Voltron Data Update: Transitions


Wes McKinney


October 23, 2023


TL;DR I am transitioning out of my full-time CTO role at Voltron Data so that I can expand my portfolio of entrepreneurial and open source data projects. While no longer serving in a full-time operational role, I will remain engaged as a Senior Advisor and will continue driving forward work to enable fast and interoperable analytical data systems.

In this post I will offer some highlights from the last 8 years since the founding of Apache Arrow and Ibis in 2015, from the creation of the not-for-profit Ursa Labs to founding Ursa Computing and Voltron Data, eventually raising over $115M in venture capital and making massive investments in the emerging open source Composable Data Stack.

2015 to 2020: Cloudera, Two Sigma, Ursa Labs, and Ursa Computing

In my September 15-year retrospective blog post, echoing our joint “Composable Data Management System Manifesto” from VLDB 2023, I offered a retrospective on how working on pandas and getting involved in the Python community starting in the late 2008 snowballed into a cascade of projects and collaborations, culminating in the recent focus on growing the ecosystems around projects like Apache Arrow and Ibis, which came about in 2015 when I was still at Cloudera (see two blogposts from that era).

In early 2016, a precipitous decline in public and private enterprise software valuations meant significant belt-tightening and a delayed IPO at Cloudera, and I saw the writing on the wall that I would need to look elsewhere to fund Arrow development (which at the time was not much more than a Markdown specification and a chunk of code split off from Apache Drill).

As fate would have it, I received a timely lifeline from technology leaders David Palaitis and Matt Greenwood at Two Sigma, who were compelled by the prospect of open source standards to enable better modularity and composability in data systems. Two Sigma had already been incorporating these ideas in their systems since the late 2000s. They offered both to hire me and to pay for additional engineers to work with me on Arrow while also supporting architecture work on their internal data processing platform. Aided by this investment, we were able to get Arrow off the ground quickly while working on real-world applications while identifying new project extensions like Arrow Flight that would bring enormous value. Two Sigma also saw the potential of Ibis as an extensible and portable user interface and DSL layer for coordinating both SQL and non-SQL analytics systems in a natural way from Python. Motivated by this, Phillip Cloud and Jeff Reback from the pandas core team would join me at Two Sigma to help make a Python-based and Arrow- and Ibis-powered Python data processing stack a reality.

A year into my tenure at Two Sigma, the ideas of interoperability, composability, and modularity had begun to percolate more evidently in the open source zeitgeist. I tried to articulate my perspective on these ideas in August 2017 at my JupyterCon talk “Data Science without Borders” (probably my favorite talk that I’ve done). Right around this time, I had spotted some interesting new GitHub repos and eventually a press release from Anaconda, h20.ai, and OmniSci (now Heavy.AI) announcing the GPU Open Analytics Initiative aka “GOAI”. Little did I know this would be the catalyst for the most intense six years of my career as an open source entrepreneur.

I was excited by GOAI and the idea of a “GPU DataFrame”, but I did not find much linking it to Arrow other than mentioning Arrow as inspiration for the GPU DataFrame in a GitHub repository. So I decided to go digging. GOAI did not initially involve a significant engineering investment from NVIDIA, but I quickly learned that a team there led by Josh Patterson was behind the scenes corralling many startups to work on GOAI and to provide NVIDIA hardware for them to develop on. It wasn’t straightforward to get included in the GOAI group, but eventually I was able to get involved and start working to align the efforts to the complementary goals of the (decidedly CPU-oriented at the time) Arrow ecosystem. I learned later that the initially-exclusive nature of the group was more driven by the intense market rivalries amongst the major hardware vendors than anything else.

Not long after GOAI started, Josh and team at NVIDIA were able to secure a significant commitment of budget and headcount to be able to build a development team inside NVIDIA to put serious developer muscle behind the vision for open source GPU-accelerated analytics. A little over a year after GOAI was announced, this beefed-up and now proudly Arrow-based effort was announced to the world at GTC Europe as RAPIDS. Hearing NVIDIA CEO Jensen Huang talk about me and Arrow on stage in his GTC keynote brought tears to my eyes.

(author’s note: Arrow was created by consortium of people, not just me!)

NVIDIA’s investment in RAPIDS also came with the ability to make strategic grants to projects and companies working on complementary initiatives, but at the time (I was a full-time employee at Two Sigma) it wasn’t straightforward for me to receive a development grant from NVIDIA. I considered simply going to work at NVIDIA (which in hindsight would have been highly lucrative), but I wanted to maintain a close collaboration with Two Sigma and to leave the door open to other fruitful collaborations as the Arrow ecosystem flourished. I also perceived Arrow’s role in enabling the “Data Science without Borders” vision, and wanted to try to engage language communities beyond Python.

With these things in mind, in early 2018 I received a second lifeline — this time from J.J. Allaire and Hadley Wickham at RStudio (now known as Posit). J.J., Hadley, and I had gotten to know each other years before that, and Hadley and I had teamed up to create the Feather format based on Arrow to show the potential of making Python and R work better together. We all agreed that the “language wars” between Python and R were counterproductive, and Posit recognized that the future of data science is polyglot. Investing in technology like Arrow would reap huge benefits for the R ecosystem and beyond.

J.J. offered to fund 4 full-time engineers and provide the “back office” operations for a not-for-profit organization where we could take in development grants from Two Sigma, NVIDIA, and others companies. This became Ursa Labs, and under this not-for-profit structure we were able to grow the team to 7 engineers and take in additional funding from Bloomberg, G-Research, Intel, and others. Neal Richardson joined me to lead Ursa Labs in early 2019 and with Posit’s support we were able to spend a couple of years working on Apache Arrow with almost no administrative overhead.

By mid-2020, Neal and I began to see that the next stage of Arrow ecosystem growth would benefit from a larger capital investment than we could secure for a not-for-profit endeavor. I consulted Chris Ré at Stanford, and he soon introduced me to early-stage investors Lip-Bu Tan and Amarjit Gill, who had stellar reputations and were interested in software projects that would help unlock the capabilities of modern hardware. I also reconnected with Dave Munichiello and Erik Nordlander at GV (who had invested in DataPad in 2013) for advice. It didn’t take long for us to put together an investor syndicate, and thus Neal and I founded Ursa Computing. Posit and Two Sigma received founders’ shares in this new company to honor their support and commitment to the vision of Apache Arrow.

Starting Voltron Data: From Idea to 100+ Person Team

Shortly after the transition in late 2020 to Ursa Computing, as I was catching up with Josh Patterson at NVIDIA, I learned that he and some engineering leaders from the RAPIDS team were interested in exploring data startup ideas. Our investors were thrilled about the prospect of synthesizing the best ideas around hardware acceleration, data, and language interfaces to create a unified software company, which we gave the code name “Voltron Data”. It wasn’t hard to convince Josh to jump on board with the project and become CEO, with me as CTO. BlazingSQL, which had worked closely with the RAPIDS team, was also keen to join the founding team. To complete the dream team, we recruited Silicon Valley legend Darren Haas, who built the first prototype of Siri and went on to lead teams at Apple, GE Digital, and Amazon AWS. Darren also founded Change.org and is a charismatic team builder. With the help of a lot of legal work, we all joined forces to create Voltron Data.

Investors agreed with our technology vision, and before long we had raised an additional $110M led by Lip-Bu Tan from Walden, on top of the $5M that we had previously raised from GV and Walden for Ursa Computing. This war chest has enabled us to build an amazing technical team and make significant investments across the emerging composable data stack. From the initial 30 or so people in Voltron Data, we have grown to over 100, more than 20 of which are devoted to working on open source projects like Arrow, Ibis, Substrait, and Velox.

In addition to our open source work, we have invested in collaborations and partnerships that are aligned with growing the Apache Arrow ecosystem and supporting the development of the composable data stack. For example, this includes collaborations with Snowflake and Velox as well as being a multi-year Gold sponsor of the DuckDB Foundation. We also launched a commercial support product, VESA, to be a development partner with organizations replatforming on technologies like Apache Arrow and Ibis. We see these collaborations as going hand-in-hand with new open source initiatives like nanoarrow and ADBC which are facilitating the transition to a more composable Arrow-based future. I’m really proud of what the team has accomplished so far, and our commitment to code quality and elevating engineering standards across these projects.

All startups as they transition from early- to mid-stage must focus on specific areas of product development and revenue growth in order to achieve long-term viability. This is especially true in 2023 and beyond as capital markets have become much tighter than they were in 2021 and 2022. Companies that lack focus or work on too many things generally do not fare well.

Personally, I have always been energized by the early stages of projects: identifying a problem, working really hard to assemble a team and bootstrap initial solutions, and then getting the project to a point where I don’t have to be involved 100% of the time, so others have an opportunity to step up and become leaders. This happened with pandas (where I handed off project leadership to the core team in 2013) and has recently reached this transitional point with Arrow and Ibis, which are extremely healthy and with excellent leadership. Similarly, I have recently felt that I have made my most valuable contributions to Voltron Data in helping it get off the ground, raise money, sharpen the thesis around modular and composable data systems, and assemble a top-notch engineering team. If I were to remain in a long-term operational role, it might limit my ability to pursue other impactful projects that fall too far outside of Voltron Data’s wheelhouse.

What’s Next For Me

Anyone who knows me knows that I don’t like the status quo and am always looking for ways to innovate and change things for the better. Now 38 years old, I have a much more fulfilling personal life and better work-life balance than I did in my 20s (I wrote some musings about this aspect of personal development around my 30th birthday), but I am looking forward to continue catalyzing high-impact projects to advance the data ecosystem. I plan to share more of what I’ve been thinking about lately, but for now this post has grown long enough.

The last eight years have been intense and exhilarating, and I’m extremely grateful to the early Arrow faithful who were willing to take a risk on our crazy ideas that seem a lot less crazy now. Without the early backing from Two Sigma and RStudio/Posit, and the more recent venture capital backing from Walden, GV, Blackrock, and others, we would have not been able to accomplish nearly so much. There is yet a long road ahead of us. I am excited to see where the road will lead.

Other Things: Investing and Advising Startups

Alongside my efforts as a startup founder, I have also been active as an angel investor or advisor in many startups that are working on different parts of the stack where innovation is needed. This includes Anyscale, Astral, Atoma, Bauplan, Dremio, Earthly, Fused, Hex, LanceDB, Motherduck, Neon, Quadratic, Rill Data, Storytell.ai, Sundeck, Tabular, and Union.ai. Seeing these companies develop makes me insanely optimistic about the future.

It is only possible for an individual to spend productive time directly working on so many projects at once, but I try to be as helpful as I can to other passionate founders (or prospective founders) to encourage them to work on hard problems and collaborate to disrupt the status quo.