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uniker.nl - Unikernels in OCamlAnnouncing segmap, a fast data structure for renamingshexen.0.1intel_hex.1.0Js_of_ocaml / Wasm_of_ocaml 6.5TIFF Inspector: an ocaml-tiff based inspector, with an in-browser OCaml playgroundOCaml 5.5.2 releasedbytream.0.4First release of spvecocaml-emcc: compile OCaml programs with their C stubs to WebAssemblyNew release of snkv-ocaml 0.3.0 — OCaml bindings for SNKV with HNSW vector searchBuilding TIFF Inspector: Exploring OCaml, TIFF Internals, and an In-Browser Playgroundstele 0.1.0: syntax-error messages for Menhir grammarsOSEC-2026-21: Str partial-match stale capture registers underflowOSEC-2026-22: Integer overflow in Unix.map_fileOSEC-2026-23: Multiple issues in MarshalOSEC-2026-24: Multiple issues in command quoting on WindowsOSEC-2026-25: Heap buffer overflow in the OCaml ~runtime_events~ consumer when parsing an oversized custom user eventOSEC-2026-26: runtime_events user event name-based type confusion

ocaml.org memory and CPU improvements; the first Tessera block processed straight into the Zarr store; a CephFS kernel bug that returned zeros for files that were fine; and day10 updates.

Forester toplevels are working well in FoCS lectures, a smooth Patch the Planet week with Trail of Bits, and drowning in security reports.

opentelemetry 0.92

A new workflow to develop and deploy unikernels

day10 reverse dependencies are live and found a dune regression; the aardvark 2017 run finished; and the v2~beta1 Zarr store was rebuilt on a grid that no longer depends on its own data.

Back to lecturing Foundations of CS, why List.tl raises, a record Tessera crowd at the CCI, and a sample of termtime meetings from Japanese AI governance to NVIDIA and samosa socials.

John Crepezzi has spent his career building tools for other programmers—at Tumblr, at Square, and then at GitHub, where he worked on the merge queue and the early versions of Codespaces. He came to Jane Street to build a code search engine for OCaml. A week into the job, ChatGPT came out, and he’s been working on AI tooling ever since. In this episode, Ron and John talk about how a three-day prototype grew into a firmwide platform for agentic coding, how AI can break the social contract around code review, and how to build tools that support both agent workflows and human understanding.You can find the transcript for this episode on our website.Some links to topics that came up in the discussion:QBasicPirates of Silicon ValleyHoogle — the Haskell API search engine that inspired the original code-search projectGitHub merge queue and CodespacesSorbet — gradual typing for Ruby; Hack — Meta’s typed PHPActive RecordBubblewrap and passt/pasta — sandboxing toolsseccomp BPFClaude Code and OpenAI Codex CLIModel Context Protocol and Agent SkillsPerfetto and magic-traceAntithesisBonsai — Jane Street’s OCaml web UI librarySignals & Threads: Language Design with Leo White