Jonah Cader

Partner at @lightspeedvp
Accelerating AI, infrastructure, and frontier tech
Prev @valorep

[Lightspeed @lightspeedvp]

The race to unlock fusion power is heating up.

@Helion_Energy is a fusion power company with a mission of producing a clean, zero-carbon electricity source. Two years ago, they launched their 7th-generation prototype, Polaris, and are now building their first fusion power plant in Washington.

We believe their progress in fusion power is remarkable, and that’s why we participated in their recent $465M Series G. This latest round brings Helion’s total valuation to $1.5B, reaching $15.5B post-money.

We believe a clean, reliable energy source is on the horizon, and that Helion is positioned to help lead the charge.

CC: Lightspeed partners @ravi_lsvp and @ravirajjain

[Ravi Mhatre @ravi_lsvp]

Fusion power could be one of the most important technologies of our lifetime.

That’s why @lightspeedvp first backed @Helion_Energy last year, and now we’re participating in their $465M Series G.

What has always stood out to us about the team is their willingness and conviction to tackle one of the most difficult scientific and engineering challenges imaginable: recreating the process that powers the sun to generate abundant energy here on earth.

After Helion completed initial construction on its 7th-generation prototype, dubbed “Polaris,” in 2024, the technology became the first privately funded fusion energy machine to do bulk thermonuclear fusion with deuterium-tritium fuel.

They’re building the path from the first power plant to many, toward a future where energy is no longer a constraint, but a catalyst. Congratulations to @Dkirtley , Chris Pihl, George Votroubek, Anthony Pancotti, and the entire team. Looking forward to this next phase of development.

CC: @ravirajjain

[Raviraj Jain @ravirajjain]

Abundant, affordable energy is essential for the future of innovation.

@Helion_Energy stands out as a company focused not only on the science behind fusion, but on the manufacturing, supply chain, and execution required to scale fusion.

@Lightspeedvp first backed Helion in 2025, and we’re excited to reaffirm our commitment to the company today and participate in their Series G.

Congratulations to @Dkirtley, Chris Pihl, George Votroubek, Anthony Pancotti, Prag Jain and the entire Helion team!

CC: @ravi_lsvp, @jonahcader

[Jonah Cader @jonahcader]

@clairejyz Welcome to the team, Claire!

[Ricursive Intelligence @RicursiveAI]

Honored to be named to the inaugural @Forbes AI 50 Brink List.

With a brilliant team and the backing of incredible investors, we're reducing the chip design cycle from years to days. AI can design better chips. Better chips can train better AI.

Join us: https://t.co/vR4jfmpeAk.

Full list: https://t.co/bx1LA4aIpc

[Lightspeed @lightspeedvp]

What if AI could design the chips that power the next generation of AI?

That’s the vision behind @RicursiveAI, an AI-driven semiconductor design platform that uses reinforcement learning to compress the chip development process from years to weeks.

We led their $300M Series A in January, and Co-Founders @annadgoldie and @Azaliamirh went in-depth about Ricursive and the future of AI-driven chip design in this episode of The Investment Memo with Lightspeed partner @guruchahal.

0:00 Welcome, Anna Goldie and Azalia Mirhoseini!
3:10 How the Idea for AI Chip Design Started
4:58 How They Expanded From Software to Chip Design
5:27 Turning the Idea Into a Google Moonshot
7:20 When Google Leadership Realized the Potential
10:35 Why Physical Design Is the Hardest Part of Chip Design
13:51 The 3-Phase Vision for the Future of Chip Design
17:51 Market Opportunity & Industry Disruption
20:24 The “Designless” Future of Hardware
22:04 Speed, Innovation & AI-Driven Exploration
21:00 The Role of Engineers in an AI-Driven Future
24:22 The Founders’ Unique Partnership Story
25:44 How They Hire World-Class Talent
27:05 Choosing the Right Investors
30:42 Advice for AI Researchers & Founders
33:16 What’s Most Important in the Next 12 months?

[Anna Goldie @annadgoldie]

Great conversation with Lightspeed's @guruchahal. Guru even shared the internal investment memo he used to pitch Ricursive to his partners!

[Azalia Mirhoseini @Azaliamirh]

It was great to chat with @guruchahal about Ricursive, chip design bottlenecks and what's next for this industry!

[Azalia Mirhoseini @Azaliamirh]

TechCrunch wrote a nice story about our $335M raise at Ricursive, some background and some of our plans!

https://t.co/zQ8OBI1ube

[Jonah Cader @jonahcader]

AI for chip design and chip design for AI.

@annadgoldie @Azaliamirh and the @RicursiveAI team are pursuing an audacious vision to co-evolve AI models and the silicon that powers them.

We're thrilled to lead Ricursive's $300M Series A and partner with them on this journey to build a full-stack semiconductor design platform that redefines the industry. Read more on our blog: https://t.co/oO8aqJXyhv

Cc @ravi_lsvp @guruchahal @lightspeedvp

[Jonah Cader @jonahcader]

@annadgoldie, @Azaliamirh, and the @RicursiveAI team are pursuing an audacious vision to co-evolve AI models and the silicon that powers them.

We're thrilled to lead Ricursive's $300M Series A and partner with them on this journey to build a full-stack semiconductor design platform that refines the industry. Read more on our blog: https://t.co/oO8aqJXyhv

Cc @ravi_lsvp, @guruchahal, @lightspeedvp

[Lightspeed @lightspeedvp]

Semiconductor design has become one of the biggest bottlenecks to AI progress. @RicursiveAI is addressing this by tightly integrating AI models with the chips they run.

Co-Founders @annadgoldie and @azaliamirh are rethinking how AI and chips co-evolve, and today we’re proud to lead their $300M Series A as they build the foundation for AI-native semiconductor design.

Congratulations to the entire Ricursive team!

Cc: Lightspeed Partners @guruchahal, @ravi_lsvp, and @jonahcader

[Ricursive Intelligence @RicursiveAI]

We raised a $300M Series A to realize our vision of recursive self-improvement, starting with AI for end-to-end chip design!

We sat down with @CadeMetz from NYT: https://t.co/QEPsffiObn

[Anna Goldie @annadgoldie]

Thrilled to announce our $300M Series A at a $4B valuation!

Chips are the fuel for AI. At Ricursive Intelligence, we are using AI to design better chips faster, closing the recursive self-improving loop between AI and hardware.

[Azalia Mirhoseini @Azaliamirh]

Ricursive has raised Series A! @annadgoldie and I had the chance to discuss our vision and the latest fundraise with @CadeMetz at @nytimes.

https://t.co/OdyblsVJDl

We are so grateful to our investors for their support as we build toward our vision of recursive self-improvement via AI for Chip Design and Chip Design for AI.