Surplus is an incubator for software startups, organized by Manifund and “Surplus” is the value created through positive-sum trades; what markets produce in abundance.
Apply here by June 24! We’re open to many proposals, but here are three categories of projects we’re particularly well-suited to incubate. If your idea is adjacent — apply anyway!
LLM-powered tools that help people think better, work together, and build common knowledge.
Examples include:
Many important concepts could be translated for a wider audience, with thoughtful design and an eye for virality.
Examples include:
Marketplaces or platforms, addressing common problems in EA, AI safety, and others working towards a beautiful future.
Examples include:
We’re seeking founders who are:
Why does Surplus encourage for-profit corps?
First, there are many standard reasons to use a for-profit corporation when trying to do good. For-profits operate with tight feedback loops. They can be more certain that they produce value (see: gains from trade, Paul Graham on wealth, “surplus”). They can tap into a much larger pool of available financing. They compensate founders and employees with high upside upon a successful exit, and thereby draw in better talent.
For-profit models are surprisingly flexible: Elicit, Now is an excellent time to start a for-profit, given vast torrents of funding available from Anthropic employees and OpenAI Foundation. These funds are distributed out of 501c3 entities — but 501c3s can pay for for-profit services, and invest in for-profit corps. There’s a $100B market waiting to be constructed; shovels waiting to be sold.
And ideologically, we think that equity is a beautiful mechanism for value alignment and credit allocation. Manifund has previously experimented with impact certificates to bring this concept to the charity world; now, we think that plain ol’ corporate equity will work fine, maybe with a light sprinkling of retroactive funding or prize rounds or advance market commitments to finance public goods.
Why start a startup, rather than join a lab or an AI safety org?
It is absolutely the case that Anthropic or METR are great places to work. But maybe:
Why should I join an incubator, when vibecoding is so easy?
Building great software takes more than coding. Product taste, visual design, distribution, sales and marketing are all things that 2026 LLMs still fail at. We’ve developed these supplementary skills needed to ship successful products, and would love to foster them in a new generation of founders.
Beyond advice & mentorship, Surplus also provides a cohort of folks working on similar problems, some of whom may be great cofounders. And finally, an incubator is a container for focus, a commitment device, a way to hold yourself accountable and get your idea out into the world.
Do you accept non-software startups?
Maybe? We have the most experience on startups with a major software component, but have also built things like Manifest and Mox. Apply if you wish!
Is Surplus open to students?
Yes! If accepted to Surplus, we do ask that students plan to take a leave of absence in the fall, or otherwise prepare so you can work on your startup without distractions.
Can Surplus provide visas for international founders?
Yes! We can support accepted founders on a J-1 visa, through Mox. See Mox’s J-1 Global Expert Fellowship.