https://www.youngju.dev/blog 천천히 올바르게. AI Researcher & DevOps Engineer Youngju's tech blog. GPU/CUDA, LLM, MLOps, Kubernetes AI workloads, distributed training, and data engineering. ko fjvbn2003@gmail.com (Youngju Kim) fjvbn2003@gmail.com (Youngju Kim) Sat, 16 May 2026 00:00:00 GMT https://www.youngju.dev/blog/culture/2026-05-16-modern-ocaml-2026-ocaml-5-3-multicore-effect-handlers-dune-opam-mirageos-rescript-melange-jane-street-deep-dive.en https://www.youngju.dev/blog/culture/2026-05-16-modern-ocaml-2026-ocaml-5-3-multicore-effect-handlers-dune-opam-mirageos-rescript-melange-jane-street-deep-dive.en After OCaml 5.0 GAed in December 2022 with multicore plus effect handlers, the 5.x line stabilized through OCaml 5.3 in January 2025, putting OCaml back on the table as a serious industrial language. This guide maps the 2026 OCaml ecosystem in a single read: the Dune build system and Opam package manager, MirageOS unikernels, the JS-compilation branches (js_of_ocaml / ReScript / Melange / Reason), Eio effect-based concurrency vs Lwts legacy, Cohttp and Dream for the web, Tezos (XTZ) blockchain in production, Hack and Flow at Meta, Async at Jane Street, the massive Jane Street codebase, and the KAIST PL lab plus Kyoto University PL lab on the academic side. Sat, 16 May 2026 00:00:00 GMT fjvbn2003@gmail.com (Youngju Kim) ocamlocaml-5-3multicore-ocamleffect-handlersduneopammirageosunikerneljs-of-ocamlrescriptbucklescriptmelangereasoneiolwtcohttpdreamtezoshack-metaflowasyncjane-street2026deep-diveenglish https://www.youngju.dev/blog/culture/2026-05-16-modern-ocaml-2026-ocaml-5-3-multicore-effect-handlers-dune-opam-mirageos-rescript-melange-jane-street-deep-dive.ja https://www.youngju.dev/blog/culture/2026-05-16-modern-ocaml-2026-ocaml-5-3-multicore-effect-handlers-dune-opam-mirageos-rescript-melange-jane-street-deep-dive.ja 2022年12月にMulticoreとEffect Handlersを搭載したOCaml 5.0がGAし、2025年1月の5.3まで安定化を経て、OCamlは再び産業言語として真剣に議論される位置に戻ってきた。Dune ビルドシステムとOpam パッケージマネージャが作る合理的標準、MirageOSのユニカーネル、js_of_ocaml/ReScript/Melange/Reasonというフロントエンド分岐、Eioが持ち込むeffect ベースの並行性とLwtの遺産、Cohttp/Dreamの Web、Tezos(XTZ)ブロックチェーンの事例、MetaのHackとFlow、Jane Streetの巨大なOCamlコードベース、KAIST PL labと京都大学 PL labというアカデミア — 2026年のOCamlエコシステムを一冊にまとめる。 Sat, 16 May 2026 00:00:00 GMT fjvbn2003@gmail.com (Youngju Kim) ocamlocaml-5-3multicore-ocamleffect-handlersduneopammirageosunikerneljs-of-ocamlrescriptbucklescriptmelangereasoneiolwtcohttpdreamtezoshack-metaflowasyncjane-street2026deep-dive日本語 https://www.youngju.dev/blog/culture/2026-05-16-modern-ocaml-2026-ocaml-5-3-multicore-effect-handlers-dune-opam-mirageos-rescript-melange-jane-street-deep-dive https://www.youngju.dev/blog/culture/2026-05-16-modern-ocaml-2026-ocaml-5-3-multicore-effect-handlers-dune-opam-mirageos-rescript-melange-jane-street-deep-dive 2022년 12월 Multicore + Effect Handlers를 가져온 OCaml 5.0의 GA 이후, 2025년 1월 5.3까지 안정화되며 OCaml은 다시 한 번 주류 산업 언어의 후보로 돌아왔다. Dune 빌드 시스템과 Opam 패키지 매니저가 만든 합리적 표준, MirageOS의 유니커널, js_of_ocaml과 ReScript/Melange/Reason의 프런트엔드 분기, Eio가 가져온 effect 기반 동시성과 Lwt의 유산, Cohttp/Dream의 웹, Tezos(XTZ)의 블록체인 사례, Meta의 Hack과 Flow, Jane Street의 거대한 OCaml 코드베이스, KAIST PL lab과 京都大学 PL lab의 학계 — 2026년 OCaml 생태계를 한 권으로 정리한다. Sat, 16 May 2026 00:00:00 GMT fjvbn2003@gmail.com (Youngju Kim) ocamlocaml-5-3multicore-ocamleffect-handlersduneopammirageosunikerneljs-of-ocamlrescriptbucklescriptmelangereasoneiolwtcohttpdreamtezoshack-metaflowasyncjane-street2026deep-dive