Case Study: Fey

Dec 11, 2023

Prior to Polygon, our journey included extensive trials with numerous API providers for our pricing feed, but each exhibited deficiencies. Polygon stood out, aligning with our high standards across the board—their data integrity, API stability, customer support, and documentation were all superior.

Dennis Brotzky, Co-Founder and Chief Technology Officer at Fey, is behind a product designed to simplify the overwhelming world of finance. People are busy, and Fey ensures that information is not just fast and accurate but also accessible and cleanly presented.

Over the past year, Fey’s team has achieved just that, building on top of the platform. Recently, Dennis upgraded his team’s subscription to our newest iteration of commercial offerings - Stocks Business. With their new subscription, the team at Fey has unlocked new capabilities for their application:

  • Real-time US Equities price data
  • Extended hours coverage
  • Public display privileges

“Fey’s mission is to simplify the financial world. Our goal is to provide insights that cut through the noise, helping customers make informed investment decisions,” Dennis explained. They’ve done a fantastic job at that, because their app looks as if Apple decided to design a Bloomberg Terminal.

Dennis’ role as CTO intersects deeply in both product development and design. This demands technical expertise and an understanding of how engineering choices impact the user experience and product design.

“Striking the right balance between simplicity and complexity is a continual challenge at Fey. Our design ethos is central to this balancing act—maintaining intuitive simplicity for our users while supporting advanced functionalities. The best feedback we receive is when people say Fey is beautiful and easy to understand without sacrificing data. That's when we know we've nailed it.”

One of my personal favorite features of Fey’s UX is the ability to quickly navigate using keyboard shortcuts. While unrelated to financial information and analysis, it feels empowering not to need a mouse while searching for new investment opportunities (and justifies my fancy light-up mechanical keyboard).

From Fey’s home view, I can follow a quick sequence of “/AAPL” > “F” > “Tab 2x” to instantly view AAPL’s Quarterly Balance Sheet information. From there, “Command E” will export that data for further analysis in Excel.

The abundance of data accessible through many investment analysis applications is frequently taken for granted. While this is now the status quo, it comes at a hefty price. Many notable firms spend hundreds of thousands of dollars a year to publicly display what seems to be widely accessible information. While many fintechs are actively ‘democratizing access’ to everything (including us), the landscape still makes it incredibly hard to up-start a disruptor in the sector. Dennis explains:

“In the early days of Fey, we faced a significant challenge: sourcing high-quality data without exorbitant costs. The market was dominated by large corporations holding exclusive control over data pipelines, paired with outdated technology that hindered access. But, data has become more equitable, and we're finding companies like are starting to make their mark. This shift proved crucial for Fey. Quality data is our lifeblood; without it, our mission to simplify the financial world would be unattainable.”

In some sense, Fey and Polygon’s missions are one and the same, just from different perspectives. Our mission has always been to simplify the financial world by equipping developers with the tools necessary to build the future of fintech. This means offering data products and packages that enable that mission. While historically, we have offered real-time price data products that did not incur per-user fee costs, the displays using these products were limited to living behind a login (entitlement) system. That is, until now. Unlike other data feed products marketed as having “Zero Licensing Fees,” our new Stocks Business plan offers clients the opportunity to enhance their products with public displays of highly accurate real-time data for all US Equities throughout the entire trading session (yes, even extended hours).

In addition to groundbreaking features, there are a few operational breakthroughs clients like Fey can take advantage of by switching to Stocks Business:

  • No need for exchange approvals.
  • No need to report monthly user counts.
  • No need to qualify users as pro/non-pro

Dennis noted that upgrading Fey to Stocks Business was a no-brainer.

“Working with Polygon has been transformative, enabling us to finally display pricing data publicly, eliminate monthly reporting requirements, and significantly reduce costs—a critical advantage in the current economic climate and a solid foundation for future integrations and use cases.”

Fey's advanced screener view

Fey is not new to the platform. In fact, they’ve been a customer for almost two years, using various APIs. The APIs include Aggregates for charting, Snapshots for bulk data retrieval, and News, Financials, and Ticker Details for displaying supplementary information. While we did not offer products with such advantageous display priveledges when Dennis first discovered our platform, he explained why our services stuck out when evaluating other offerings:

“Prior to Polygon, our journey included extensive trials with numerous API providers for our pricing feed, but each exhibited deficiencies. Our search for an accurate pricing feed led us to them after other providers fell short on precision, speed, and transparency. Polygon was the only service we found that delivered on this need and aligned with our high standards for user experience, data integrity, API stability, customer support, and documentation. They were all superior. Beyond the data quality, we needed to ensure the API was fast. Speed is a core value of Fey and having the fastest API was a must. I remember when we first tried Polygon that was the most impressive part. We've worked together for over a year and are still impressed with their service.”

At Polygon, we strive to create high-quality APIs that engineers enjoy working with. At our core, the platform is (incoming overused phrase) built by developers, for developers, so it's extremely encouraging to receive positive feedback from customers like Dennis.

Working with Fey over the past couple of years has been a pleasure, so I was ecstatic to hear that they officially launched the product a few months ago. If you haven’t already looked, I recommend checking them out.

We’re extremely thankful for Fey, as they have provided so much feedback, which has led to many product decisions and improvements.

We’re excited to continue rolling out features that help Fey and other fintechs go to market with the next generation of financial products.

If your team needs financial market data, please do not hesitate to contact We’d be happy to learn about your project and how we can help.

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