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Generating Static Websites the Functional Programming Way Xavier Van de Woestyne (Tarides) ABSTRACT Static site generators like Jekyll, Zola, and Hugo are effective, but fall short for complex sites like personal encyclopedias, wikis, or sites with rich content. Features like backlinks and transclusions require richer context and efficient builds. This talk explores the theory behind static site generation (as a case of build systems) and shows how to implement advanced features inspired by Project Xanadu using YOCaml, a static site framework based on functional abstractions (such as strong profunctors) in OCaml. Session page: https://fun-ocaml.com/2025/static-websites-functional-programming/ Connect with FUN OCaml: Twitter: https://x.com/FunOCaml Bluesky: https://bsky.app/profile/fun-ocaml.com #ocaml --- Big Thanks(TM) go to our generous sponsors who made FUN OCaml possible! * Octra Labs - https://octra.org/ - Platinum Sponsor * Ahrefs - https://ahrefs.com/ - Platinum Sponsor * Dialo - https://dialo.ai/ - Gold Sponsor * LexiFi - https://www.lexifi.com - Bronze Sponsor * Jane Street - https://www.janestreet.com/ - Bronze Sponsor * LightSource - Volunteer / Organizer Commitment * Tarides - Volunteer / Organizer Commitment

Generating Static Websites the Functional Programming Way Xavier Van de Woestyne (Tarides) ABSTRACT Static site generators like Jekyll, Zola, and Hugo are effective, but fall short for complex sites like personal encyclopedias, wikis, or ...

From OCaml 4 to 5 and from Parmap to Effects: A legacy code transition story SPEAKERS Nathan Taylor (Semgrep) Nat Mote (Semgrep) ABSTRACT OCaml 5's support for shared memory parallelism and effects-based concurrency opens up new ways for developers to build new OCaml programs for modern hardware, but it isn't trivial to migrate existing software to this new world. We've spent the last few months porting a large (~3MM LoC) OCaml codebase from process-based parallelism to multi-domain Eio, and learned a lot along the way. In this talk, we'll discuss the fundamentals of shared-memory parallism, our incremental migration approach which used a combination of static and dynamic analysis, the pitfalls (both expected and unexpected) that we encountered along the way, and some lessons that others can adopt for their own journey. Session page: https://fun-ocaml.com/2025/from-ocaml-4-to-5/ Connect with FUN OCaml: Twitter: https://x.com/FunOCaml Bluesky: https://bsky.app/profile/fun-ocaml.com #ocaml --- Big Thanks(TM) go to our generous sponsors who made FUN OCaml possible! * Octra Labs - https://octra.org/ - Platinum Sponsor * Ahrefs - https://ahrefs.com/ - Platinum Sponsor * Dialo - https://dialo.ai/ - Gold Sponsor * LexiFi - https://www.lexifi.com - Bronze Sponsor * Jane Street - https://www.janestreet.com/ - Bronze Sponsor * LightSource - Volunteer / Organizer Commitment * Tarides - Volunteer / Organizer Commitment

From OCaml 4 to 5 and from Parmap to Effects: A legacy code transition story SPEAKERS Nathan Taylor (Semgrep) Nat Mote (Semgrep) ABSTRACT OCaml 5's support for shared memory parallelism and effects-based concurrency opens up new ways...

This talk breaks down a CTF puzzle Corwin de Zahr designed a few years back that involves finding problems and vulnerabilities within the OCaml runtime. Read the full transcript here: https://www.janestreet.com/tech-talks/hacking-ocaml/

This talk breaks down a CTF puzzle Corwin de Zahr designed a few years back that involves finding problems and vulnerabilities within the OCaml runtime. Read the full transcript here: https://www.janestreet.com/tech-talks/hacking-ocaml/

Fun OCaml 2025 is a 2 days open source hacking event dedicated to OCaml enthusiasts and professionals around the globe! This is day 1 and we're live-streaming all the presentations! For the schedule, see https://fun-ocaml.com#schedule.

The OCaml community participated in the May 2025 round of Outreachy internships. Two interns worked on a range of projects including [Claudius](https://github.com/claudiusFX/claudius) and [Dune](https://github.com/ocaml/dune). This meeting was ...

Rust promises to empower everyone to build reliable software, but its unique features create steep learning curves. In this talk, Will Crichton presents four years of research into evidence-based tools that help both novices and experts work more effectively with Rust's complexity, including: - Ownership visualization: Interactive diagrams showing permissions (read/write/own) that help students understand borrowing better than rule-based explanations - Trait debugging: A graphical tool for navigating complex trait inference trees when compiler errors become unreadably long - Program slicing: Using Rust's type system to automatically highlight only code relevant to specific variables All tools discussed are open source and available for use.

Jane Street is an electronic trading firm that uses low latency trading systems built in OCaml to provide liquidity to financial markets worldwide. In December 2022, after nearly a decade of development, OCaml 5.0 was released with OCaml’s first multi-core capable runtime. This was an exciting milestone, finally making it possible to write shared-memory parallel programs in OCaml. The new runtime was designed to be easy to adopt: it didn’t disturb OCaml’s FFI, and performance was meant to be only a few percentage points slower in single-core mode. Despite those promising beginnings, switching to runtime-5 within Jane Street was harder than we expected. Indeed, we've only just switched to it this year, after 2.5 years of research and engineering effort. This talk will give an overview of the problems we ran into, and what we learned from the process, including some new ideas that solved some very old problems in the design of OCaml's GC. Read the full transcript here: https://www.janestreet.com/tech-talks/the-saga-of-multicore-ocaml/