Jane Street Tech Blog

@jane_street@robot.villas

OCaml, functional programming, systems, and engineering at a quantitative trading firm.

Source: https://blog.janestreet.com/feed.xml

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• Can you reverse engineer an ASIC? #Hardware #Security #ReverseEngineering

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  Aug 5, 2026

• Using OxCaml to implement type-safe reference counting between OCaml and Python #OCaml #Programming #Systems

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  Jun 15, 2026

• Formal methods and the future of programming #Programming #FormalMethods #Tech

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  Jun 7, 2026

• strace-ui, Bonsai_term, and the TUI renaissance #OCaml #Programming #TUI

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  May 26, 2026

• Using group theory to explore the space of positional encodings for attention #OCaml #AI #Math

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  Apr 22, 2026

• Can you reverse engineer our neural network? #AI #MachineLearning #OpenSource

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  Feb 24, 2026

• Results from the Advent of FPGA Challenge #FPGA #Hardware #Engineering

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  Feb 11, 2026

• I design with Claude more than Figma now #AI #Programming #Design

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  Feb 5, 2026

• Fun with Algebraic Effects - from Toy Examples to Hardcaml Simulations #OCaml #Programming #Systems

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  Jan 6, 2026

• Getting from tested to battle-tested #SoftwareEngineering #Testing #OCaml

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  Dec 3, 2025

• Advent of FPGA -- A Jane Street Challenge #FPGA #Hardware #Engineering

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  Nov 24, 2025

• What the interns have wrought, 2025 edition #OCaml #Interns #Engineering

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  Aug 27, 2025

• A Higgs-bugson in the Linux Kernel #Programming #OpenSource #Systems

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  Jul 2, 2025

• Introducing OxCaml #OCaml #Programming #Tech

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  Jun 14, 2025

• Advent of Hardcaml #OCaml #FP #Hardware

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  Mar 22, 2025

• How we accidentally built a better build system for OCaml #OCaml #Programming #OpenSource

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  Jan 24, 2025

• Developer education at Jane Street #OCaml #Programming #Education

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  Oct 4, 2024

• ICFP 2024 #OCaml #Programming #Conference

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  Aug 29, 2024

• What the interns have wrought, 2024 edition #Interns #Tech #OCaml

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  Aug 26, 2024

• Visualizing piecewise linear neural networks #MachineLearning #NeuralNetworks #DataScience

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  Jul 22, 2024

• What the interns have wrought, 2023 edition #Internship #Tech #OCaml

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  Sep 12, 2023

• Oxidizing OCaml: Data Race Freedom #OCaml #Programming #Systems

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  Sep 1, 2023

• We're sponsoring SoME3 #Tech #Sponsorship #Community

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  Jul 6, 2023

• Oxidizing OCaml: Rust-Style Ownership #OCaml #Rust #Programming

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  Jun 21, 2023

• Oxidizing OCaml: Locality #OCaml #Programming #Systems

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  May 26, 2023

• Building reproducible Python environments with XARs #Python #Reproducibility #DevOps

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  Apr 14, 2023

• What if writing tests was a joyful experience? #Testing #SoftwareEngineering #OCaml

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  Jan 9, 2023

• Accelerating zk-SNARKs - MSM and NTT algorithms on FPGAs with Hardcaml #FPGA #zkSNARKs #Hardware

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  Dec 7, 2022

• Visualizing information propagation in markets #Markets #DataViz #Finance

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  Nov 23, 2022

• Computations that differentiate, debug, and document themselves #OCaml #Programming #SoftwareEngineering

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  Nov 17, 2022

• Introducing the Jane Street Graduate Research Fellowship #OCaml #Research #Fellowship

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  Aug 30, 2022

• What the interns have wrought, 2022 edition #Internship #Tech #OCaml

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  Aug 25, 2022

• Research internships in our Tools and Compilers group #OCaml #Internship #Research

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  Mar 4, 2022

• How Jane Street Pairs Interns to Projects and Teams During the Software Engineering Internship #Internship #SoftwareEngineering #Ocaml

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  Jan 14, 2022

• Magic-trace: Diagnosing tricky performance issues easily with Intel Processor Trace #Performance #Debugging #OpenSource

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  Jan 11, 2022

• Hiring a Developer Educator #Developer #Education #Hiring

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  Oct 21, 2021

• Goodbye Core_kernel #OCaml #Systems #Programming

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  Aug 26, 2021

• What the interns have wrought, 2021 edition #OCaml #Internship #Programming

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  Aug 9, 2021

• Looking for a developer experience engineer #Engineering #Developer #Hiring

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  Jun 15, 2021

• Growing the Hardcaml toolset #OCaml #Programming #Tooling

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  Dec 1, 2020