layout	title	author	refer
plain	About me	KAWAHARA, Satoru s1311350@gmail.com	https://nymphium.github.io/aboutme.html

• Website: https://nymphium.github.io
• GitHub: https://github.com/Nymphium

Summary

I'm a full-time software engineer working at Kanmu, Inc.. My interests lie in functional programming languages and their mechanisms, especially program conversion, control operators, delimited continuation, and algebraic effects.

Engineering Skills

Languages

• OCaml
• Lua
• Haskell
• Scala
• JavaScript
• Racket
• Scheme
• Ruby

Platforms

• Linux

Other

• Git (locally, GitHub, BitBucket)

  • GitHub activities

    Please log in to see them.

    • Issues
    • Pull Requess

• Zsh

• Vim/Neovim

Main works

llix

{% gh_repo nymphium/llix %}

llix is meta-circular Lua interpreter with exception and delimited continuation mechanism. The interpreter uses CPS as intermediate representation to manage contexts. Here is a presentation.

Opeth

{% gh_repo nymphium/opeth %}

Opeth is Lua VM 5.3 Bytecode optimizer and debug tools.

Lua VM is not documented officially while the source code is opened. For implementing Opeth, I read VM's source code.

Opeth has an optimizer, bytecode visualizer, step-by-step instruction interpreter, based on global data/control -flow analysis, and, assembly-like language compiled to the bytecode.

Here is a report.

Pnyao

{% gh_repo nymphium/pnyao %}

Pnyao is a PDF management system. It adopts server-client method The server uses play framework and you can access with web browser as client.

Eff.lua & Ruff

{% gh_repo nymphium/eff.lua %} {% gh_repo nymphium/ruff %}

Eff.lua and Ruff are libraries that provide one-shot algebraic effects. These libraries are based on our research which translates one-shot algebraic effect handlers to (full, or namely stackful) asymmetric coroutines. Ruff has algebraic effects with subtyping on effects.

Detailed:

{% twicard "" https://nymphium.github.io/2019/12/22/effsub.html %}

Education

Bachelor: College of Information Science, University of Tsukuba, 04/2013 ~ 03/2018

I researched about intermediate representation about compiler for functional language. In this research I designed the intermediate language for impure functional language and optimization for them.

Bachelor thesis: 合流点を追加したコンパイラ中間言語の設計と検証

Graduate school: same as above, 04/2018 ~ 03/2020

We investigated the relationship between asymmetric coroutines and algebraic effects.

• Poster: 河原 悟, JSSST2018, ワンショットの限定継続に着目した代数的効果から非対称コルーチンへの変換.
• Article: Satoru Kawahara and Kameyama Yukiyoshi, Trends in Functional Programming 2020, One-shot Algebraic Effects as Coroutines.
• Master thesis: コルーチンを用いた代数的効果の新しい実装方法の提案

Work career

• National Institute of Advanced Industrial Science and Technology, Part-time, 09/2014 ~ 02/2015.
• AgilePoint Japan, Part-time, 05/2015 ~ 11/2018.
• HERP, inc. Part-time, 11/2018 ~ 03/2020, and full-time, 04/2020 ~ 03/2023
• Linux Development head office, Fujitsu, as an internship, 09/2015 ~ 10/2015
• Kanmu, inc. Full-time, 04/2023 ~ Present

Publications

『つくってかんたんVM-Based Interpreter』 from 『Dragon University 技術書典5』

This column focuses on how to design virtual machine-based interpreter and implement it. You can learn the formalization of the VM state and the compilation rules from the source to the instruction sequence.

The book gives an implementation of toy language.

{% gh_repo Nymphium/techbookfest5-toylang %}

{% twicard "https://dragonuniversity.booth.pm/items/1055860" https://dragonuniversity.booth.pm/items/1055860 %}

『Let's go Algebraic Effects and Handlers: from an introduction to advanced topics』

This column introduces algebraic effects and handlers by examples, containing delimited controls, and talk about the advanced topics.

{% twicard "https://dragonuniversity.booth.pm/items/1317197" https://dragonuniversity.booth.pm/items/1317197 %}

paper

• Satoru Kawahara and Yukiyoshi Kameyama, "One-shot Algebraic Effects as Coroutines," TFP 2020. [post-symposium version] [slide] [video]