Partnership Proposal · Confidential
Shimmy Books: escrow payments and a real basket
Replacing Stripe Connect with Trustap, and letting readers buy more than one book at a time.
Replacing Stripe Connect with Trustap, and letting readers buy more than one book at a time.
Shimmy Books already works. What is holding it back is the transaction layer: buyers have no protection when they send money to a stranger, sellers have to pass identity verification before they can list a single paperback, and nobody can buy more than one book at a time. This partnership replaces Stripe Connect with Trustap escrow and introduces multi-item carts, delivered as four workflows over two months on the Starter plan. After launch the partnership continues month to month, and you can raise the pace whenever the roadmap justifies it.
Marketplace Studio is a small team of senior operators who have designed, built, funded, and scaled two-sided platforms. We work with a handful of partners at a time so every build gets senior attention.
We think in supply and demand, liquidity, trust, and take rate, not generic web projects. Your build is shaped by people who have solved the chicken-and-egg problem before.
Product, design, and development are led by people with a decade in marketplaces, including founding and scaling well-known rental and services platforms.
We deliberately keep our active partner count low. You get continuity, context, and a team that treats your marketplace like its own.
Shimmy Books is positioned as the specialist alternative to a generalist resale app. That only holds if buying from a stranger here feels safer than buying from a stranger there, and if buying four books costs less than buying four books one at a time.
The value sits in two numbers. Basket size, because a reader browsing a seller's shelf wants several titles and single-item checkout forces them to pay postage four times, so they buy one or none. And supply, because every casual seller who abandons at the verification step is inventory your buyers never see. Escrow lifts conversion on the demand side; deferred verification lifts listings on the supply side.
Category focus is your defensible edge. A general resale app cannot justify book-specific search, condition language, or seller shelves, and it cannot make one parcel of four paperbacks feel like the obvious way to buy. Trustap gives you protection and dispute handling that would take a generalist a roadmap quarter to match, bought off the shelf rather than built and staffed.
We solve problems, we do not just ship features. Every workflow is grounded in your personas and validated before it goes live. Delivery is AI-first, which is how we move faster than a conventional agency without cutting quality.
Data and insight-driven decisions from research and user interviews. We empathize, define the problem, ideate, prototype, test, and iterate.
We use AI-accelerated development to turn validated designs into working software quickly. It is included in every plan, never surcharged.
Hybrid product-led development focused on your business requirements and the real problems your personas face, not features for their own sake.
A workflow is a complete build stream: we design it, build it AI-first, put it through automated QA, and ship it. Your plan is defined by how many workflows we run in parallel at any one time, from one on the starter plan up to five.
The more workflows we run at once, the faster your roadmap ships. It is the single lever that separates our plans, so you can dial delivery speed up or down as your budget and priorities change, month to month.
Pick how many workflows you want in flight at once.
Four workflows, run one at a time on the Starter plan across two months. They are sequenced so the payment rail is solid before the cart is built on top of it, and so your existing sellers are protected through cutover.
Replace the out-of-the-box Stripe Connect integration with Trustap. The buyer pays into escrow, the money is held until they confirm the book arrived as described, and Trustap runs any dispute rather than your support desk. This is the trust layer a stranger-to-stranger book sale needs and Stripe does not provide.
Today a seller must pass identity verification before they can list. That is a wall in front of your supply side. Trustap lets us move verification to the moment a seller withdraws their money, so someone clearing a shelf can list, sell, and only then verify.
Readers do not buy one book. A buyer can fill a basket from a single seller, see combined postage before committing, and check out once. One basket maps to one shipment, one escrow transaction, and one payout, which is what keeps the flow simple for both sides.
Seller re-onboarding sequenced by value, a staged cutover where in-flight Stripe orders finish on Stripe, and admin tooling that lets your team see and repair any transaction across both systems. This is the workflow that protects your existing supply through the switch.
Shimmy Books is a working marketplace, so this is a takeover, not a rebuild. We change the transaction layer and the surfaces that depend on it. Everything else stays exactly as it is.
You are on the Sharetribe Developer Platform with your own code repository, which is what makes this possible. A custom payment provider cannot be fitted to the no-code product. We work inside your codebase and you keep full ownership of it.
Card details are collected in Trustap's own payment interface, so no raw card data touches your infrastructure and you stay at the lightest PCI tier. Stripe stays live in payout-only mode through cutover, then is removed.
Quality is built in, not bolted on. Each workflow ships with automated end-to-end tests written in Playwright, so features keep working as your marketplace grows and new workflows land.
Playwright drives real user journeys (search, list, book, pay, review) the way your members will, catching breaks before they reach production.
Tests run as we build, so shipping a new workflow does not quietly break an old one. Your foundation stays solid month over month.
Automated QA is what lets us keep an AI-first pace without trading away reliability.
You manage the project through the Control Centre: your single source of truth for what is in flight, what is shipped, and what needs your input.
Track each workflow from design through QA to shipped, in real time, without chasing anyone for a status update.
Log issues, watch them move through triage, and see resolution against clear priorities, all in one view.
Review designs, approve work, and find your demo videos and release notes in the same place your team already works.
You always know when we meet, what we are shipping, and where things stand. Async updates and demos keep momentum between calls.
Two workshop meetings per week through a Design Thinking discovery sprint: empathize, define, ideate, prototype, test, iterate.
One call every two weeks, weekly written updates, async conversations as needed, and video demos as workflows ship.
Weekly calls in the two weeks before launch, plus bug tracking and release notes in the Control Centre.
Live testing and bug fixing, a friends-and-family closed beta, closed testing until we are confident, then public launch.
We stand behind what we ship. For 60 days after a workflow goes to production, we resolve any bugs in it at no cost. A bug is something that does not work as designed, distinct from a new enhancement, and everything is tracked transparently in the Control Centre.
Defects in delivered workflows: something built that does not behave as specified and agreed.
Raise it in the Control Centre, we triage by priority, resolve, and ship the fix with a note back to you.
Your ongoing subscription keeps us building, iterating, and supporting your marketplace as it grows.
You buy progress and access, not hours. No timesheets, no rate card. AI-accelerated delivery is included and never surcharged. Below is the package we recommend for Shimmy Books, what the same scope costs built the traditional way, and how the partnership continues once you are live.
After launch the partnership carries on month to month at the Starter rate. Nothing to renegotiate. When the roadmap justifies more pace, step up a plan and more workflows run in parallel. One month minimum, pause or cancel with two weeks notice.
Pricing shown is a draft for discussion and to be confirmed. Shown in USD. Canadian businesses are subject to local tax laws. Traditional development cost is an estimate for the same scope delivered conventionally, shown for comparison and not an option being quoted.
A senior PM is your conduit to the whole team, on Slack and email through the build and after launch.
A structured discovery with at least two of our team to uncover what will actually make your marketplace succeed.
Senior time on product strategy, SEO, and go-to-market, so growth is designed in from the start.
We do not disappear at launch. Your subscription keeps us iterating, supporting, and growing the platform with you.
Pick the number of parallel workflows that fits your pace and budget. We hold a start date on receipt of your first month.
We schedule kickoff and run our discovery sprint to lock the first workflows and success measures.
We stand up your Control Centre, environments, and shared design workspace.
Design begins immediately, and your first workflows move into build.
We keep a small number of partner slots open at a time and prioritise on mutual fit, marketplace potential, and commitment.
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