In a different comment thread, someone mentioned the book, Category Theory for Programmers. Here's the Releases page with PDF files (click to open the Assets section). https://github.com/hmemcpy/milewski-ctfp-pdf/releases
There are several versions with code examples in Haskell, OCaml, ReasonML, and Scala. These are all typically associated with functional programming and category theory. However, category theory is a much wider and deeper subject than any specific language, and deals with mathematical objects and concepts relevant to (more or less) all of programming.
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milewski-ctfp-pdf
Bartosz Milewski's 'Category Theory for Programmers' unofficial PDF and LaTeX source
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Bartosz Milewski's 'Category Theory for Programmers' unofficial PDF and LaTeX source
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This is such a great page, i love it and came across it multiple times while studying the matter. I still would vote to learn it from Milewski though. Learning this is a…
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| 2018 | 2018-01-01 00:00:00 UTC | 2019-01-01 00:00:00 UTC | 10 | 2 | 8 |
| 2019 | 2019-01-01 00:00:00 UTC | 2020-01-01 00:00:00 UTC | 9 | 3 | 6 |
| 2020 | 2020-01-01 00:00:00 UTC | 2021-01-01 00:00:00 UTC | 4 | 1 | 3 |
| 2021 | 2021-01-01 00:00:00 UTC | 2022-01-01 00:00:00 UTC | 4 | 0 | 4 |
| 2022 | 2022-01-01 00:00:00 UTC | 2023-01-01 00:00:00 UTC | 2 | 0 | 2 |
| 2023 | 2023-01-01 00:00:00 UTC | 2024-01-01 00:00:00 UTC | 3 | 0 | 3 |
| 2024 | 2024-01-01 00:00:00 UTC | 2025-01-01 00:00:00 UTC | 3 | 0 | 3 |
| 2025 | 2025-01-01 00:00:00 UTC | 2026-01-01 00:00:00 UTC | 2 | 1 | 1 |
| 2026 (partial) | 2026-01-01 00:00:00 UTC | 2027-01-01 00:00:00 UTC | 1 | 0 | 1 |
From the project README
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Read the project’s introduction
Category Theory For Programmers
An unofficial PDF version of "Category Theory For Programmers"
by Bartosz Milewski, converted from his blogpost
series (with permission!).
Buy the book
Standard edition in full-color hardcover
print
Publish date: 12 August, 2019.
Based off release tag v1.3.0. See
errata-1.3.0 for changes and fixes since print.
Scala Edition in paperback
Publish date: 12 August, 2019.
Based off release tag v1.3.0. See
errata-scala for changes and fixes since print.
Build the book
The building workflow requires Nix. After installing
Nix, you need to enable the upcoming "flake" feature
which must be enabled manually the time being. This is
needed to expose the new Nix commands and flakes support that are hidden behind
feature-flags.
Afterwards, type nix flake show in the root directory of the project to see
all the available versions of this book. Then type nix build .#<edition> to
build the edition you want (Scala, OCaml, Reason and their printed versions).
For example, to build the Scala edition you'll have to type
nix build .#ctfp-scala. For Haskell (the original version) that is just
nix build .#ctfp.
Upon successful compilation, the PDF file will be placed in the result
directory.
The command nix develop will provide a shell containing all the required
dependencies to build the book manually using the provided Makefile. To build
the ctfp-scala edition, just run make ctfp-scala.
Contribute
Contributors are welcome to contribute to this book by sending pull-requests.
Once reviewed, the changes are merged in the main branch and will be
incorporated in the next release.
Note from Bartosz: I really appreciate all your
contributions. You made this book much better than I could have imagined. Thank
you!
Find the list of contributors on Github.
Acknowledgements
PDF LaTeX source and the tools to create it are based on the work by Andres
Raba. The book content is taken, with permission, from
Bartosz Milewski's blogpost series, and adapted to the LaTeX
format.
The original blog post acknowledgments by Bartosz are consolidated in the
Acknowledgments page at the end of the book.
License
The PDF book, .tex files, and associated images and figures in directories
src/fig and src/content are licensed under Creative Commons
Attribution-ShareAlike 4.0 International License.
The script files scraper.py and others are licensed under GNU General Public
License version 3.
Read the full README on GitHubWhat Hacker News says
40 sourcesCategory Theory for Programmers
3 points · Open discussionBartosz Milewski’s Category Theory for Programmers lectures [1] are good. Especially paired with his book [2].
I actually find that category theory is remarkably simple. At least at the level where it applies to day-to-day programming concepts. The one major benefit I got from it, was that it helped me reason about high level/abstract structure better (which helps my architectural designs/thinking).
[1] https://youtube.com/playlist?list=PLbgaMIhjbmEnaH_LTkxLI7FMa...
[2] https://github.com/hmemcpy/milewski-ctfp-pdf
In Why is it worth spending time on type theory? (2013)This is such a great page, i love it and came across it multiple times while studying the matter.
I still would vote to learn it from Milewski though. Learning this is a journey and the author of ct-illustrated is, i think, still in the middle of it.
Milewski has made that trip multiple times already. The book and his blog are great places.
https://github.com/hmemcpy/milewski-ctfp-pdf Book
https://bartoszmilewski.com/2014/10/28/category-theory-for-p... Blog
In Category Theory Illustrated: Logic (2021)I recently started reading Bartosz Milewski's Category Theory for Programmers[0] and while it's less about Haskell per se and more about the ideas behind it, I found it did a much better job at explaining Haskell to me than any other introduction I read before. At least I'm able to appreciate Typing the Technical Interview[1] now. :-)
[0]: https://github.com/hmemcpy/milewski-ctfp-pdf
[1]: https://aphyr.com/posts/342-typing-the-technical-interview
In Ask HN: What resources do you recommend for learning Haskell?Category Theory for Programmers [1] covers monoids (and other concepts). There’s a YouTube series of lectures by Bartosz Milewski too.
To get a complete intuition spending some time learning Haskell will also help.
[1] https://github.com/hmemcpy/milewski-ctfp-pdf
In A Core Calculus for Documents [pdf]Strangely similar name to the well-known 'Category Theory for Programmers'
https://github.com/hmemcpy/milewski-ctfp-pdf
In Category Theory for ProgrammingThere's this, but the programmer doesn't have to be working:
https://bartoszmilewski.com/2014/10/28/category-theory-for-p...
https://github.com/hmemcpy/milewski-ctfp-pdf
In Polynomial Functors: A Mathematical Theory of Interaction [pdf]Algebra-driven design (book):
https://algebradriven.design/
Category theory for programmers (free book):
https://github.com/hmemcpy/milewski-ctfp-pdf
In Ask HN: Math for Programmers?My method was to spend 25 years listening to colleagues mumble about Category Theory and slowly picking up the basics. Even I didn't really use Category Theory in my abstraction work. It's just that after months of effort to crack my problem, I showed my pages of work to the Category Theory folks and they were like "oh, it's simply Yoneda this and Yoneda that and your proof can be done in 4 lines.".
That said, if I had to guess at what would be effective at getting up to speed without spending 25 years, would be to checkout https://github.com/hmemcpy/milewski-ctfp-pdf Category Theory for Programmers. Milewski was one of those people who were like "Oh, it's simply Yoneda this and Yoneda that", and he figured it out all himself in parallel without seeing my proof.
But I doubt it will be like, knowing Category Theory will enable you to hav
Read the rest
e super powers for abstraction design. Rather it will be a matter of having enough mathematical tools at your disposal plus the right inspiration at the right time to realize that ones of those tools can happen to solve your abstraction programming problem you happen to be facing at some moment, in a way that is not obvious, if you are lucky. In fact, you likely have to first guess at what the right abstraction is and then fall back on Category Theory to verify the sanity of your guess.
Another category theory resource you may find interesting is Category theory for programmers by Bartosz Milewski. He also has a great video course on youtube. If you want a taste of what category theory is, you can checkout his interview on corecursive.
https://github.com/hmemcpy/milewski-ctfp-pdf
In Ask HN: Solving problems by mapping to other problems that we know how to solveThis series has some C++ examples alongside Haskell: https://bartoszmilewski.com/2014/10/28/category-theory-for-p... and acquirable as a PDF at https://github.com/hmemcpy/milewski-ctfp-pdf
In Category Theory: Lecture Notes and Online BooksYou don't need a PhD, you just need the first few chapters of [Category Theory for Programmers](https://github.com/hmemcpy/milewski-ctfp-pdf) :)
In Tricks I wish I knew when I learned TypeScriptMIT's 18.S097: Programming with Categories with Brendan Fong, Bartosz Milewski and David Spivak is great: http://brendanfong.com/programmingcats.html
All lectures from the course are in this playlist: https://www.youtube.com/playlist?list=PLhgq-BqyZ7i7MTGhUROZy...
Milewski's free book Category Theory for Programmers is a "classic" as well https://github.com/hmemcpy/milewski-ctfp-pdf
In general you can find videos on youtube of talks given at various industry functional programming conferences that often help since they start from the industry programmer point of view rather than the pure maths one.
E.g. A practical introduction to Category Theory (for Scala devs) https://www.youtube.com/watch?v=GNG3Gk9KsoI
In Infinity Category Theory Offers a Bird’s-Eye View of MathematicsBartosz Milewski's 'Category Theory for Programmers'
https://github.com/hmemcpy/milewski-ctfp-pdf/
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