HackerTube.dev

Ruby Conf 12 - Y Not- Adventures in Functional Programming by Jim Weirich

Confreaks · 65.7K views · 2012-11-11 · 53:22

Open on YouTube ↗

If playback is restricted in your region, try opening the original video. Use Mark watched to add it to your marked videos.

Overview

Jim Weirich's RubyConf 2012 talk derives the Y combinator step by step, live-coding in Ruby lambdas. It builds up an understanding of functional programming and lambda calculus from first principles.

On Hacker News

HN recommends it repeatedly as one of the best and most entertaining programming talks, and as the talk that makes the Y combinator click, even for people who do not use Ruby.

Recommended by 17 HN people across 18 months · HN mentions 2013–2026

Topics

Functional programmingComputability & complexity theoryPython, Ruby & scripting languages
Search by tags
lambda calculusrubylive codingjim weirich

What people said

peterlk · 2026-04 · Strong recommendation

Reminds me a bit of the coolest talk I ever got to see in person: [VIDEO] It’s a derivation of the Y combinator from ruby lambdas

Read the original HN comment ↗
sva_ · 2025-04 · Strong recommendation

If anyone wants this in a humorous 1 hour format, watch the legendary Jim Weirich (rip) explain it here: [VIDEO] Don't be discouraged that it is in Ruby as the concepts are completely general. Great watch even though I never coded a line of Ruby.

Read the original HN comment ↗
caseyohara · 2020-09 · Strong recommendation

On the same topic, Jim Weirich's 2012 talk "Y Not - Adventures in Functional Programming" on lambda calculus and the (little 'c') Y combinator is fantastic. [VIDEO]

Read the original HN comment ↗

Sources

Video by Confreaks, played through YouTube.

Data and selection notes

HN summaries and labels may contain AI errors. HN dates refer to discussions, not video publication.

HN Library: HackerTube export (2026-10-31) and open-index/hacker-news. Upstream summaries and classifications may contain AI errors.

Views, duration and playback status refresh separately from the published catalog. When an update fails, existing data remains visible.

Selection checks
  • SaaS & AI candidates: Topic keywords do not match
  • Editor-approved picks: Editorial review is required

Rule matches identify candidates. They do not guarantee video quality or financial results.

About the library and its sources