Financial Technology • Web & Mobile Apps • API Development

Fintech Developer | Custom App Development Services

Experienced fintech developer specializing in custom web and mobile applications for financial services — trading platforms, portfolio management tools, and risk analysis systems built by a CFA Charterholder with MCIT from Penn.

  • Portfolio Management Tools
  • Fintech Mobile Apps
  • Risk Analysis Systems
  • Custom Financial Calculators
  • Financial Data & APIs
1‑hour Zoom • CFA Charterholder • MCIT from Penn
Ryan O'Connell CFA FRM Fintech Software Developer - Trading Platforms Portfolio Tools Financial Technology
Ryan O'Connell, CFA, FRM
Fintech Software Developer

Professional Fintech Development Expertise

Combining financial industry knowledge with software engineering excellence to deliver production-ready financial applications. From portfolio management tools to risk analysis systems, every solution is built with both financial rigor and technical precision.

Portfolio Management Tools

Advanced portfolio optimization, asset allocation, and risk management applications using Modern Portfolio Theory and quantitative methods.

Building sophisticated portfolio management systems that combine financial theory with practical implementation for investment advisors and asset managers.

Key Services Include:

  • Modern Portfolio Theory (MPT) Optimization - Efficient frontier calculation, Sharpe ratio maximization, and risk-return optimization utilizing advanced portfolio optimization tools
  • Risk-Return Analysis Tools - Monte Carlo simulations, VaR calculations, and scenario analysis
  • Rebalancing Automation - Automated rebalancing logic, tax-loss harvesting, and drift monitoring
  • Performance Attribution Systems - Factor-based attribution, benchmark comparisons, and contribution analysis
  • Custom Reporting Dashboards - Client-facing reports, regulatory compliance, and performance visualization
Technologies: Python (NumPy, Pandas, SciPy), JavaScript, React, Chart.js, D3.js

Financial Data & APIs

RESTful API development, data aggregation, and real-time financial data systems with enterprise-grade security and reliability.

Creating robust API infrastructure for financial data delivery, third-party integrations, and real-time streaming applications.

Key Services Include:

  • RESTful API Development - Custom API design, versioning, documentation, and authentication
  • Financial Data Aggregation - Multi-source data consolidation, normalization, and quality validation
  • Real-Time Streaming Data - WebSocket connections, pub/sub architectures, and low-latency delivery
  • Third-Party API Integration - Tiingo, Alpha Vantage, and custom provider connections
  • Data Security & Encryption - OAuth 2.0, JWT tokens, rate limiting, and secure data transmission
Technologies: PHP, Node.js, Python, REST/GraphQL, Redis, PostgreSQL

Fintech Mobile Apps

Native iOS and Android applications for financial services with real-time data, secure authentication, and intuitive user experiences.

Developing mobile-first financial applications that provide seamless experiences across devices with offline capabilities and push notifications.

Key Services Include:

  • Native iOS & Android Development - Platform-specific optimizations for maximum performance
  • Cross-Platform Solutions (React Native) - Code reusability across iOS and Android platforms
  • Real-Time Push Notifications - Price alerts, trade confirmations, and market updates
  • Biometric Authentication - Face ID, Touch ID, and fingerprint security integration
  • Offline Data Synchronization - Local caching, background sync, and conflict resolution
Technologies: React Native, Swift (iOS), Kotlin (Android), Flutter, Firebase

Risk Analysis Systems

Advanced risk modeling, Value at Risk (VaR) calculations, and stress testing frameworks for financial institutions.

Building comprehensive risk management systems that combine quantitative methods with regulatory compliance requirements.

Key Services Include:

  • Value at Risk (VaR) Calculators - Historical, parametric, and Monte Carlo VaR methodologies
  • Monte Carlo Simulation Engines - Multi-factor simulations for portfolio risk assessment
  • Stress Testing Frameworks - Scenario analysis, sensitivity testing, and regulatory compliance
  • Risk Dashboard Development - Real-time risk monitoring and exposure visualization
  • Compliance Reporting Tools - Automated regulatory reporting and audit trail generation
Technologies: Python (SciPy, NumPy), R, JavaScript, D3.js, SQL

Custom Financial Calculators

Interactive calculators for options pricing, bond valuation, DCF models, and custom financial formulas.

Creating user-friendly calculation tools that implement complex financial formulas with accuracy and professional presentation. Demonstrated through professional calculator suite used by thousands of finance professionals.

Key Services Include:

  • Options Pricing Calculators - Black-Scholes model, Greeks calculation, and implied volatility
  • Bond Valuation Tools - Yield to maturity, duration, convexity, and pricing calculations
  • DCF Modeling Interfaces - Discounted cash flow models with terminal value and WACC calculations
  • Retirement Planning Calculators - Savings projections, withdrawal strategies, and tax planning
  • Custom Formula Implementation - Proprietary calculations, industry-specific metrics, and specialized models
Technologies: JavaScript, Python, NumPy, Chart.js, HTML5

Portfolio of Fintech Development Work

Explore live financial applications demonstrating expertise in portfolio optimization, real-time market data integration, financial analysis, and custom calculator development. Each tool serves thousands of users and showcases production-quality fintech development.

Portfolio Optimization Tool

Professional portfolio optimization using Modern Portfolio Theory (MPT). Calculate optimal asset allocation to maximize Sharpe ratio with real-time market data and Monte Carlo simulation.

  • Sharpe ratio maximization
  • Monte Carlo simulation
  • Efficient frontier visualization
  • Custom constraints & parameters
Technologies: Python (NumPy, Pandas, SciPy), JavaScript, React
View Live Tool

Real-Time Stock Dashboard

Comprehensive stock analysis with real-time price data, financial statements, and key metrics. Institutional-quality data for professional investment analysis and research.

  • Real-time price data feeds
  • Financial statements analysis
  • Technical indicators & charts
  • Company fundamentals & metrics
Technologies: PHP, JavaScript, Tiingo API, Chart.js
View Live Tool

Stock Comparison Tool

Compare stocks side-by-side with comprehensive financial metrics, performance analysis, valuation ratios, and interactive investment growth charts for informed investment decisions.

  • Side-by-side stock comparison
  • P/E, P/B, PEG ratio analysis
  • Performance & dividend metrics
  • Investment growth visualization
Technologies: JavaScript, D3.js, REST APIs
View Live Tool

Professional Financial Calculators

Comprehensive suite of professional-grade financial calculators including options pricing, bond valuation, DCF models, and derivatives analysis tools for financial professionals.

  • Black-Scholes options pricing
  • Bond valuation & yield analysis
  • DCF modeling interfaces
  • Greeks calculation & visualization
Technologies: JavaScript, Python, NumPy, Chart.js
View Live Tool

Investment Analysis Tools

Suite of investment analysis and planning tools including risk assessment calculators, return projections, financial planning utilities, and custom formula implementations.

  • Risk assessment calculators
  • Return projection models
  • Financial planning tools
  • Custom formulas & metrics
Technologies: JavaScript, PHP, Responsive Design
View Live Tool

Fintech Development Services Pricing

Flexible pricing options based on project duration and complexity. All tiers include professional-grade code, testing, and documentation.

Basic

$399/hour

Short-term projects

(up to 1 month)

  • Quick turnaround time
  • Speedy yet accurate solutions
  • Highly customized applications
  • Professional code quality
Get Started
10% Discount

Professional

$359/hour

Medium-term projects

(1-3 months)

  • Comprehensive application development
  • In-depth testing & validation
  • Customized automation solutions
  • Code documentation & handoff
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Schedule Your Fintech Development Consultation

Discuss your project requirements, timeline, and technical specifications

Flexible Scheduling

Book a time that works for your schedule

Confidential NDA Available

Professional confidentiality guaranteed

Expert Guidance

CFA & FRM professional consultation

Fintech Development Technology Stack

Comprehensive technical expertise across modern development frameworks, financial APIs, and professional development practices for building robust fintech applications.

Frontend Technologies

Modern, responsive user interfaces with interactive data visualization and real-time updates.

React.js Vue.js JavaScript (ES6+) HTML5/CSS3 Bootstrap Chart.js D3.js

Backend Technologies

Robust server-side architecture with quantitative computing and database management capabilities.

Python (NumPy, Pandas, SciPy) PHP Node.js RESTful APIs GraphQL SQL/MySQL PostgreSQL Redis

Mobile Development

Cross-platform and native mobile applications for iOS and Android with real-time capabilities.

React Native iOS (Swift) Android (Kotlin) Flutter Firebase

Financial Data APIs

Real-time and historical market data integration from institutional-quality financial data providers.

Tiingo Alpha Vantage Yahoo Finance Quandl Bloomberg

Development Tools & Practices

Professional development workflow with version control, testing, and continuous integration.

Git GitHub Agile/Scrum API Documentation Unit Testing CI/CD Pipelines Docker

Technical Qualifications & Experience

Proven expertise combining financial industry knowledge with advanced software engineering capabilities

Professional Experience

8+ Years Financial Industry

Corporate finance and fintech technology background

Master's in Computer Science

MCIT from University of Pennsylvania with focus on software systems

YouTube Educator

60,000+ subscribers learning financial technology and programming

Production Applications

Live financial tools serving thousands of users daily

Education & Certifications

Master of Computer and Information Technology

University of Pennsylvania

Master of Science in Finance

Texas A&M University

CFA Charterholder

CFA Institute

Certified FRM

Global Association of Risk Professionals

Technical Excellence Meets Financial Expertise

Combining CFA credentials, Certified FRM designation, and a Master's in Computer Science from the University of Pennsylvania to deliver fintech applications that are both financially sound and technically robust.

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