# Olivier Cartier

> Freelance developer based in Lyon, France. Web and mobile development,
> infrastructure and design. This site holds his articles, his client and
> personal projects, and his HackTheBox write-ups.

The site is bilingual and statically generated. Every page below also
exists in French: swap `/en/` for `/fr/` in any link. The write-ups are
the one exception, published only in English.

## Articles

- [Pseudo-code, Framework-less - The future of code](https://cestoliv.com/en/blog/pseudo-code-framework-less-le-future-du-code/): Analysis of the impact of artificial intelligence on the developer's profession, and exploration of a new AI-based development approach: programming guided by structured pseudo-code, without a specific framework or language.
- ["👩‍💻🎉".length = 7 ??? How to count emojis with Javascript](https://cestoliv.com/en/blog/how-to-count-emojis-with-javascript/): Emojis are great, but they can be a pain to work with in JavaScript. The problem is that each emoji is actually made up of multiple UTF-16 code units, so when you try to count the number of emojis in a string, you end up with an incorrect count. I'll explain why the count is wrong, and show you how to get the right number of emoji in a JavaScript string.
- [Using IPFS for data replication](https://cestoliv.com/en/blog/using-ipfs-for-data-replication/): A complete guide to create an IPFS cluster, with docker, in order to replicate data on several machines.
- [Interview with Jim Hall for the 25th anniversary of FreeDOS](https://cestoliv.com/en/blog/25-ans-de-freedos-interview-de-jim-hall/): For the 25th anniversary of FreeDOS (a free DOS 😏), I had the chance to interview its creator, Jim Hall. Here is the transcript of this interview!

## Projects

- [Overload](https://cestoliv.com/en/projects/overload/): Strength training, running, cycling, sleep, body composition: Overload logs the sessions and does the analysis. I co-founded it and I'm the CTO.
- [Eco-Building Concept](https://cestoliv.com/en/projects/eco-building/): The website for Eco-Building Concept, an engineering consultancy. A chat answers questions about the firm and fills in the quote request with the visitor.
- [Signature d'Intérieur](https://cestoliv.com/en/projects/signature-d-interieur/): Signature d'Intérieur's whole IT stack runs through me: cloud, servers, workstations, telephony and the website.
- [HCR-12 Driver](https://cestoliv.com/en/projects/hcr-12/): A driver that steers MacTech's Hanwha HCR-12 robot arm with a 3Dconnexion SpaceMouse: the mouse's six degrees of freedom wired straight onto the arm's six axes.
- [Everest](https://cestoliv.com/en/projects/everest/): A step tracker that turns your steps into badges named after real places: the Golden Gate Bridge, a mountain pass, Everest from sea level at 1.6 million steps.
- [Trade the Scroll](https://cestoliv.com/en/projects/trade-the-scroll/): A screen-time app that answers the Instagram feed with a photo you took and one thing to do in the time you have. One payment, no subscription.
- [grove](https://cestoliv.com/en/projects/grove/): One YAML file describes a fleet of self-hosted GitHub and GitLab runners. grove makes the hosts match it, watches the jobs, and restarts whatever wedges.
- [forest](https://cestoliv.com/en/projects/forest/): Two tools: wt, a git worktree TUI that starts one AI agent per branch, and agent-spawner, a daemon that picks up Todoist tasks marked Agent Ready and dispatches them.
- [zammad-cli](https://cestoliv.com/en/projects/zammad-cli/): Create, search, reply to and close Zammad tickets from the terminal, without opening the helpdesk.
- [babak](https://cestoliv.com/en/projects/babak/): Backs up local directories, servers over SSH and WordPress sites over FTP. duplicity and GnuPG encrypt each increment, and the report lands in a Matrix room.

## Write-ups

- [Investigation - HackTheBox Machine](https://cestoliv.com/en/wu/investigation/): A vulnerability in ExifTool allows a reverse shell, and the analysis of a binary allows a privilege escalation
- [BountyHunter - HackTheBox Machine](https://cestoliv.com/en/wu/bountyhunter/): An XEE vulnerability in a form will allow us to read the connection script to the database and retrieve the identifiers
- [Explore - HackTheBox Machine](https://cestoliv.com/en/wu/explore/): A vulnerability in the Android ES File Explorer application allows us to access the smartphone's file system. Then ADB will allow us to take control of it.
- [Cap - HackTheBox Machine](https://cestoliv.com/en/wu/cap/): The traffic analysis with Wireshark will allow us to find FTP identifiers. Then it's a simple python privilege escalation that will give us the control of the machine.

## Optional

- [Articles index](https://cestoliv.com/en/blog/): every article, newest first
- [Projects index](https://cestoliv.com/en/projects/): the same projects, grouped into client and personal work
- [Write-ups index](https://cestoliv.com/en/wu/): every write-up
- [42 coursework](https://cestoliv.com/en/projects/42/): projects from the 42 curriculum in Lyon, with grades
- [Articles feed](https://cestoliv.com/en/blog/rss.xml): RSS, English articles
- [Write-ups feed](https://cestoliv.com/en/wu/rss.xml): RSS, write-ups
- [Sitemap](https://cestoliv.com/sitemap.xml): every URL on the site, both languages