Anthropic announced the acquisition of Stainless, a developer tools startup founded by Alex Rattray, formerly of Stripe. The price of the operation exceeded USD 300 million, approximately double its USD 150 million valuation from its Series A in December 2024. What makes the move especially striking: Stainless was actively used by Anthropic's direct competitors, including OpenAI, Google, Meta, Cloudflare, Runway, Replicate, and Groq.

More than a technological acquisition, this move is a strategic play that changes the developer tooling landscape across the entire AI ecosystem.

What is Stainless and why was it so widely used?

Stainless built a very specific but very valuable tool: an automatic SDK generator. Its product took an API's specification and automatically created the code libraries that developers use to connect to that API, in multiple languages: Python, TypeScript, Go, Ruby, and others.

To understand the magnitude: every time a developer uses OpenAI's official Python library or Google's SDK for its models, part of that code was generated or managed with Stainless's tools. It's invisible but critical infrastructure for the AI ecosystem.

According to the report from TechCrunch, its customer base includes practically all the relevant players in the ecosystem: OpenAI, Google, Meta, Cloudflare, Runway, Replicate, Groq, and Cerebras.

What the acquisition includes and what changes for current customers

From the very day of the announcement, Anthropic began shutting down Stainless's hosted products:

• New sign-ups to the service: not available.

• Creation of new projects and SDK generation: not available.

• The SDKs already generated by existing customers: remain the property of those customers, with full rights to modify and extend them.

In other words, OpenAI and Google don't lose the SDKs they already have, but they will no longer be able to use Stainless's service to generate or update them. They will have to find alternatives or internalize that development.

Why it's striking that Anthropic's competitors used Stainless

In the tech industry, it's common for competitors to share third-party infrastructure: the same hosting, the same payment provider, the same development tools. But the scale of Stainless's adoption among the AI ecosystem's players has few comparisons.

The acquisition by Anthropic turns a neutral tool into an exclusive asset. It's the equivalent of one of the ecosystem's players buying the company that makes the keys everyone uses to open their cars: the others still have their keys, but they can no longer make copies.

Analyses from OpenTools highlight that the USD 300M+ valuation reflects the growing importance of the developer experience layer in the war between AI platforms.

If you're interested in seeing how the AI tooling ecosystem is evolving in the workplace, our article about Notion as a hub for AI agents analyzes how these platforms are becoming central infrastructure for work teams.

What it means for developers in LATAM

In the short term, the direct impact for most developers in Argentina and LATAM is low: existing SDKs work the same and current projects are not interrupted. But there are strategic implications worth understanding:

• The Claude ecosystem strengthens: Anthropic incorporates first-rate talent and technology to improve the experience of developers who work with its API and official SDKs.

• A signal of market consolidation: moves like this indicate that the big players are in a phase of acquiring to dominate layers of the infrastructure. Developers who understand this ecosystem are better positioned for the market to come.

• An opportunity for profiles that work with AI APIs: those who have skills to work with multiple APIs (OpenAI, Anthropic, Google) and build integrated applications will be increasingly valuable profiles in the regional tech market.

Recommended Coderhouse courses

If you want to be prepared to work in the consolidating AI ecosystem, these are the most relevant training programs:

• AI Engineering: for developers who want to specialize in building applications with language models, APIs, and AI SDKs professionally.

• AI Agents: learn to build autonomous agents with the APIs of the main models, including Anthropic's Claude.

• Full Stack Development Career: complete training for developers who want to incorporate AI into their work stack and increase their employability in the tech market.

Frequently asked questions

What is Stainless and what did it do?

Stainless was a dev tools startup that automated the generation of SDKs. It took an API's specification and automatically created the code libraries in multiple languages (Python, TypeScript, Go, Ruby) that developers use to connect to that API. It was used by OpenAI, Google, Meta, Cloudflare, and other key players in the AI ecosystem.

How much did Anthropic pay for Stainless?

The acquisition was for more than USD 300 million, approximately double the USD 150 million valuation Stainless had reached in its Series A round in late 2024.

Do OpenAI and Google lose their SDKs with this acquisition?

They don't lose the SDKs they already have. Anthropic confirmed that existing customers retain full ownership of the SDKs they already generated and have rights to modify them. What they won't be able to do is use Stainless's service to generate new SDKs or update them: that service was shut down for new operations from the day of the announcement.

Why did Anthropic acquire a startup its competitors used?

It's a strategic consolidation play. Anthropic incorporates first-rate talent and infrastructure to improve the developer experience of its ecosystem. At the same time, it eliminates a shared resource that all its rivals had: access to a neutral SDK-generation service that the whole industry used.

What impact does it have for developers in Argentina?

In the short term, the operational impact is minimal: existing SDKs work the same. In the longer term, the move signals an acceleration in the consolidation of the AI ecosystem, where platforms like Anthropic are investing heavily in developer experience. For Argentine developers who work with AI APIs, understanding this ecosystem is increasingly valuable in the job market.