Two Y Combinator startups, one engineering team in Ljubljana
We built and shipped the products behind two YC-backed US startups: an AI investing app and a women's community platform. Here's what the work involved.
Y Combinator writes a $500,000 cheque, spends three months with the founders, and puts them in front of the room at Demo Day. Thousands of teams apply for every batch. The ones that get in, and the ones that turn the batch into a real seed round afterwards, almost never arrive with a deck and a waitlist. They arrive with something that works, with users in it, and with a metric that moves week over week.
Building that product is the part we help with.
Two of the US companies we work with are YC-backed: Yunit Inc. (YC W22), now shipping as Benson, and RealRoots Inc. (YC S25), at therealroots.com. Both are San Francisco–style consumer products with regulated or operational complexity underneath. Both were built and shipped by small Indigo Labs team working from Slovenia.
Benson: an AI advisor that has to actually place the trade
Yunit came to us with an AI-driven investing product where the conversation is the interface. A user talks to the advisor, the advisor reads the real portfolio state, and the user approves — then a real order goes to a real brokerage.
Our team of three works across the engineering behind it: agentic AI development on OpenAI and ElevenLabs, a Node.js backend, iOS and Expo clients, payments and lifecycle email, and CI/CD on AWS. Two of us also act as fractional CTO, which in practice means we are in the architectural and business calls, not just the tickets. Product direction stays with Phillip and his team — we are the engineering half of that conversation.
The hard part was never the chat. It was making an AI agent operate the same tools the operators use, safely, with a human approving every transaction, in a product where being confidently wrong has consequences. Benson now runs on iOS and Android and sits at 4.8 on the App Store.
"They are incredibly timely with deliverables and have great proactive communication."
— Phillip Aubrey, CEO, Yunit Inc. (Benson, YC W22) · 5.0 verified review on Clutch
What he singled out as the differentiator was iteration speed and the originality of the solutions we brought back — which is the thing that actually matters when you have a weekly deliverable cadence and a runway.
Our contribution: AI agentic development · Backend · Frontend · CI/CD · AWS · Fractional CTO
Stack: Node.js, Swift, Expo, OpenAI, ElevenLabs, AWS
RealRoots: a product the founders can reshape without shipping a release
RealRoots turns a matching survey into a standing weekly friend group for women — onboarding, matching, then a six-week series of guided in-person experiences. It was one of the more talked-about companies coming out of the YC Summer 2025 batch.
We helped build the mobile app that carries the member journey, alongside the founders and their own engineers on the web platform. The design decision that mattered most, and one we argued for: content, copy and quiz flows are configured remotely from Firestore, so the team can rewrite the entire member experience in an afternoon without an app release or a store review. Around it, Firebase workers keep member, group and event data in sync between the web platform, the app and the operations side. On the mobile side we handle the builds and the store releases for both iOS and Android.
For an early-stage team, that combination — a team of two on our side, one year, one app on two stores, and iteration speed that isn't gated on us — is the difference between testing four ideas a month and testing one. RealRoots went on to raise its seed round from Y Combinator, Goodwater, Authentic Ventures and Lombardstreet Ventures, and was one of the companies investors singled out coming out of the S25 batch.
Our contribution: Mobile development · Backend · UX · DevOps
Stack: FlutterFlow, Node.js, Firebase, Airtable, Webflow
Why US founders end up in Slovenia
The pattern in both engagements is the same. The founders own the product and the market. We take a clearly bounded piece of the engineering and own it properly — including the decisions a CTO would make, not just the ones a contractor would take instructions on — and we work well next to whoever else is on the team. Teams of two or three, senior, overlapping with US hours, moving at the speed a batch and a runway demand.
Neither of these products is ours, and neither was built by us alone. That is rather the point: the founders kept control of their company, and got senior engineering capacity without spending months hiring for it.
If you are heading into a YC application, in a batch right now, or raising off the back of one, the fastest thing you can do is stop treating engineering as the bottleneck. We hold a 5.0 across ten verified reviews on Clutch, and Benson's founder left one of them.
Tell us what you're building → — we'll come back with a feasibility check and an estimate.