All Case Studies
FinTech / Tax Compliance (USA)

USTaxPenaltySaver

B2C FinTech SaaS — IRS Penalty Calculator & Resolution Platform

Full product build — research, design, development, deployment

Key Results

31
Calculators
IRS penalty types covered
21
PDF Generators
Professional letter templates
7,368
i18n Keys
Full EN/ES translation
<£70/yr
Infra Cost
Auto-scaling Cloud Run
80-95%
Cost Savings
vs CPA consultation

The Problem

Every year, the IRS issues tens of millions of penalty notices. Taxpayers face a harsh set of options: pay without questioning, hire a CPA at $200-500+/hr (often costing more than the penalty), or attempt self-resolution using the dense IRS website. There was no affordable middle ground.

Option
Cost
Accessibility
Completeness
CPA / Tax Attorney
$200-500+/hr
Appointments required
High (if affordable)
IRS.gov
Free
Poor UX
Partial
Free calculators
Free
Limited
Very low
USTaxPenaltySaver
$39.99
Self-service, bilingual
Full

What We Built

A comprehensive FinTech platform replacing expensive CPA consultations with intelligent self-service tools.

31 Penalty Calculators

Every major IRS penalty type covered — Failure-to-File, Failure-to-Pay, Estimated Tax (Form 2210), Accuracy (IRC 6662), Trust Fund Recovery, FBAR, Information Returns, ERC penalties, and more. Each calculator uses Zod-validated inputs and produces CPA-accurate results.

21 PDF Letter Generators

Professional, IRS-ready documents: FTA Abatement Letters, Reasonable Cause Letters (11 IRM categories), Form 843 prep sheets, CDP/Form 12153 letters, Streamlined Filing packages, TFRP defense docs, Innocent Spouse analysis, and more. Each includes IRS service center lookup, deadline calculations, and phone scripts.

AI Notice Scanner

OCR-powered pipeline using Google Cloud Vision that accepts photos of IRS notices, extracts notice codes, penalty amounts, tax year, and deadlines via regex patterns, then routes users to the appropriate calculator with pre-filled values.

Relief Discovery Engine

Smart eligibility engine evaluating across 11 IRS relief programs — surfacing recommendations as "Likely to Qualify", "Worth Exploring", and "Payment Options". Considers penalty type, filing status, business ownership, international exposure, and hardship indicators.

Interactive Denial Flow Wizard

Guided step-by-step experience for users whose initial relief request was denied: FTA Denied → Reasonable Cause → Audit Reconsideration → Payment Options. Each step explains denial reasons and guides to the next available option.

Complete Bilingual Support (EN/ES)

49 translated pages, 7,368 translation keys per language, zero missing translations. PDF output generates both English (for IRS submission) and Spanish (for user reference). Full i18n with next-intl framework.

Technology Stack

Frontend
Next.js 14 (App Router)
Backend
Next.js API Routes + Cloud Run
Database
Firebase / Firestore
AI / OCR
Google Cloud Vision API
PDF Generation
jsPDF (server-side)
i18n
next-intl (EN/ES)
Hosting
Google Cloud Run (us-central1)
Auth
Firebase Authentication
Testing
Vitest

Quality & Compliance

Development Metrics

Development phases111
Penalty calculators31
PDF generators21
IRS notice types covered30+
Relief programs modeled11
Research guides produced14

Security & Compliance

SSN-safe: only last 4 digits accepted/stored
US data residency (GCP us-central1)
Zod schemas + HTML sanitisation on all endpoints
Firebase Auth with Bearer token enforcement
Rate limiting (1,000/min, 1M/month)
HSTS, X-Frame-Options, CSP headers
CCPA compliant (Know, Delete, Export, Opt-Out)
Automated npm audit + TruffleHog scanning

Services Delivered

IRS domain research (14 technical guides)
Product strategy & UX design
Full-stack development (111 phases)
Penalty calculation engine (31 calculators)
PDF generation system (21 templates)
AI/OCR notice scanning pipeline
Bilingual i18n implementation
Security hardening & CCPA compliance
Production deployment & monitoring

What the Client Got

A production SaaS platform matching CPA-level output for penalty calculations and abatement letters
80-95% cost reduction vs professional tax consultation ($39.99 vs $200-500+)
Full US market coverage with state-specific penalty data (50 states + DC)
Complete Spanish support removing the language barrier for millions of taxpayers
Step-by-step guided workflows with phone scripts and fill-in-the-blank templates
Solo-founder ready infrastructure (under £70/year, auto-scaling, no DevOps needed)

Have a Similar Challenge?

From complex domain research to production-ready SaaS — we build platforms that replace expensive professional services with intelligent self-service tools.

Start Your Project