Expansive is an applied-AI firm for independent consultants, agencies and brands in market research, insights and analytics. We help you decide where AI changes how you work, then we build it, deploy it and make it stick.
Built and shipped:
19 years of consumer-insight work for brands including Google, Walmart, Microsoft and Gap Inc.
We help your firm decide where AI actually changes how you work, then we implement it. You end up with working practices, not a slide deck.
We build AI-native tools around your specific workflow and method, ship them to production, and put them in front of real users.
We put proven platforms, including PurchaseDecision, to work inside your existing marketing and analytics workflows.
Deliver the depth and speed of a larger shop with systems that do the legwork, without adding headcount.
Turn your methods into platforms you can run again and again, and bring new measurement to your clients faster.
Give your insights team evidence of what people actually do, in a form leadership can act on and defend.
Plenty of people have opinions about AI. These are systems designed and built end-to-end by Walter Carl, our founder, and they're running in production in front of real users.
Randomized forced-exposure experiments and observational AI-conversation studies. It measures what AI search answers, retail media and video ads actually change about real shoppers' purchase decisions.
AI-moderated qualitative research with recent buyers. An AI moderator interviews them, and a synthesis layer rolls each wave into findings on why people choose a brand, and why they don't.
A volunteer rebuild of the Insights Career Network's job platform, which connects people in the insights industry with the roles that need them.
A multiplayer card game rebuilt from four legacy repos into one TypeScript codebase that ships to web, iOS and Android.
A custom booking platform for a short-term rental in the Finger Lakes. It covers channel-manager integration, Stripe payments and an AI-assisted local guide.
A CRM replacement, document-extraction pipelines and customer-support automation: the unglamorous systems that give a small team the reach of a large one.
Expansive runs on agentic workflows and a company brain, so research, building and follow-through move faster than a traditional firm can staff them.
Walter is in the loop on every engagement for judgment, taste and ambition: what to build, what to skip, and when it's good enough to ship.
We stay independent and work alongside a network of strong independents and small firms. Each of us brings the others in when the work calls for it, so you get a specialist team without paying for a bench.
In 2007 Walter Carl, Ph.D. left a faculty position at Northeastern University to build what became Purchased, a consumer data and analytics firm. For nineteen years Walter built bespoke measurement systems for Google, Walmart, Microsoft, Gap Inc. and dozens of other global brands, always chasing the same question: why did this person buy, and why didn't that one?
Over the past year Walter has designed, built and shipped AI platforms and agentic workflows end-to-end, and the work above is the result. Expansive puts both halves together: deep knowledge of how insights work is bought and used, and the ability to build systems that do it.
Walter reads and answers every message.