Introduction to Roc Programming Language by Richard Feldman

May 8, 2024

Richard Feldman introduces the Roc programming language as a fast, friendly, and functional language in active development, featuring a small ecosystem. He covers Roc’s syntax, emphasizing assignments,, and lambdas, while highlighting its purely functional nature. Roc’s error handling and type inference capabilities are discussed, showcasing how the compiler infers types and prevents errors from spreading. Roc supports different workflows, accommodating both low ceremony and robust error handling approaches. The platform design allows for standalone executable builds with secure IO primitives, enabling safe execution of scripts downloaded from the internet. Despite being a work in progress with occasional compiler crashes, Roc has inspired Richard, particularly for projects beyond front-end web development.

Introduction to Roc Programming Language: A comprehensive overview

Richard Feldman’s presentation on the Roc programming language offers a detailed exploration for both newcomers and seasoned developers alike. In this overview, we’ll delve into the key highlights of his presentation, covering Roc’s syntax, error handling, type inference capabilities, web server functionalities, platform design, and its current state.


Syntax and introduction to Roc

Richard kicks off the presentation by introducing Roc as a fast, friendly, and functional language still evolving within a small ecosystem. Despite some compiler bugs, Roc promises a robust development experience. He provides a glimpse into Roc’s syntax, touching upon assignments,, and lambdas, while emphasizing its purely functional nature.


Error handling and type inference

Moving forward, Richard dives into Roc’s error handling and type inference mechanisms. He showcases how Roc’s compiler infers types and prevents errors from spreading, enhancing program reliability. Developers can start with minimal ceremony and gradually adopt more robust error handling approaches as needed.


Web server capabilities

Richard demonstrates Roc’s capabilities in web server development, illustrating the creation of a basic web server and handling HTTP requests. He emphasizes Roc’s ability to handle JSON data efficiently, showcasing its statically-typed nature in action.


Robust error handling

A significant portion of the presentation revolves around Roc’s robust error handling mechanisms. Richard highlights Roc’s ability to handle errors granularly, ensuring that errors are caught and addressed effectively without propagating through the program.


Platform design and security

The discussion shifts towards Roc’s unique platform design, focusing on building standalone executables with secure IO primitives. Richard explains how Roc’s platform ensures safe execution of scripts downloaded from the internet, prioritizing security and sensibility in coding practices.


Current state and future prospects

Richard concludes by discussing Roc’s current state, acknowledging its status as a work in progress with occasional compiler crashes. Despite these challenges, Roc has inspired developers like Feldman, offering a promising alternative for various use cases beyond front-end web development. He encourages developers to start with small projects and welcomes contributions to further enhance Roc’s capabilities.



Richard Feldman’s comprehensive overview of the Roc programming language provides valuable insights into its syntax, error handling, web server functionalities, platform design, and future prospects. As Roc continues to evolve, it presents an exciting opportunity for developers seeking a fast, functional, and secure programming language for diverse projects.


Additional resources

Check out more from the MeetUp Func Prog Sweden. Func Prog Sweden is the community for anyone interested in functional programming. At the MeetUps the community explore different functional languages like Erlang, Elixir, Haskell, Scala, Clojure, OCaml, F# and more.