Monday 11 December 2023

Advent Of Code and Alteryx

 Image generated with the assistance of AI [1]

It is now just over 5 years since I tweeted the below on X (Twitter):

and, pulling that tweet up to write this post, I realise I actually got very little engagement. But fast forward 5 years and at the time of writing (Day 9) over 100 people have solved at least one of this year's problems using Alteryx; there is a very active WhatsApp group (that I struggle to keep up to date with!) and you can get a shiny Advent Of Code badge on the Alteryx community!

Image from Alteryx community [2]

What is the Advent Of Code?

But what is this Advent Of Code (AoC)? And why do we care that people are solving it in Alteryx?

Advent Of Code was created by Eric Wastl in 2015[3] and is "an annual set of Christmas-themed computer programming challenges that follow an Advent calendar."[4] So not particularly data problems or designed to be solved by Alteryx, people solve them in all sorts of computer languages. Over the years I have solved them in many languages including Python, R, Scala and Rust. For myself as a software engineer I find it an interesting way of playing with a new language, learning its capabilities, strengths and weaknesses. And also as a way of seeing how other people write code.

So why solve them in Alteryx? Well the simplest answer is why not? Doing strange things with Alteryx has been something I have enjoyed doing for many years. 

The second answer is because I can :) (Sometimes...) What I noticed back in 2018, and has held true since, is that Alteryx is very good at solving the early days of the AoC challenges. And this is in many ways due to how Eric designed the puzzles: the input to every problem is always a single text file and the answer (or output) is always a single integer. (Well two integers, as each day has two parts.) So however complex the puzzle, all of the input is always contained in a single text file, that has to be parsed into its parts, before you move on to solving the actual puzzle. And if there is one thing that Alteryx can do very well, it is parsing text files!

Where things become interesting is as the problems get more complex, we begin to run into the limits of Alteryx as a programming language. Which leads me to my next interesting question:

Is Alteryx A Programming Language?

This is an interesting question. It is certainly not marketed as a programming language. Typically we think of a programming language being made up of code and Alteryx is talked about as being "code free".

But in reality: yes, Alteryx is a programming language.

As the user drags and drops tools on to the canvas they are building up an xml document that represents the data transformation that they have defined. That xml (or code) is then executed by the Alteryx engine.

If we are going to be more specific we can say that Alteryx is a "Visual Programming Language" and it is a "Domain Specific Language". The domain in question being data analytics. And it is this domain which brings certain limits to the language which makes some of the Advent Of Code problems more challenging...

But Isn't Alteryx Turing Complete?

Well yes. I think it was Steve Ahlgren who famously stated that Alteryx was Turing complete if you used a rock to hold down the run button. But being Turing complete isn't actually that interesting for real world applications. My 10 year old daughter with a pen and a pad of paper is Turing complete. As is Excel [5]. As is "Magic: the Gathering" [6]. But none of those are going to be particularly good for writing arbitrary computer programs in. Turing completeness is a useful concept when we are looking at the theory of what computer algorithms can or can not do. It is not a great measure for what they can practically do with a reasonable amount of computing power and time.

Where are the limits of the Alteryx language?

I think there are two major limitations that you run into in trying to solve Advent Of Code problems in Alteryx: Types and Loops.

(Please add in the comments if you can think of more.)


The only data type in the top level Alteryx language is the data table. This makes a lot of sense given our previous statement that is a Domain Specific Language for manipulating data, but does limit its capabilities when trying to use it as a more general purpose language. Of course within the data table there is a rich type system and usually you can work within the table to represent the data variables you need.


I think this is the big one, and usually the point where I give up on AoC in Alteryx for the year. Alteryx does have the concept of loops in the form of batch macros (loosely equivalent to a FOR loop) and iterative macros (loosely equivalent to a DO WHILE loop), but these can be difficult to configure (especially if you have some complex data variables you are manipulating in tables. But more of a problem on the practicality front they can take a long time to execute. I have built AoC solutions that have taken over 24 hours to execute. Generate rows can be a good way to avoid a macro solution and simulate a loop, but can sometimes bring different data size issues.


Day 9 is usually about as far as I get with Advent Of Code and Alteryx, before the busy-ness of family life and December overtakes life. (And having departed Alteryx last week, my trial Alteryx license will soon run out). So next year I will be completing AoC in a different language.

Good luck to everyone still playing!

Merry Christmas and a Happy New Year



[1] Image Creator from Microsoft Designer (

[2] Advent of Code 2023 (2023).

[3] Advent of Code 2023 (2023).

[4] Wikipedia contributors (2023) Advent of Code.

[5] Couriol, B. (2021) 'The Excel Formula language is now Turing-Complete,' InfoQ, 2 August.

[6] Churchill, A. (2019) Magic: The Gathering is Turing Complete.

Tuesday 5 December 2023

The mountains are calling and I must go


Image generated with the assistance of AI [1]

...and I will work on while I can, studying incessantly." - John Muir, 1873 [2]

Some personal news to share with you all today: after almost 13 years working at Alteryx, the time has come for me to move on to new adventures.

My last day was December 1st 2023.

Thank Yous

I have to start with the thank yous in case some of you don't make it to the end. And after 13 years there is a lot of people to thank, so apologies in advance to all the people I miss.

My biggest thank you has to go to Ned Harding for not only creating the fantastic piece of software that is Alteryx Desktop Designer, but for giving me the opportunity to be a part of building it. Thank you for your mentorship and friendship over the years. And of course thank you to Dean Stoecker and Libby Duane Adams for creating this place I have called home for so long. It has been an amazing journey!

My First Alteryx

This is a hard thank you list to write, as Alteryx has changed so much since when I started to when I left, that in many ways it feels like I have worked for multiple different companies. Each with its own people and styles. And suddenly I am leaving all of them at once, even though some of the earlier incarnations are long gone.

I would like to thank all of the fine folk of the Boulder office and my "first Alteryx" for making myself and my wife so welcome when we first moved there back in 2011. There are too many to name you all but they include: Linda Thompson, Amy Holland, Tara McCoy Giovenco, Rob McFadzean, Rob Bryan, Catherine Metzger, Margie Horvath, Damian Austin, Nathalie Smith, Hannah Keller, Wendy Chow and Kim Hands.

The Spirit Of Alteryx

The next set of thank yous go to the people who embody the "Spirit of Alteryx" starting with Steve Algren and Linda Thompson (one of whom I think coined this phrase) for everything you do to keep that magic of what makes Alteryx special continue to burn. Especially in recent years at the Inspire conference and working with the ACEs. Which brings me to the ACEs: one of the most amazing groups of people I have the pleasure to know in my life. Some of my happiest moments have been in a room with these people, brainstorming problems and ideas of how to solve complex problems and make the product better. You are too many to call out individually, but I do have to thank Mark Frisch my team mate for the CReW macros and someone who embodies the Spirit of Alteryx in all that he does.


I will end with some thank yous for a few of my favourite projects over the years and for the good people who were there with me:

  • The CReW macros - The project that I call my greatest success and failure at Alteryx - Mark Frisch, Chris Love, Joe Mako and Daniel Brun
  • The AMP engine - The second generation massively multi-threaded Alteryx engine. One of the projects that I am most proud of. - Ned Harding, Scott Wiesner, Chris Kingsley, Sergey Maruda, Roman Savchenko and all of the amazing C++ engineers who have contributed to that project.
  • The Black Pearl project - The one that got away... (Naming a project after a cursed pirate ship was perhaps in hindsight asking for trouble, but I still think in a parallel universe this ship still sails on and would have been a great feature.) - Boris Perusic, David Vonka and all of the good crew who sailed that short but exciting voyage with us.
  • Control Containers - My swan song. Another one that I wasn't sure would make it out at times, but I am so happy that it did. My last big contribution to desktop designer. - The one and only Jeff Arnold who pulled it over the line with me.

Apologies again for all the people who I have not being able to mention by name. I thank all of you for your contributions over the years.

My Journey

It was over 15 years ago that I first discovered a product that I then called Alteryx made by a company called SRC, and that you would now call Desktop Designer made by a company called Alteryx. And it is fair to say that product has been one of the great loves of my life. If you have ever seen the film Good Will Hunting, there is a scene in it where Matt Damon's character (Will) is trying to explain to Mini Driver's character (Skylar) how he is so good at Maths:

Will : Beethoven, okay. He looked at a piano, and it just made sense to him. He could just play.
Skylar : So what are you saying? You play the piano?
Will : No, not a lick. I mean, I look at a piano, I see a bunch of keys, three pedals, and a box of wood. But Beethoven, Mozart, they saw it, they could just play. I couldn't paint you a picture, I probably can't hit the ball out of Fenway, and I can't play the piano.
Skylar : But you can do my o-chem paper in under an hour.
Will : Right. Well, I mean when it came to stuff like that... I could always just play. [3]

Well for me, when it came to Alteryx, I could always just play.

And what a journey that has taken me on. I have gone from a data analyst to a principal software engineer. From an individual contributor to a director of over 50 engineers. From my first Inspire, feeling absolutely terrified talking in front of 20 people to the London Inspire at Tobacco Dock, closing out the conference on the main stage with Ned.

I have laughed, cried (only once in the office), grown personally and professionally in more ways than I could ever have imagined, and made some life long friends who I am so happy are part of my life.

Please don't be a stranger. Always happy to meet up for a beer if you are ever in London, or jump on a zoom call and talk data and analytics.

Where Next?

Whenever someone posts a leaving post on LinkedIn there is always the comment that asks "where are you off to"? Well good readers that is another book that is yet to be told, and one that you will have to wait a little while to start reading. But for now let us say I am excited for a new adventure, and I will leave you with the Haiku from Alteryx past:

Chaos reigns within.

Reflect, repent, and restart.

Order shall return. [4]