$> whoami
Gabriel de Tassigny
Staff Engineer · PHP, Symfony & WordPress · since 2012
I build and maintain web platforms for publishers and product teams, from REST APIs and headless WordPress to Gutenberg blocks and Core Web Vitals work. I'm based in Poitiers, France, and have worked remotely with teams in Dublin, London and beyond.
For employers
Hiring a senior engineer?
14 years across agency, product and media companies. Backend depth, frontend fluency, and product-owner experience.
Freelance
Need short-term help?
Limited availability for short WordPress or PHP engagements: plugins and themes, migrations and upgrades, performance audits.
$> git log --career
Experience
Staff Engineer & Product Owner · XWP
- Builds modern WordPress plugins and themes for large publishers and tech companies, with Gutenberg, React, PHP 8, Sass and TypeScript.
- Product owner for 14 of the 16 Are Media sites moved from Umbraco to a WordPress multisite (6.2 million monthly users across the programme): planned a year-long launch calendar for a team of five developers, a project manager, a QA engineer and a designer, with accessibility and Core Web Vitals kept in the green. Editors now publish in half the time.
- Product owner for a GPT-4 integration that turned unstructured restaurant reviews into structured data (JSON-LD) for search, for pennies per review.
- Improves web performance and Core Web Vitals on high-traffic sites.
- Helped define the maintenance checklist for client sites, and built an AI agent skill for the team that automates most of it: WordPress core and plugin updates, security checks and Lighthouse performance reviews.
- Writes user stories and manages and prioritizes the backlog, with internal and client stakeholders across several projects at once, in Scrum and Kanban teams.
Clients: Twitch, Are Media, Evolve Media, OFX, ButterflyMX, Good Friday Appeal
Senior Backend PHP Developer · Immediate Media
- Co-led the backend design of a new headless architecture for Immediate Media's WordPress multisite (about 100 million monthly users across its sites), launched first on the newly acquired BBC Good Food (about 50 million monthly unique users).
- Defined the API contracts for the frontend team and built three REST services with API Platform (Symfony), PHP 7.4, MongoDB and Docker: content such as recipes, per-site settings, and users' saved recipes.
- Built the WordPress side that pushes content to these services automatically whenever a post is published, edited or deleted.
- Load-tested the services with Artillery and profiled them with Blackfire to handle that traffic, on tight stakeholder deadlines.
- Set up automated testing at every level, from unit and API tests to end-to-end tests.
- Developed AWS Lambda functions with Bref for Amazon Alexa.
- Mentored and coached mid-level developers.
Senior Backend Engineer · Distilled SCH
- Built microservices with Java 8 and Spring Boot, deployed on Kubernetes.
- Worked fully remote from South Korea with three overlapping hours a day, in a Scrum team.
PHP Developer on daft.ie · Distilled SCH
- Developed and maintained daft.ie, Ireland's largest property website, through the upgrade from PHP 5.3 to 7.1.
- Led development on several medium-sized projects.
- Was the main contributor to the internal REST API, built with Slim and OpenAPI.
- Introduced best practices such as TDD, design patterns and SOLID.
Full-stack Web Developer · DirectStreams
- Built an extranet with Ruby on Rails, jQuery and Bootstrap.
- Developed REST APIs.
- Was the main maintainer of the legacy PHP 5.3 platform.
- Worked in a Scrum team of four developers.
Certifications
- Sep 2026Effective Use of Claude Code · X-Team
- Sep 2026Advanced Professional WordPress Developer · Automattic
Education
$> ls ~/projects
Projects
Headless WordPress
BBC Good Food headless platform
Co-led the backend of a headless architecture for Immediate Media's WordPress multisite, launched first on BBC Good Food and its 50 million monthly users.
Product ownership
Are Media multisite migration
Product owner for 14 of the 16 Are Media sites moved from Umbraco to one WordPress multisite, with 6.2 million monthly users in total.
WordPress plugin
Cherrylift
Pushes selected content between WordPress sites, such as staging to production, and remaps every database ID on the way.
Client work
Eutopia restaurant theme
A custom WordPress theme with block editor support for the Eutopia restaurant's website.
Client work
psychopenhars.com migration
Moved a WordPress 5.8 site built with a page builder to WordPress 7.1 and a block theme, with no broken links.
Symfony CLI
PAYG utility calculator
A command-line tool that predicts when pay-as-you-go gas or electricity credit will run out.
Frameworkless PHP
simple-blog
The blog engine that ran my blog for years, built from Composer packages without a framework.
$> git log --author=gdetassigny --all-repos
Open source
On wordpress.org
- Cherrylift – Selective Content Sync
v0.3.0Tested up to WordPress 7.1.4
Contributions
WordPress coreMay 2022
REST API: avoid a duplicated query in post collectionsFixed an extra database query when the REST API returns an empty post collection. Credited in changeset 53498.
Theme My LoginFeb 2022
Fix the login link after an AJAX password resetThe confirmation message linked to a literal "%s" instead of the login page. Merged into Theme My Login, a popular WordPress plugin.
PackagistMar 2021
simple-containerA small PHP package implementing the PSR-11 container interface.
$> tail ~/blog
Writing
- Product Managing your Side Projects
If you're like me and you couldn't find the time anymore to do programming side projects, perhaps AI can be the solution... but the experience is for sure different.
- Zensical Migration
This blog was migrated to Zensical... and boy did Claude made this easy!
$> composer show --tree
Skills
- Backend
- WordPress
- Frontend
- Data
- Testing
- DevOps
- Previously
- Languages
$> man hire
Freelance services
Available with limited capacity, for short engagements. I work in small, reviewable steps, write tests, and leave documentation so you're never locked in.
WordPress plugins & themes
Custom blocks, block themes and plugins built to WordPress coding standards, with automated tests and CI.
Example: Eutopia restaurant theme →Migrations & upgrades
Moving old WordPress or PHP sites to current versions without losing content or search ranking, rehearsed on a copy first.
Example: psychopenhars.com migration →PHP & Symfony backends
REST APIs, integrations and command-line tools with Symfony, API Platform or plain PHP.
Example: PAYG utility calculator →Performance & code audits
Core Web Vitals, slow queries and code-quality reviews, delivered as a prioritized list of fixes.
Maintenance
Ongoing updates, monitoring and small improvements for sites that need to keep running.
$> mail contact
Contact
The quickest way to reach me is by email, about a role or a short freelance engagement.