DANIEL J. PENLEY, CFATRADING LEADERSHIP / HANDS-ON ENGINEERING

I understand thetrading desk.I build the technologybehind it.

For more than two decades I've built trading strategies, led teams, and developed systems inside private trading firms. Today I apply that experience to software for investment businesses, from broker integrations and market data to research tools and automation.

See what I build
TRADING EXPERIENCE+SOFTWARE ENGINEERING+BUSINESS JUDGMENT

01 / WORK

The interesting problems
are rarely neatly packaged.

My work ranges from building investment technology and automated trading systems to integrating the infrastructure around them. Here are a few examples from recent projects and previous roles.

01INVESTMENT TECHNOLOGY / INTEGRATION

Building technology from the ground up at an investment firm.

In an ongoing engagement with an investment firm, I've been building out its internal technology, including Python services, Supabase-backed applications, market-data pipelines, and tools for research and daily operations, with Vercel supporting deployment.

The work also includes a FIX adapter and IPSec connectivity, SFTP file management, systemd-based operational automation, and consolidated portfolio and risk views across multiple brokers. The goal is to make these systems work together reliably and serve the needs of the fund.

MULTI-BROKER PORTFOLIO & RISKFIX / IPSECSUPABASE / VERCEL
02TRADING SYSTEMS / EXECUTION

From trading research to live execution.

In recent work, I built an end-to-end trading system integrated with Interactive Brokers, bringing together backtesting, trading analytics, PostgreSQL-backed data, real-time intraday signals, and automated execution.

The system spans the full process, from testing ideas and interpreting live market information to generating orders and managing execution. I enjoy building both the research tools and the software that puts them to work.

INTERACTIVE BROKERSREAL-TIME SIGNALSPOSTGRESQL / AUTOMATED EXECUTION
FROM THE DESK / VIDEO

Automated market making in action.

00:26
A recording of my automated market-making software running alongside Interactive Brokers, with the trading interface and terminal output shown together.Open full-size video
03ALGORITHMIC TRADING / LEADERSHIP

Building trading systems with real financial accountability.

Previously, I developed and managed automated trading strategies across equities, equity options, and futures, including high-frequency market-making systems. The work spanned pricing, hedging, execution, risk, and production engineering, much of it in Python and C++.

I also led teams of traders, developers, and quants and was responsible for how those systems performed in live markets. That experience still shapes how I think about reliability, priorities, and engineering tradeoffs.

ALGORITHMIC STRATEGIESPYTHON & C++TRADING LEADERSHIP
THE WAY I SEE IT

The business problem comes first.
Then the architecture. Then the code.

NO EXTRA LAYERS JUST FOR THE SAKE OF IT.
02 / EXPERTISE

Trading judgment.
Engineering depth.

I've managed trading strategies and teams, and I've written the software behind them. I bring both perspectives to the same problem.

Trading technology

Execution workflows, broker connectivity, market data, legacy platforms, and operational tools. I know how these systems are used because I have worked on both sides of the desk.

TRADING PLATFORMS / BROKER APIS / OPERATIONS

Software & data

Python services, PostgreSQL, Supabase, Vercel, and DigitalOcean cloud infrastructure, along with the integrations that keep data moving accurately. I choose tools for how well they serve the business and how practical they are to maintain.

PYTHON / POSTGRESQL / SUPABASE / VERCEL / DIGITALOCEAN

AI-assisted engineering

I use AI coding tools, including Claude Code, extensively in my development workflow. They help me move faster on research tools, trading analytics, and complex software while keeping architecture and correctness in focus.

CLAUDE CODE / AI-ASSISTED DEVELOPMENT / AUTOMATION
03 / ABOUT

The experience
behind the work.

Daniel J. Penley, CFA
Portrait of Daniel J. Penley

I've spent more than two decades in algorithmic trading across equities, options, and futures. I've been a trader, portfolio manager, and senior leader, responsible for strategies, technology, and the people running them.

I've designed and operated automated trading systems in live markets, with responsibility for their performance, risk, and day-to-day reliability. I've also led teams of traders, developers, and quants while staying close to the engineering, particularly Python, C++, and Linux.

Today, through Atlas Trading II LLC, I work independently with investment teams and founders. I bring trading judgment, software architecture experience, and the ability to get into the code and build what the business needs.

More about me on LinkedIn
04 / CONTACTTECHNOLOGY, MARKETS & WHAT TO BUILD NEXT

Let's work
together.

I'm open to selective consulting work, technical collaborations, and new ventures, especially where markets, operations, and software meet. If you're tackling something interesting, I'd enjoy hearing about it.

dan.penley@atlastrading.com
LinkedIn Or just send me an email.

Based in Bloomington, Indiana. Working primarily remotely, with occasional travel.