The Englander brothers, Arnie and Chaz, offer a compelling glimpse into the intersection of cutting-edge AI technology and the gritty realities of startup life, sharing their journey from early struggles to groundbreaking innovation in financial services. At the heart of their story is Model ML, an AI-powered workspace designed to revolutionize how finance professionals handle data and reporting. Chaz describes it as “akin to kind of the Office suite. So our own version of Word, PowerPoint, and Excel...” but with a transformative twist: instead of isolated tools, Model ML connects directly to all the data a person at a firm would normally use—emails, files, CRM systems, public filings, and custom datasets—creating what he calls a “cognitive architecture,” essentially a digital brain mirroring human access to information.
This integration saves users countless hours. Rather than manually hunting down data to build reports or presentations, the AI workspace automatically pulls everything together. Chaz sums it up perfectly: “If you had an Excel spreadsheet that was already connected into those data sources, you’d probably spend less time going and gathering information and analyzing it.” The result is like having a super-smart assistant handling the tedious parts of the job, freeing professionals to focus on higher-level analysis. The impact is tangible—“In the last seven days, we’ve signed the same number of contracts as we signed in the whole of Q4,” Chaz shares, underscoring the rapid adoption and value their product delivers.
Their firsthand experience navigating the messy, time-consuming world of investing sparked the creation of Model ML. After selling two startups, the brothers found themselves overwhelmed by the manual effort required to evaluate opportunities. Chaz recalls, “When we would receive an opportunity via email... it would then enter into this like a genetic system that, to be honest, we were just building for fun and kind of produced like a one pager for us.” This side project, which automatically gathered public data like LinkedIn profiles and comparable companies, evolved into the sophisticated AI workspace now transforming major financial firms.
The evolution of Model ML also reflects the rapid maturation of AI in finance. Chaz paints a vivid picture of the old way analysts worked: painstakingly assembling earnings summaries from quarterly reports, a process that “could take days.” Now, their AI can generate a nearly complete, perfectly formatted report dropped directly into Google Drive, often with accuracy surpassing human efforts. “Last year was a year of testing... this year everyone kind of, the whole world went from testing to using,” Chaz notes, emphasizing how AI has shifted from experimental to essential, with senior executives at top investment firms prioritizing its adoption.
One of the most exciting technological leaps has been in vision models capable of reading and analyzing tables, charts, and files with unprecedented precision. Arnie recalls the moment they realized the potential: “We were sitting next to each other, we were going crazy… OCR... combined with vision... it really just changed the game.” This breakthrough enables firms to automate routine data tasks confidently, freeing human talent for creative and strategic work.
Behind these innovations lies a wealth of startup wisdom shaped by the Englanders’ rollercoaster journey. They stress the importance of perseverance and passion. “You’ve got to be very passionate about what you’re building. You’ve got to have that perseverance,” Arnie advises. Chaz adds, “The consistency that we’ve noticed of founders that we’ve invested in or not work with is like the ones that kind of do that and really persevere tend to win.” Their story is a testament to sticking with an idea through tough times, as Chaz reflects on their early days: “We believe this is something that should exist. And we believe from a tech perspective, we could make it work. And it ended up doing so. But yeah, it was tough.”
Their hands-on approach extended beyond product development. In the early days, they personally delivered thousands of orders and navigated payment system failures by “just tak[ing] payments over the phone, taking payments with cash, taking payments with PayPal,” Arnie recalls. This grit and adaptability, combined with a relentless focus on customer connection—“We were speaking to a customer for every single order,” Chaz says—helped them iterate quickly and build trust. A memorable test of that trust came when a $1,800 drone rental went missing, prompting Chaz to track it down door to door, turning a potential crisis into a defining story of grit and credibility.
Scaling brought its own challenges, especially maintaining close ties to customers. Arnie emphasizes, “You’ve got to speak and listen to customers... The quicker we can ship things, the quicker we can learn.” This customer-centric mindset remains central as they build AI products that often surprise clients with possibilities they hadn’t imagined, reinforcing the importance of “building for them first.”
Co-founder dynamics also play a crucial role. Being siblings, the Englanders highlight honesty and clear communication as essential. “You need to be exactly that [transparent]. There can’t be any miscommunication... one of the biggest reasons startups fail is founder fallout,” Arnie warns. They divide roles based on strengths and interests, with Chaz joking about their “Venn diagram” overlapping mostly on customers and product, underscoring the balance needed to work effectively together.
Their experience with Y Combinator (YC) further shaped their approach. Choosing to join YC not once but three times wasn’t about funding but about immersing themselves in a culture of relentless drive and support. Chaz reflects, “You cannot replicate that,” recalling how YC pushed them to move from monthly to weekly, even daily reporting. Being part of YC’s “first really big AI batch” in San Francisco was electric, with Arnie describing the buzz of “working seven days a week” alongside other passionate founders and Chaz noting “almost daily or hourly, there was like a scientific breakthrough.” This environment accelerated their growth in ways they found nearly impossible to match elsewhere.
The brothers also grapple with the perennial question of where founders should build their companies. They admire San Francisco’s unmatched vibe and work ethic, describing scenes of people multitasking gym workouts with Zoom calls about funding rounds—a level of hustle “that just doesn’t happen” in the UK or Europe. Yet, they acknowledge Europe’s strengths, especially London’s “amazing engineering talent” and less competitive hiring landscape. Their advice is clear: “If you decide to stay in Europe, try to move to one of the few cities where there are other really ambitious people,” and if possible, be in San Francisco or a tier-one city to surround yourself with like-minded builders.
Balancing a global footprint, their engineering team is based in London, while about 80% of their customers are in the US. Chaz explains how they juggle time between New York, London, San Francisco, and Hong Kong, noting that many major technology decisions in finance now happen out of San Francisco rather than New York or London—a factor that might have influenced their early choices had they known.
Ultimately, the Englander brothers’ story is one of blending real-world experience, technological innovation, and relentless perseverance. From building a digital brain that transforms financial workflows to navigating the highs and lows of startup life, their journey underscores the power of passion, adaptability, and community. As Chaz puts it, “Building the plane, going down the runway is the best way to describe things,” capturing the essence of startup hustle and the exciting frontier of AI-driven finance.