Very excited to announce that at 12:20am on the 4th of July, Aalo achieved criticality on our first full-scale reactor. We cut it close, but we pulled it off!! Working towards this goal with such an incredible group of humans has been the most fulfilling period of my life. This moment has been three years in the making. Last year, Executive Order 14301 called for at least three new reactors to go critical before July 4th, 2026. As of late last Friday night, that goal has been surpassed! When the EO was announced, we immediately sat down to figure out what the most ambitious scope would be, while still being potentially achievable by July 4th. Some of the team proposed doing simplified designs with smaller fuel loads, or building in existing facilities. One thing was clear: We wouldn't have time to integrate a full-scale sodium heat-removal loop to bring the reactor to its full 30 MWt. So here’s where we landed: ➡️ We purchased the entire commercial-scale fuel load. This is enough fuel to operate at 30 MWt / 10 MWe for 3 years before refueling. To my knowledge, it’s the largest fuel load that’s been taken critical in the DOE pilot program, by far. ➡️ We built a full-scale reactor vessel in our factory, and loaded in our commercial graphite layout. All the dimensions, vessel thickness, and manufacturing techniques are essentially the same as we will use for the imminent commercial version. There will be a few minor tweaks for sodium flow and full-power, but nothing major. ➡️ We built an entirely new reactor facility at the Idaho National Lab. Building a building is easy. Building a new reactor facility comes with a mountain of paperwork, policies, operation and training procedures, security, instrumentation and control, and more. Zero-power criticality might seem like a small step, but I can tell you, going through the exercise of building a reactor and taking it to criticality has been extremely valuable. The learnings on regulatory, ops, manufacturing, supply chain, QA, economics, engineering, and design will accelerate our path through to the final iteration at full-power. America is blessed to have a recent Cambrian explosion of startups in nuclear, all going after different markets, technologies, and strategies. I’m excited that sodium, gas, salt, and new PWRs are all getting pushed forward once again. The best outcome for humanity is to have all these advance in parallel, as quickly as possible, while maintaining safety. Thanks again to our amazing team, DOE, INL, BEA, and everyone else who helped us get to where we are today. This could not have happened anywhere else. Happy birthday, America!! 🇺🇸🇺🇸🇺🇸 There has never been a better time for nuclear energy. The Second Atomic Age has begun, and this one will be here to stay.

America turns 250 this week and Silicon Valley is still debating whether it's ok to work with the US military... Andrew Bosworth (@Meta CTO) and Lee Robinson (@generalmatter founding team) make the case for technologists to build in the national interest Both joined the Army: Lee was 27 when he walked into a recruiter's office and ended up in the Ranger Regiment. @boztank was 44, already exec at Meta, when he got a cold call from @ssankar They also serve America through the technologies they choose to build, from LLMs to uranium enrichment We cover: 8:25 - the unglamorous tech the country needs: chips, energy, manufacturing, infra 11:15 - how the US went from inventing uranium enrichment to producing 0.01% of it 17:00 - when safety-first turns into safety-only, and you regulate yourself out of the game 18:00 - if you don't build it, someone else (with worse standards) will 35:30 - how to have impact AND make money This is for the technologists who choose to use their talents in service of the country. Happy 4th!

If you have air conditioning running right now back east here's what's making your electricity. Burning dirty rocks from the ground are a big part of keeping cool in the heat. Shocking, but true. Don't tell anyone.

$6.7B in defense reindustrialization investment mapped businessdefense.gov/investme…

So the cat’s out of the bag…this past week, I decided to transition out of the federal government. I could not be more proud of the work we accomplished in nuclear, appreciative of the opportunities my leadership gave me at @ENERGY @NRCgov @DOGE @NASA,or thankful for the friendships that will endure for the rest of my life. My wife used to tell me you can do anything *for* a year. Now I know that you can do anything *in* a year, too. Between the Nuclear Lifecycle Innovation Campuses, pilot programs, NRC reform, super secret fuel cycle plays that may or may not be around the corner, and SR-1, I came to believe that we’ve cleared the biggest hurdles. Nuclear is all about execution risk now, and I couldn’t be happier. A lot of people are asking what’s next for me. Like my longtime hero, Cincinnatus, I plan to retire to my own little slice of heaven in the rolling Mediterranean hills (Russian Hill). I have a lot of dead plants to nurse back to health (replace with new ones) and a sink that needs fixing (two hours of morning deadlifts at Crunch on Polk). I have friends to see (if they live within walking distance of my apartment) and things to do (Stellaris “Nomads” update). Most importantly, I have a wife and dog who, after a year of sacrifice, deserve my love and attention (Stellaris “Nomads” update). I’ll have more to share about my next chapter over the coming weeks. Let’s keep building, friends.

Kazatomprom, the biggest uranium producer, won’t flood the market. To disincentivize mass production, the Kazakh government moved from a flat tax of 6% on the value of uranium produced to a tiered volume per mine: - Up to 500 tU per year: 4% - Above 4,000 tU: 18% More volume = much higher taxes. On top of that, there are price surcharges if uranium is expensive: - Above $70/lb: +0.5% - Above $110/lb: +2.5% These are just the highest and lowest tiers. One thing is clear: the Kazakh government wants value over volume and is disincentivizing mass production even in a high uranium price environment. This is a game changer.

.@CobiBGantz explains Palantir CTO @ssankar's "Hamburger Rule": "The hamburger rule is: bureaucrats and really anyone at a big company—they just want to do whatever it takes to go back and eat their lunch, eat their hamburger." "You need to make it easier for them to do what you want, so that they can get back to their hamburger." "If you're dealing with bureaucrats, the government, or large organizations—how do you make it easier for them to get back to eating their hamburger?" "This is actually a fundamental lesson in enterprise sales."

.@patrick_oshag Thanks for having me on, and for the extreme degree of presence and thoughtfulness throughout the conversation. To prevent the historical record from slowly drifting, I was “just” an intern in 2003 (team member 30-something) and went full time at SpaceX in 2004 (50-something). I once believed a company was big when it hit 50 people, but that was obviously wrong. The first 100 is the first 1% of a 10k person company. When a company has many chapters in its future, it’s always the early days. Scale invariance is a powerful thing.

Morgan Stanley on the Nuclear Renaissance: "We estimate the nuclear renaissance will be worth $2.2 trillion through 2050, up from $1.5 trillion projected last year, in the form of capital investment in new global nuclear capacity. This is based on an assumption that there will be 586.5GW of new nuclear capacity to be added globally, which is ~47% more than the current global nuclear capacity of 398GW. The growth will be led by China (~270GW) and the US (~150GW). China, the US, CEEMEA, and India will likely lead the rise in global nuclear capacity. With Asia emerging as the center of nuclear capacity growth, the region presents a number of opportunities for investors."

Let’s go!! Today, @ENERGY and @GovNuclear approved our Documented Safety Analysis (DSA) for the Mark-0 reactor. This is the FIRST-EVER approval for a new reactor. This marks the FINAL regulatory approval, confirming the reactor's as-built safety basis. Now, we enter the final phase of readiness, fueling and commissioning the reactor.

Great to sit down with my good friend Navin Girishankar on @CSIS’s latest episode of Betting on America to discuss how Pennsylvania can be the tip of the spear for our nation’s renewal. From AI and energy to defense and life sciences, we’re leading the way and showing what’s possible when we unleash American strength.

Interviewing Scott Nolan, Founder of General Matter, and James Danly, Deputy Secretary of the DOE next week on reshoring our capacity to enrich uranium, and powering the next century.

The US Export-Import Bank advanced plans for up to $4.2 billion in financing to support Japanese and South Korean nuclear operators’ purchase of enriched fuel from California-based General Matter bloomberg.com/news/articles/…