Cairn - Debt Payoff Coach with Side-by-Side Payoff Plans and No Offers
Debt Payoff App for a US Personal Finance Company
Designed and built a clickable debt payoff coach for a US personal finance company: every card and loan in one list, avalanche, snowball and custom plans compared against paying only the minimums, a minimum-only versus plan view on every debt, and a read-only credit score with no card or loan offers anywhere.
Most of our work is under NDA. Per agreement, we can share the work but not the company details - all names and identifying information shown here have been changed.
Impact
Home, debts overview, debt detail, payoff planner and credit score. Each of the 12 debts with a detail page in the demo, from cards to the excluded mortgage, opens its own page.
Avalanche, snowball and custom plans run month by month against a minimums-only baseline. On the demo budget of $1,950 a month: debt-free May 2029 with $7,384 interest on avalanche, against March 2036 and $18,619 on minimums only.
Each debt shows months and total interest paying only the minimum against the plan. For the demo's main card: 5 yr 4 mo and $6,250 against 1 yr 2 mo and $1,368, plus $281.14 a month to clear it in 36 months.
11 debts in the plan across cards, an auto loan, federal and private student loans, a personal loan, a medical bill, buy now pay later and a family loan, plus an excluded mortgage, 2 paid-off debts, 8 connections through Plaid and MX and 24 monthly score pulls.
The Problem
Lindenfield's research panel found that people with four to eight debts knew roughly what they owed but not the APR on each, which to pay first or when they would be done. Each lender's app showed one debt and nudged them toward the minimum payment, free credit score apps showed a number with no plan and plenty of card and loan offers, and the people in the worst shape stopped opening any app before anyone pointed them to free nonprofit help.
Our Solution
Cairn is one calm place for the whole picture. Members connect their cards and loans through an account aggregator, add medical bills and family loans by hand, compare avalanche, snowball and custom plans with the interest and debt-free date for each, and follow the chosen plan month by month. A Get help card is always visible, with lender call scripts and a hand-off to a nonprofit credit counselor.
The Challenge: A Plan People Can Trust
Lindenfield is free to use and earns money only from an optional subscription. It sells no loans or balance transfer cards, takes no referral fees and never sells data, so every screen had to help the member without selling them anything, using data that is often incomplete.
Incomplete Data From Many Lenders
Aggregators do not always return the APR or minimum payment, especially for private student loans and store cards, and medical bills, buy now pay later and family loans do not connect at all. The plan has to run anyway and say clearly which numbers are missing or assumed.
Credit Data Without Credit Repair
The score is an educational VantageScore 3.0 from a bureau partner, read through a soft pull that does not affect it. Lenders often use FICO, so every score screen names its model and bureau, and Cairn never promises a higher score, keeping it outside the Credit Repair Organizations Act.
Fair Marketing in Every Flow
UDAAP rules out unfair, deceptive or abusive practices. Cairn shows no credit offers, any Plus prompt is plain and hidden from members flagged as struggling, and cancelling has to be as easy as signing up.
Hardship Without Shame
Missed payments, collectors and lost income are the moments people stop opening the app. Late items use neutral amber and plain words, celebrations and streaks switch off in distress mode, and help, including FDCPA validation rights for debts in collection, sits one tap away.
Our Approach: From Payoff Rules to a Clickable Coach
Spec and Rules Research
Mapped 10 user roles, 38 screens across the member app and the internal console, and the data model for members, consents, connections, debts, payments, payoff plans and projections, credit snapshots, milestones, help check-ins and counselor referrals. Wrote down the rules the design follows: FCRA, the Credit Repair Organizations Act, GLBA and the FTC Safeguards Rule, UDAAP, the CARD Act minimum payment disclosure, FDCPA, TCPA and CAN-SPAM, the shifting CFPB Section 1033 rule and WCAG 2.2 AA.
Clickable Demo on a Production UI Kit
Built 5 key screens of the member app on a production dashboard kit: Home with the debt-free date and the next payments, the debts overview with weighted APR, utilisation and interest this month, debt detail with the minimum-only comparison, the payoff planner, and the credit score with factors and history. The planner's numbers come from a month-by-month simulation that follows the spec's rules, and actions run on local state.
What a Production Build Adds
Account aggregation through Plaid, MX or Finicity, soft-pull credit data from TransUnion or Equifax with identity verification, push, email and SMS reminders, App Store, Google Play and Stripe billing for Cairn Plus, and a headless CMS for guides and hardship scripts. Plus the remaining member screens, the internal console with support access by member code, ethics review for experiments, data export and deletion, and an append-only audit log.
Why It Works: The Whole Picture, No Sales Pitch
Trade-Offs in Plain Sight
The planner shows each strategy's debt-free date, total interest, interest saved and first payoff side by side. Labels mark the plan that saves the most and the one with the quickest first win, but none is pre-selected as recommended, and a budget below the minimums leads to Get help instead of a plan.
Every Number Shows Its Source
Balances carry the lender, aggregator and update time, the score names VantageScore 3.0 and TransUnion, and the weighted APR notes the debt with an unknown rate left out. Amber flags mark stale data or a missing APR, so a member knows what to check.
The Cost of the Minimum, Per Debt
Each debt puts minimum payments only next to the member's plan in months and interest, and for cards adds the payment needed to clear it in 36 months, the same kind of figure the CARD Act puts on statements, with a note that the statement's own numbers may differ.
Help Is Never Behind a Menu
A Finding it hard to keep up? card sits in the sidebar on every screen, and the Help item stays there if the card is hidden. Both open lender call scripts, a nonprofit credit counselor that Cairn is not paid to refer to, student loan and medical bill guidance, collection rights and a short list of debt settlement red flags.
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Enterprise Software Engineering - Human + AI
Contact Us
© 2026 - Copyright. All Rights reserved Oceanlab
Location
Global Headquarters
21 Merchant Road, 3rd Floor, Singapore 058267
Main corporate office and leadership operations
North America Office
548 Market Street, PMB 12345, San Francisco, CA 94104
Client operations and business development
India Office
402 Shivalik Shilp II, SG Highway, Ahmedabad 380015
Engineering and delivery center
Enterprise Software Engineering - Human + AI
Contact Us
Locations
Global Headquarters
21 Merchant Road, 3rd Floor, Singapore 058267
Main corporate office and leadership operations
North America Office
548 Market Street, PMB 12345, San Francisco, CA 94104
Client operations and business development
India Office
402 Shivalik Shilp II, SG Highway, Ahmedabad 380015
Engineering and delivery center
© 2026 - Copyright. All Rights reserved Oceanlab