For the final episode of Elixir Wizards’ Season 11 “Branching Out from Elixir,” we’re featuring a recent discussion from the Software Unscripted podcast. In this conversation, José Valim, creator of Elixir, interviews Richard Feldman, creator of Roc. They compare notes on the process and considerations for creating a language.

This episode covers the origins of creating a language, its influences, and how goals shape the tradeoffs in programming language design. José and Richard share anecdotes from their experiences guiding the evolution of Elixir and Roc. The discussion provides an insightful look at the experimentation and learning involved in crafting new languages.

Topics discussed in this episode

What inspires the creation of a new programming language
Goals and use cases for a programming language
Influences from Elm, Rust, Haskell, Go, OCaml, and more
Tradeoffs involved in expressiveness of type systems
Opportunistic mutation for performance gains in a functional language
Minimum version selection for dependency resolution
Build time considerations with type checking and monomorphization
Design experiments and rolling back features that don’t work out
History from the first simple interpreter to today's real programming language
Design considerations around package management and versioning
Participation in Advent of Code to gain new users and feedback
Providing performance optimization tools to users in the future
Tradeoffs involved in picking integer types and arithmetic
Comparing floats and equality checks on dictionaries
Using abilities to customize equality for custom types
Ensuring availability of multiple package versions for incremental upgrades
Treating major version bumps as separate artifacts
Roc's focus on single-threaded performance

Links mentioned in this episode

Software Unscripted Podcast https://feeds.resonaterecordings.com/software-unscripted
Roc Programming Language https://www.roc-lang.org/
Roc Lang on Github https://github.com/roc-lang/roc
Elm Programming Language https://elm-lang.org/
Elm in Action by Richard Feldman https://www.manning.com/books/elm-in-action
Richard Feldman on Github https://github.com/rtfeldman
Lua Programming Language https://www.lua.org/
Vimscript Guide https://google.github.io/styleguide/vimscriptfull.xml
OCaml Programming Language https://ocaml.org/
Advent of Code https://adventofcode.com/
Roc Language on Twitter https://twitter.com/roc_lang
Richard Feldman on Twitter https://twitter.com/rtfeldman
Roc Zulip Chat https://roc.zulipchat.com
Clojure Programming Language https://clojure.org/
Talk: Persistent Data Structures and Managed References by Rich Hickey https://www.youtube.com/watch?v=toD45DtVCFM
Koka Programming Language https://koka-lang.github.io/koka/doc/index.html
Flix Programming Language https://flix.dev/
Clojure Transients https://clojure.org/reference/transients
Haskell Software Transactional Memory https://wiki.haskell.org/Software_transactional_memory
Rust Traits https://doc.rust-lang.org/book/ch10-02-traits.html
CoffeeScript https://coffeescript.org/
Cargo Package Management https://doc.rust-lang.org/book/ch01-03-hello-cargo.html
Versioning in Golang https://research.swtch.com/vgo-principles

Special Guests: José Valim and Richard Feldman.

Creating a Language: Elixir vs. Roc with José Valim and Richard Feldman (Elixir Wizards X Software Unscripted Podcast)

Elixir Wizards