Crosshatch

Tools for agents –

[Crosshatch @CrosshatchDev]

To infinity and beyond

[Harry Solovay @harrysolovay]

Step 1 in enabling infinite traits:

Traits are now indexed into a local SQLite database.

~100× faster listings, ~4× faster lookups.

Up next: embeddings-based dynamic trait activation.

@CrosshatchDev

[Crosshatch @CrosshatchDev]

Win gar dium levi ohhh sa

[Harry Solovay @harrysolovay]

Btw traits give you telekinesis

[Crosshatch @CrosshatchDev]

If you're in Miami, make sure to join us at the Effect meetup!

[Ariel @ariazou]

🚀 Excited to welcome 𝗛𝗮𝗿𝗿𝘆 𝗦𝗼𝗹𝗼𝘃𝗮𝘆 (@harrysolovay) to 𝗘𝗳𝗳𝗲𝗰𝘁 𝗠𝗶𝗮𝗺𝗶 #𝟯!

I first discovered Harry through his incredible hardcore TypeScript tutorials on YouTube. His depth of knowledge, creativity, and ability to push the boundaries of the type system immediately stood out.

🎥 https://t.co/HobiO0052c

Harry is now building @crosshatchdev, an Effect-native toolkit for x402 payments, enabling applications and AI agents to seamlessly pay for and monetize APIs through programmable micropayments. Alongside projects like Liminal, his work continues to push the boundaries of what’s possible with TypeScript and Effect.

It’s a real privilege to have him share his ideas with the Miami developer community!

📅 November 9, 2026

📍 The LAB Miami, Wynwood

🎟️ RSVP: https://t.co/ENoCvVDmUn

@EffectTS_
#EffectMiami #EffectTS #TypeScript #AI #FunctionalProgramming #Crosshatch

[Sam Simonds @SamSimonds8]

Before getting traits checked, Opus 5.5 built with native JS (.map, .filter().length, Math.max(...spread), .padEnd)

With Traits, it realized this is an Effect app and actually used Effect utilities. Still work to do, but the journey toward desloppification is underway 🤏

[Crosshatch @CrosshatchDev]

A format for global desloppification

[Harry Solovay @harrysolovay]

Decision-model-validated lessons your agent infers from your feedback.

[Crosshatch @CrosshatchDev]

Desloppification, underway

[Sam Simonds @SamSimonds8]

Possibilities with decision models like Jev feel endless.

We're using it to build an open-source developer tool, Traits, that desloppifies AI codegen. Crazy future incoming https://t.co/2n3Dsi3FTh

[Crosshatch @CrosshatchDev]

What do we want?

Global desloppification.

When do we want it?

Now.

[Harry Solovay @harrysolovay]

Global desloppification, part 2:

You can't teach every lesson upfront — and you don't have to.

Correct your agent once. It saves the underlying insight for all future codegen.

[Crosshatch @CrosshatchDev]

Changes the game. Trait by trait.

[Sam Simonds @SamSimonds8]

Decision models change the game

[Crosshatch @CrosshatchDev]

Tick tock

[Harry Solovay @harrysolovay]

Decision models could damage Anthropic's business.

You don't need Opus 5.5 when you can instantaneously run hundreds of natural language assertions on agent output...

... at a fraction of the cost.

This approach is being streamlined via Traits.

https://t.co/YfEizoXUPH

[Crosshatch @CrosshatchDev]

Indeed it does

[Sam Simonds @SamSimonds8]

The post-slop era starts here.

[Crosshatch @CrosshatchDev]

Global desloppification imminent

[Harry Solovay @harrysolovay]

You ask your agent to rename `parse` to `decode`, but it keeps the old file name and aliases the import:

`import { decode as parse } from "./parse.ts"`

No lint rule can determine that this is slop.

System one models can...

[Crosshatch @CrosshatchDev]

How to enable devs to create payment-capable agents?

Reducing cognitive load is key.

Type signatures go a long way.

[Harry Solovay @harrysolovay]

Paying special attention to type signature legibility as I refactor the @CrosshatchDev known token type.

Type signature legibility is crucial for coding agents.

And also, it just feels dam good.

[Crosshatch @CrosshatchDev]

We'll get there.

[Harry Solovay @harrysolovay]

@MatthewStibbard @CrosshatchDev Consumer x402 isn't real quite yet––it'll require simplifying crypto ramping / autonomous wallets / new approaches to permissioned spend / unifying assets across networks. Consumers shouldn't need to reason about the infra itself. Lots of groundwork ahead, but we'll get there.

[Crosshatch @CrosshatchDev]

A preview of the next version of Crosshatch.

[Harry Solovay @harrysolovay]

All of the API's noise is slowly falling away.

What's left behind: minimal, composable building blocks for stablecoin payments with x402.

@CrosshatchDev

[Crosshatch @CrosshatchDev]

Yield all of the things

[Harry Solovay @harrysolovay]

Requiring x402 payment over HTTP, made easy.

In the next version of Crosshatch, payment `Required`s implement `Symbol.iterator` such that they can be directly yielded as HTTP effects.

Build the required. Yield it. Done.

@CrosshatchDev

[Harry Solovay @harrysolovay]

Currently revamping the @CrosshatchDev x402 merchant endpoint DX.

Thoughts?

[Harry Solovay @harrysolovay]

The @CrosshatchDev docs now sport a built-in MCP server.

This was extremely easy to enable thanks to Vocs and the Vocs @alchemy_run resource (currently in Alchemy's main, soon to be published).

Alchemy's framework support is getting stronger by the minute.

[Crosshatch @CrosshatchDev]

The ABC of x402 is three schemas:

- Payment required (our invoice)
- Payment payload (our signed check)
- Facilitator endpoints (our atm)

[Harry Solovay @harrysolovay]

A brief overview of x402

Payments for the AI era.

[Crosshatch @CrosshatchDev]

We're currently migrating the Crosshatch docs and facilitator proxy to a new Cloudflare account.

Apologies in advance for any downtime!

We will get everything operational again as swiftly as possible!

[Crosshatch @CrosshatchDev]

Crosshatch ❤️ alchemicals

[Harry Solovay @harrysolovay]

Experimenting with @alchemy_run composition patterns.

When I want to share layers across workers/DOs, I create a "prelude" effect, which executes during the infra run, and returns a layer, which I then provide to the runtime run.

So, a "prelude" is an `Effect<Layer<RIn>>`.