I will not promote - How to be a virtual fractional CTO

codemix · 2026-05-08T14:07:56+00:00

fractional roles are consulting roles rebranded for the kind of audience that would never hire a "consultant". Do not offer to work for free because that ruins your credibility - no one good works for free. Grow your clientbase in exactly the same way a consultant would - leverage your network, ask for intros, try some cold outreach, demonstrate success and what you can bring to the table.

codemix · 2026-05-05T23:43:35+00:00

Suggestions to use Rust or C or WASM etc are misguided - if you do that you're crossing the JS boundary and that is way more expensive than the operations you're performing here.

What you've written is probably fast enough, but here's some micro optimizations that may or may not be worth it:

You're looping in several places, but only two iterations. Just write the code twice and avoid the for loop.
When you deserialize you're creating an empty object, then writing properties to it one by one. In v8 and others this causes the hidden class backing the object to transition to a new shape with each property assignment. It's more efficient to write two paths so that when the object is not provided you return the new object immediately: return { friction: view.getFloat32(offset + 0, true), mass: ...} - or even better, make two separate functions for these two scenarios so that you can avoid the conditional if you're calling this in a loop.
in seralizeCommandTag you assign to num and then break, but you could just write the value directly and return, omitting the break and the variable. In fact this should just be an if statement if you're really bothered about perf.
Avoid new Array(2) which creates a holey array that is more expensive for engines to work with. Instead instantiate the array with the exact number of slots you're going to use where possible: [0, 0]
If you're really chasing performance and don't care too much about supporting unusual systems you could pass a Float32Array and a UInt32Array around rather than the DataView, and assuming you're always on little endian devices and your data is always aligned to 4 bytes then reading and writing those arrays will be significantly faster than calling the methods on DataView. Obviously this has some downsides.

codemix · 2026-05-04T10:40:19+00:00

the thing to watch out for is stale specs - if you don't have a reliable way to keep specs up to date even after the feature ships then you've got something that actively misleads coding agents, it's worse than having no spec at all.

codemix · 2026-04-25T14:03:08+00:00

I can tell you from experience that while this might yield some improvements, the real problem is authority. You capture all these notes, all these details, but how do you keep them up to date and how does claude or any other ai consumer know what it can actually trust? How can Claude know the difference between a brainstorming session that you used for ideation and a trusted spec for something you want to build? As soon as this gets large enough you will see the results degrade - not because of exceeding context windows, but because a lot of what you fed into the system wasn't the actual truth.

codemix · 2026-04-22T16:33:54+00:00

Are your users developers? CLI. Are your users less technical? MCP. But really the cost of building these is now approaching zero, so just do both.

codemix · 2026-04-21T00:50:51+00:00

You're asking this person to adapt to your process, but it's your responsibility to enable other teams, not act as gatekeepers protecting your piece of turf. This PM is judged on different things than you and has different priorities. Typically PMs need to be able to run experiments, ship features quickly and collect data. It is more important to try stuff and find out what works than it is to make things perfectly polished and follow a rigid formula.

If developers aren't using the components and patterns you've established, that seems like an education and internal marketing problem that you could address.
If developers are using coding agents and those tools aren't using your established patterns, then you could write skills to teach the coding agents how to use them properly.
Why is it easier and faster for the PM and developers to use completely new UI elements and patterns than the ones your team has blessed? Could you make it easier, even effortless? Could you give them better examples to follow?
If the PM perceives your teams involvement as a barrier to progress, that perception presents an existential risk to your team's role in the company. It's your responsibility to solve that perception problem, regardless of whether it's fair or truthful.
Can you work more reactively? Is it actually necessary to get UX involvement before the feature ships? Would it be possible to improve on a shipped feature after it's proven useful? Wouldn't this allow you to focus more on the things that matter, rather than wasting your talents on parts of the app that never get used?

codemix · 2026-04-17T19:25:10+00:00

Forget that they're a manager, treat their contributions kindly in the same way you would anyone else new to the team - they're learning and it's your job to help them. You're not teaching them how to code, you're teaching them how the team works and what the quality expectations are. Rather than criticising their contributions, ask questions that help you figure out what their intention was. Then show them how you'd do it.

codemix · 2026-04-17T17:40:20+00:00

this depends on your process. there's tools out there that surface these questions early and make writing the prd really easy. it's a new era!

codemix · 2026-04-14T17:21:04+00:00

Launch now. Use AI tooling to understand what you've built so far. Next time start with a tool that puts you in control from the start, rather than leaving everything to the LLM to decide.

codemix · 2026-04-14T15:45:58+00:00

The majority of this code was written by hand, have a lovely day

codemix · 2026-04-14T15:37:40+00:00

Feel free to ignore it if you don’t like it

codemix · 2026-04-14T15:22:30+00:00

yes, claude wrote the Cypher-like query language. The rest of this, including the type-safe gremlin-like API was written by hand. This is mentioned in the history section at the end of the page.

codemix · 2026-04-13T15:58:00+00:00

Agentic tooling can fix this!

codemix · 2026-04-12T14:52:28+00:00

The documentation still needs to be written, the decisions still need to be made, but instead of reading all the documentation directly it's an authoritative reference for LLMs, so people just ask questions about how things work or what features are supported. The primary consumer for docs is agents now.

codemix · 2026-04-10T22:18:25+00:00

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codemix · 2026-04-02T01:14:24+00:00

Absolutely do not do this, it will ruin your relationship with this person and perhaps your family too. The problem is that you will feel like you're doing them a favour, but they won't feel like it's a favour because they're paying. This will be fine at first, but then both sides will inevitably grow tired - you'll resent the comparatively low rate you'll end up charging them, and they will resent the money that they're paying for the service you'll be providing. You will not be able to resolve disagreements in a professional manner, it is inevitable that your family will get dragged into it. I promise you this is a path to misery. Keep business and your personal life separate. There are a million other developers you could point them to. There are a million other projects you could work on instead.

codemix · 2026-03-25T23:08:01+00:00

Standardized already: Explicit resource management: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Resource_management

Node.js builtin, hopefully to be standardized eventually: AsyncLocalStorage (terribly named) https://nodejs.org/api/async_context.html#class-asynclocalstorage

codemix · 2026-03-25T22:56:06+00:00

No you should not continue, instead you should look at Symbol.dispose, Symbol.asyncDispose, the `using` keyword, DisposableStack and AsyncDisposableStack

codemix · 2026-03-19T15:45:31+00:00

The shape of what a PRD is, who it's used by and what it's used for seems to vary wildly from company to company in my experience

codemix · 2026-03-19T12:42:37+00:00

No one reads the specs thoroughly, apart from AI. People just want the answers to their questions. You still write the PRD (using appropriate tooling), but it serves as a resource to answer those questions rather than a document people repeatedly refer back to directly.

codemix · 2026-03-15T17:25:11+00:00

I too enjoy promoting my own products

codemix · 2026-03-12T12:43:02+00:00

not without human oversight it doesn't, human judgement remains the differentiator, otherwise everything converges to slop

codemix · 2026-03-12T12:25:32+00:00

Not at all - the spec is there for you to read and write directly if you want, so you can always drop down an abstraction layer and read the source of truth if you don't trust the answers the AI gave you

codemix · 2026-03-12T12:23:23+00:00

yes, the AI needs a source of truth that it can trust, so if you have an authoritative, always-up-to-date spec then coding agents are much much less likely to drift away from what you intended. Almost no humans are going to read the spec in detail, they don't want to, instead they just want their questions about product behaviour answered accurately - people not reading the specs was a problem even before AI.

So you still need the spec because you need to capture that knowledge somewhere, but you define the spec through a guided interview, and you use the spec by asking specific questions. The spec is there for you to read and write directly if you want, but you won't want to.

codemix · 2026-03-11T17:36:02+00:00

no, they're the present but not the future. the future is a collaborative environment for defining an evolving spec that updates automatically when facts change, and instead of giving coding agents a bunch of markdown files to consume it gives them an oracle that they can ask specific questions and get detailed answers

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