fintech-engineer

Q: How do I install fintech-engineer?

Run npx skills add https://github.com/404kidwiz/claude-supercode-skills --skill fintech-engineer in your project. The skills CLI detects the agents you use and copies the skill into the right folder. For Claude Code you can also place the skill folder at ~/.claude/skills/fintech-engineer/ (personal) or .claude/skills/fintech-engineer/ (project).

by 404kidwizSecurity

Expert in financial technology systems, double-entry ledger design, high-precision math, and regulatory compliance. Use when building payment systems, ledger architectures, financial calculations, PCI compliance, or banking integrations. Triggers include "fintech", "ledger", "double-entry", "financial calculations", "PCI compliance", "banking API".

Installs: 148
Last 24h: —
Trending rank: —
Security: Not audited

Install

Works with every agent the skills CLI supports.

npx skills add https://github.com/404kidwiz/claude-supercode-skills --skill fintech-engineer

01
Install
Run the command in your project. The CLI asks which agents to install for.
02
Describe the task
Ask your agent for something this skill covers. It loads fintech-engineer automatically when relevant.
03
Review the result
The agent follows the SKILL.md steps, scripts and references bundled with the skill.

SKILL.md

The instructions your agent reads when the skill is triggered.

Fintech Engineer

Purpose

Provides expert guidance on building financial technology systems with proper accounting principles, regulatory compliance, and high-precision calculations. Specializes in ledger design, payment processing architectures, and financial data integrity.

When to Use

Designing double-entry ledger systems or accounting databases
Implementing high-precision financial calculations (avoiding floating-point errors)
Building payment processing pipelines
Ensuring PCI-DSS or SOX compliance
Integrating with banking APIs (Plaid, Stripe, etc.)
Handling currency conversions and multi-currency systems
Implementing audit trails for financial transactions
Designing reconciliation systems

Quick Start

Invoke this skill when:

Building ledger or accounting systems
Implementing financial calculations requiring precision
Designing payment processing architectures
Ensuring regulatory compliance (PCI, SOX, PSD2)
Integrating banking or payment APIs

Do NOT invoke when:

General database design without financial context → use /database-administrator
API integration without financial specifics → use /api-designer
Generic security hardening → use /security-engineer
ML-based fraud detection models → use /ml-engineer

Decision Framework

Financial Calculation Needed?
├── Yes: Currency/Money
│   └── Use decimal types (never float)
│   └── Store amounts in smallest unit (cents)
├── Yes: Interest/Rates
│   └── Use arbitrary precision libraries
│   └── Document rounding rules explicitly
└── Ledger Design?
    ├── Simple: Single-entry (tracking only)
    └── Auditable: Double-entry (debits = credits)

Core Workflows

1. Double-Entry Ledger Implementation

Define chart of accounts (assets, liabilities, equity, revenue, expenses)
Create journal entry table with debit/credit columns
Implement balance validation (sum of debits = sum of credits)
Add audit trail with immutable transaction logs
Build reconciliation queries

2. Payment Processing Pipeline

Validate payment request and idempotency key
Create pending transaction record
Call payment processor with retry logic
Handle webhook for async confirmation
Update ledger entries atomically
Generate receipt and audit log

3. Precision Calculation Setup

Choose appropriate numeric type (DECIMAL, NUMERIC, BigDecimal)
Define scale (decimal places) based on currency
Implement rounding rules per jurisdiction
Create calculation helper functions
Add validation for overflow/underflow

Best Practices

Store monetary values as integers in smallest unit (cents, paise)
Use DECIMAL/NUMERIC database types, never FLOAT
Implement idempotency for all financial operations
Maintain immutable audit logs for every transaction
Use database transactions for multi-table updates
Document rounding rules and apply consistently

Anti-Patterns

Anti-Pattern	Problem	Correct Approach
Using floats for money	Precision errors accumulate	Use decimal types or integer cents
Mutable transaction records	Audit trail destroyed	Append-only logs, soft deletes
Missing idempotency	Duplicate charges possible	Idempotency keys on all mutations
Single-entry for auditable systems	Cannot reconcile or audit	Double-entry with balanced journals
Hardcoded tax rates	Compliance failures	Configuration-driven, versioned rules

FAQ

What does the fintech-engineer skill do?

How do I install fintech-engineer?

Run npx skills add https://github.com/404kidwiz/claude-supercode-skills --skill fintech-engineer in your project. The skills CLI detects the agents you use and copies the skill into the right folder. For Claude Code you can also place the skill folder at ~/.claude/skills/fintech-engineer/ (personal) or .claude/skills/fintech-engineer/ (project).

Which AI agents can use fintech-engineer?

Any agent that supports the open Agent Skills format (a folder with a SKILL.md file), including Claude Code, Codex, Cursor, GitHub Copilot, Gemini CLI, Windsurf, Cline, OpenCode and more.

Is fintech-engineer safe to install?

No partner security audit is available yet. Skills can run commands and scripts, so read the SKILL.md and any bundled files before installing.

Who maintains fintech-engineer?

It is published by 404kidwiz in 404kidwiz/claude-supercode-skills. It has 148 recorded installs.