I was heartbroken to find out recently that Ertugrul Söylemez has passed away suddenly. Many have come forward to express their sadness about this passing and how much this has impacted the Haskell community, and how much of a loss it is for functional programming at large.

They aren’t wrong; Ertugrul was one of the faces of the friendly, warm, encouraging, patient Haskell teaching that Haskell has grown to be known for. Ertugrul was also one of the original pioneers in the implementation and theory of Functional Reactive Programming and continued to innovate even through this year. His name is now and forever will be synonymous with the “pull-based” variant of functional reactive programming. And the freenode #haskell channel and the Haskell community at large will have one less friendly face who always enjoys helping new people learn.

However, I wanted to just put some words down about his personal influence in my Haskell, Academic, and FOSS career.

When I was a new Haskeller, a lot of things confused me. But the passion of people like Ertugrul to help me understand concepts that I found interesting late into the night was one of the things that really made it worth it.

One of these lead to the creation of my first ever Haskell library, auto. auto is basically literally a direct translation of one of our conversations (and somewhat of a derivative of his own library netwire), and throughout the entire implementation process he was open to the many questions I had. And some of the features of the library (including implicit serialization) were directly his innovations put into practice.

In a slightly different context — as a new PhD student, I was told to follow wherever my curiosity lead me. One of those lines lead me to “comonadic” image processing, which was directly inspired by this unfinished article of his.

Thanks to this (and along with more help from him) I gave my first graduate research presentation. And, following from this, I submitted my work to a CFP for a conference and was accepted to give my first ever conference talk.

I’ve come along way since those times. I now have fifteen packages published on Hackage, and a few more in the pipeline. I’ve given many more research talks all over the world, as far as Ukraine. I’m no longer a fresh PhD student new to research; I’m a PhD candidate getting ready to defend my dissertation in the upcoming months. I’m still learning Haskell, but inspired by an example of a helpful Haskell attitude, I maintain a Haskell blog year after year that I hope people have, too, found helpful.

But I know I’ll always remember my roots — and the person who inspired and helped me with my first Haskell questions, my first library, and my first graduate research presentations. I can say with confidence that there is no single person who has personally influenced my Haskell career more. Ertugrul was the mentor I was blessed to have, and I know anyone who has worked with him or talked to him feels the same way.

Haskell and Functional programming lost a great innovator and educator, but I know a lot of people will say that they, like me, have lost a great friend and mentor.

Thank you.