use?

chrismccord|8 months ago

claude 4 sonnet as the main driver atm, and a mix of smaller models depending on the scenario

ethan_smith|8 months ago

Based on the blog post, Phoenix.new uses Claude 3 Opus as its underlying model, which explains its strong performance with Elixir/Phoenix codebases.

sergiotapia|8 months ago

What model is it using for all the agentic work?

What usage limits do we get with the $20 monthly price?

Thank you!

kuon|8 months ago

I really wish I could move to those nice new editors, but as a vim user I just feel paralyzed when I cannot use vim bindings. And all "emulations" I tried are just incomplete.

timeinput|8 months ago

I'm with you. I'm going to try Zed in the next couple days based on the response to my comment here. https://news.ycombinator.com/item?id=44322560 . I'm stuck with vim. My fingers nearly only work vim, but I managed to move to neovim, which worked. Maybe (something else) can work too.

chrismccord|8 months ago

as an avid vim user who moved to emacs evil-mode for a better vim than vim, and now who uses vscode with vscode-vim, it pains me to admit a web browser based editor is a better vim than vim. Somehow starts faster and is less kludgey and more scriptable. You can install extensions on phoenix.new, so vim is not a blocker for you. I drive vim emulation in it every day both on desktop app and within phoenix.new. Couldn't use it without it :)

loloquwowndueo|8 months ago

You can pull the repo, tweak it locally with Vim, push it back and ask the LLM to work on top of that. No need to use the built in IDE if you don’t like it.

poisonta|8 months ago

Phoenix needs an ActiveRecord-like database abstraction layer. Many Rails developers try Phoenix at some point because they may need better performance. They’re so accustomed to the Rails structure that they assume Rails has done everything right. However, Ecto and ActiveRecord are two very different beasts. When Rails developers try out Ecto, they often feel there’s too much boilerplate and believe the Rails design is much more intuitive. This, I think, is one reason Phoenix struggles to attract Rails developers. If it can’t please Rails users, it will rarely appeal to others.

lawn|8 months ago

The Ash framework is a data abstraction layer you light want to check out, although I'm not familiar with Rails/ActiveRecord to tell if it's closer to what they're after.

tobyhinloopen|8 months ago

My primary concern with Phoenix is how bad it performs in LLMs and I basically went back to Node/React/Rails for LLMs.

This is very exciting and I’ll check it out!

josefrichter|8 months ago

What you mean by performs bad in LLMs?

johnwheeler|8 months ago

Why wouldn't LLMs work as well with Elixir as python or JS? LLMs don't parse an AST.

lawn|8 months ago

Because of the amount of Python and JS in the wild is much more than the amount of Elixir code, so the LLMs have much more data to base their answers on.

rramon|8 months ago

Very cool. Does it use Phoenix 7 or 8 in the video?

chrismccord|8 months ago

1.8rc, which is going 1.8.0 momentarily

arrowsmith|8 months ago

1.7 or 1.8, not 7 or 8

sockboy|8 months ago

Integrating AI assistance directly into an Elixir IDE could boost productivity, especially for newcomers. Excited to see how remote SSH and local workflows develop!

artur_makly|8 months ago

For us SaaS Founders, GrowthHackers, Product folks, us non-devs.. What are some solid use-cases for it today?

mcdirty|8 months ago

Is the site down?

tough|8 months ago

this is the excuse i needed to revisit phoenix-elixir after a decade

ty fly team

asmodeuslucifer|8 months ago

Well of course I have to test it.

Disabled on news.ycombinator.com

citizenpaul|8 months ago

Heyy! Now we know why fly.io was shilling for AI a couple weeks ago.

"They are not making money off AI".was the most common response to my pointing out they were shilling AI. Feels good to be right.

lawn|8 months ago

Maybe you mean the "My AI Skeptic Friends Are All Nuts" blog post on fly.io?

Where they have this nugget about plagiarism:

> But if you’re a software developer playing this card? Cut me a little slack as I ask you to shove this concern up your ass. No profession has demonstrated more contempt for intellectual property.

So I guess if you have concerns about them using any code you upload using this tool you can shove it up your ass.

pier25|8 months ago

I'm surprised they are investing into this. I checked Phoenix recently because I was interested in LiveView and there isn't even an official AWS SDK for Elixir.

Honestly doubt the AI stuff is going to move the needle much if you can't even have a dependable S3 client.

chrismccord|8 months ago

Meanwhile I am a happy user of :ex_aws or :req_s3 which has done everything I need it to do. Object ops, iam policies, etc. A dependable S3 client has been there for years. The elixir core team doesn't need to maintain it. ReqS3 is one of my favorite things to use: https://hexdocs.pm/req_s3/readme.html

techpression|8 months ago

Considering the horror the official AWS CLI is this seems like a strange example. I’ve used both the non official libraries and they work fine. The one that is auto generated doesn’t feel very Elixir, but that’s to be expected.

olafura|8 months ago

What are you talking about, there has been a AWS client forever and I've never had a problem. It's not something you really need an official sdk for they are anyway often just reference because you might want different performance characteristics.

https://hex.pm/packages/ex_aws https://hex.pm/packages/ex_aws_s3

I've usually not seen more than 3 or so official SDK for most services and there are a lot more programming languages than that. For example Microsoft's Graph API doesn't have an official Ruby client, they have one that sort of works.

conradfr|8 months ago

But there's two actively non-official maintained libs.

4b11b4|8 months ago

Not sure what you're talking about..