[ Industry case study — Custom Software ]
Custom web app turns hours of audit calculations into seconds
Brainhub built the IRS QI Periodic Review Safe Harbor Sample Calculator, replacing Hartford Consulting's manual Excel process with an automated web app.
Original project by Brainhub ↗Industry reference — not a NexSum Labs engagement.
- Client
- Hartford Consulting
- Industry
- Financial compliance consulting
- Services
- Web app development, Product design, Business analysis, Payments integration
- Year
- 2025
- Location
- United Kingdom

The client
Hartford Consulting is a UK firm with over 25 years of expertise helping banks, fintechs, payment providers and crypto businesses fight financial crime and meet compliance requirements. Its services span KYC checks, suspicious activity reporting, training, tax and anti-tax-evasion measures, and crime detection systems.
The challenge
Many of Hartford's clients are US Qualified Intermediaries that must audit their processes, documentation and reporting every three years. Consultants calculated the required account samples by hand in Excel, which took hours. Hartford wanted a secure, intuitive tool that would also give clients an affordable alternative to large financial firms.
The solution
01Purpose-built calculator
Brainhub built the IRS QI Periodic Review Safe Harbor Sample Calculator from scratch, implementing the IRS-approved Safe Harbor sampling method.
02Flexible data import and reporting
Users upload account lists from xlsx, csv or Google Sheets; the app sizes each category's sample, selects accounts with a random generator and produces a downloadable report with full methodology.
03Credits, accounts and admin
Clients buy credits to run calculations, keep a calculation history in their account, and admins manage users and payments.


The results
Data collection and calculations that used to take hours now take seconds. The product was delivered on time, within scope and on budget by a four-person team. Hartford can now offer clients a cost-effective alternative to the services of large financial corporations.
“The app works perfectly, and they came in on time, on budget, with no outstanding issues.”
Tools & stack
Original project by Brainhub ↗ — published by the delivering agency, included here as an industry reference.
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