LangChain raises $125M to build the platform for agent engineering

Congrats LC team!

I don't have much experience w/ "vanilla" LangChain or the LC Python tools, but I've been an avid user of Deployments and the LangGraph TypeScript SDK for like a year now (started using Deployments back when it was still called "LangGraph Platform"). I think I might be one of the oldest users of both...

To be honest, my first impressions were mixed. The Deployments product was very early/new and rough around the edges (bad monorepo support, for example). And the LangGraph TypeScript SDK felt... not super TypeScript-y. (I get the sense they ported over a bunch of abstractions from the Python package).

But the benefits outweighed the costs. In September 2024, Deployments + the LangGraph TypeScript SDK was one of the only ways that you could say FOR SURE that your agent was going to (a) work and (b) run smoothly in production.

(Also, their team worked hard as hell to ramp myself and my teammates up on agents. I was really won over by this and will be a LC stan forever as a result.)

Over the past year, I've seen both products evolve and mature significantly - to the point where all of those initial problems seem to have been addressed.

I still feel that the overhead associated with building and hosting your own agent from scratch is too much for most teams to take on, even at large companies. (In particular, first-class support for streaming is massive; this would be a huge PITA to build in-house.) I'm happy to let LangChain take care of all of this for me.

Overall, I've been very impressed at LC's ability to iterate and absorb feedback - especially when some of it is... not delivered in the kindest way. They're a very humble and hardworking team. Makes me happy to see them winning.

Hi HN! It’s been three years since we launched LangChain as an open source package. Since then, we’ve evolved into a broader platform for agent engineering (LangGraph, LangSmith). Our tools now power AI teams like Replit, Clay, Harvey, Vanta, Cloudflare, Rippling, Cisco, Workday, and many more. Our goal has always been to figure out what the agents of the future look like, and then build tools to help make them real.

Today we’re excited to announce new funding (at a $1.25B valuation) to allow us to continue building the platform for agent engineering, as well as new features and products.

And what I’m most excited about today is that we’re launching a number of new features and products: an insights agent in LangSmith, 1.0 releases of LangChain and LangGraph, and a no-code agent builder. We’ll talk a lot more about these throughout the week.

I’m excited to see how you like these new releases and get feedback. I'll hang out in the comments here for a while to answer any questions folks might have.