SURREY STREET Partners
We Build What Others Advise On

COMMERCIAL
ARCHITECTURE
FOR B2B SAAS

Pricing changes, billing migrations, quote-to-cash rebuilds — and the monetization architecture AI products are going to need. We embed with product and finance teams to ship the systems revenue depends on. Not decks. Working software.

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INDEPENDENT THINKING,
OPERATIONAL INGENUITY,
UNYIELDING INTEGRITY.

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Our Approach

HANDS-ON
DELIVERY

We embed with your product and finance teams and build production systems — not decks. Our combined work spans quote-to-cash transformation at Atlassian ($3B ARR, 250K accounts, S-team priority), pricing and packaging rebuilds at Twilio (drove $600M in self-service revenue), Payment Intelligence at Braintree/PayPal (1.3% global auth lift, adopted by Uber and Airbnb), and open banking platforms at Wells Fargo (CFPB 1033, 1.5B+ API calls). AI monetization architecture is where the practice is heading now.

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A managing partner with an experienced advisor. 30+ combined years building production platforms in payments, open banking, capital markets, and AI — embedded with your team, not advising from the outside.

Vevina McAllister
Founder & Managing Partner
15+ years building platforms at the intersection of commerce, payments, and developer infrastructure. Twilio, PayPal/Braintree, Amazon, Atlassian, Zillow Group.
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Amy Hoffman
Advisor
15+ years building open banking, financial data, and trading infrastructure. Wells Fargo Open Banking, Dow Jones, Charles Schwab, E*TRADE, CBOE.
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Open Banking & Capital Markets
Platform Practice
CFPB 1033 compliance, financial data APIs, derivatives and futures trading platforms, market data infrastructure.
Payments, Commerce & AI
Product Practice
Authorization optimization, headless commerce, multi-party transactions, agentic workflows, and AI-native product strategy.
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Our Process

HOW WE WORK

Discover
We start by understanding your business, your stack, and the constraint that matters most — not by selling a methodology.
Architect
We design systems that work in production, not just on whiteboards. Every architecture decision maps to a business outcome.
Build
We write code, ship prototypes, and stand up infrastructure. Embedded with your team, working in your repos, on your timelines.
Validate
Every deliverable is tested against real users and real data. We don't hand off until it works — and you can prove it works.
What We Do

SIX PRACTICES

Monetization & Pricing
B2B pricing strategy, usage-based billing, packaging design, quote-to-cash, and revenue architecture for technical platforms.
Marketplaces & Partner Ecosystems
App and reseller marketplaces for B2B platforms — third-party app ecosystems, channel and partner pricing, revenue share and payout models, and entitlements across the ecosystem.
Payments & Commerce
Authorization models, headless commerce, multi-party transactions, and vault architecture.
Open Banking & Capital Markets
Financial data APIs, CFPB 1033, consumer-permissioned data, derivatives and market data infrastructure.
AI & Agentic Systems
Production agentic workflows, delegated authority and scoped permissions, AI monetization architecture.
Developer Platforms
Developer experience, SDKs, API design, and the PLG-to-enterprise commercial transition.
Recent Engagements
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LET'S BUILD
SOMETHING

We take on a small number of engagements at a time. If you're changing pricing, migrating billing, rebuilding onboarding, or just can't close your books cleanly — let's talk.

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