Guillaume Castagnino
Profile
Engineer graduated from IIE.
I’ve spent my entire career in software development, and over a decade specifically in cybersecurity software, from development to product management, and from legacy infrastructures to cloud ecosystems.
I am currently looking for a Product Owner position focused on technical and cybersecurity topics that bring meaning to its customers.
Experience
VulnIT — DenyAll — Rohde-Schwarz Cybersecurity — UBIKA
Paris area, FR
Over time, I saw 4 different companies with this employer.
VulnIT was a small company providing a vulnerability scanner and assessment tool. It was bought by DenyAll, a Web Application Firewall editor, to complete its portfolio. Then DenyAll saw 2 shareholders changes.
VulnIT was a small company providing a vulnerability scanner and assessment tool. It was bought by DenyAll, a Web Application Firewall editor, to complete its portfolio. Then DenyAll saw 2 shareholders changes.
Product Manager for “Cloud Protector” @ UBIKA
March 2022 – present
- Managing “Cloud Protector”, the SaaS flavor of the Web Application Firewall
- Managing the relation with “Cloud Protector” providers
- Leading in collaboration with the CTO the reboot of “Cloud Protector” using a Lean approach, with enhanced portfolio synergy
- Planning product launch and sales model for the new security modules of the “Cloud Protector” reboot
- Webinars preparation and presentation
- Product roadmap presentation in company summit and conducting workshops with customers working groups
- Product roadmap presentation in one-to-one with customers
- Commercial partnership study in collaboration with head of PM
- PO
- PM
- Kanban
- Lean
- Jira
- Confluence
Product Owner for “Cloud Protector” @ RSCS
Jan 2018 – March 2022
- Managing “Cloud Protector”, the SaaS flavor of the Web Application Firewall, in collaboration with the head of PM
- Optimizing the COGS of “Cloud Protector“, including platform migration
- Working on the MVP design of a new product targeted towards DevSecOps teams
- Acting as backup Ops on duty for “Cloud Protector”
- PO
- Scrum
- Jira
- Confluence
Senior Software Engineer @ DenyAll – RSCS
Jul 2012 – Jan 2018
- Acting as PO for “Vulnerability Manager”
- Building a platform for the Vulnerability Scanner delivered as SaaS (HA, load balancing, database redundancy…)
- Development and maintenance on the “Vulnerability Manager”, in particular improve the website crawler, adapting to the growing use of async requests (SPA)
- Development, refactoring and maintenance on the core of the Web Application Firewall
- Development and maintenance of Cloud Protector, the SaaS version of the Web Application Firewall
- Scrum organization
- PO
- Scrum
- vCloud
- C
- Java
- PHP
- Python
- Ansible
- PostgreSQL
- Vulnerability assessment
- Network
Senior Software Engineer @ VulnIT
Feb 2011 – Jul 2012
- VulnIT provides “Vulnerability Manager”, a vulnerability scanner historically as a bootable USB key
- Redesign of the product architecture: moving from a Java/Swing monolith to a n-Tier architecture with a web UI
- Deliver the product as a Virtual Machine image with an automated image build in CI
- Create “agents” to deploy in various split networks and connect them to a central Vulnerability Manager
- Virtualization
- Network
- Vulnerability assessment
- Java
- PHP
- PostgreSQL
PepperWay SCOP ARL
Paris, FR
PepperWay was a web agency we founded with former Telecom Italia colleagues
Co-founder, CTO
Oct 2009 – Feb 2011
- Building the web hosting cluster with sate of the art (at this time) HA: heartbeat, haproxy, nginx, DRBD, database redundancy
- Building the mail hosting cluster (Postfix, Cyrus IMAP) with up to date antispam technologies deployed (DKIM, SPF) and HA (storage replication with DRBD)
- Technical lead for customers projects, either e-commerce portal integration and customization (Prestashop) or custom built websites.
- HA
- Hosting
- AntiSpam
- PHP
- PostgreSQL
Telecom Italia France “Alice” — Free SAS
Paris, FR
Telecom Italia France was an Internet provider (“Alice”) that was bought by Free. No employer change.
Software Engineer @ Free SAS
Aug 2008 – Oct 2009
- Migration of the Information System, Perl/MySQL developments
- Full redesign of the B2C “Alice” customer portal (migration from PHP to Perl)
- Redesign “Alice” provisioning flows
- PHP
- Perl
- HTML
- CSS
- MySQL
Software Engineer @ TIF “Alice”
Jul 2006 – Aug 2008
- Maintenance, evolution and refactoring of the subscription interface and customer portal in relation with the B2C commercial team
- Online micro-payment service w-HA
- SOAP interfaces (IS interconnections)
- B2C recovery flow management
- Production delivery management
- Agile methodology (XP, pair programming)
- PHP
- Perl
- HTML
- CSS
- MySQL
- SOAP
IDEALX
Paris, FR
Software Engineer
Aug 2005 – Jul 2006
- “IDX::PKI” packaging for publishing
- 8 month mission for Telecom Italia France, Signup/Selfcare team: B2C customer portal maintenance, SOAP webservices design and development, w-HA payment interface
- Perl
- PHP
- SOAP
Education
IIE-CNAM/ENSIIE engineering diploma (Master’s degree)
Sep 2002 - June 2005
Specialised in advanced information systems and databases, network and security, reasoned programming, robotics and virtual reality.

- +33 6 73 85 46 69
- guillaume@castagnino.org
- cv.castagnino.org
- 21 rue Roger Henry
78210 Saint-Cyr-l’École
France - DoB: April 14, 1982
Skills
- Soft skills
- Analytical
- Active listening
- Product Management
- Agile methodology (Scrum, Kanban)
- Lean
- Value optimization
- Jira
- Technical
- Strong programming and sysadmin background (Linux)
Languages
- FrenchNative
- EnglishProfessional Working Skills – TOEIC: 875
Diplomas
- Product Focus Certified Product Manager (2021)
- PSPO I certified (2018)
- IIE-CNAM/ENSIIE Engineer (2005)
Interests
- Bike
- Photography
- OpenStreetMap
- System administration
- Piano