Freelancer profile translated to English.
Back to original languageAbout Guillaume
✅ Tracking & Web Analytics Specialist
🧩 Client-side & Server-side tracking expertise
🎯 Performance marketing & Ads oriented tracking
⭐ Dozens of missions on Malt – 5/5 reviews
✍️ Partner of major market server-side & CMP solutions
Specialized in tracking & web analytics, I help companies that need reliable data to guide their marketing decisions and properly activate their campaigns.
I get involved when tracking needs to be created or is already in place but causing problems: poorly measured conversions, inconsistent data in GA4, discrepancies with Google Ads or Meta, browser limitations, or the need to make data collection more reliable via server-side.
My main interventions:
🛠 Tracking setup and correction
- Tracking audit (GA4, GTM, dataLayer, events, conversions)
- Existing tracking correction (errors, duplicates, missing events)
- Complete web & mobile app tracking setup
- E-commerce tracking and lead generation
⚙️ Server-side tracking & data reliability
- Server-side tracking setup
- Event and conversion reliability
- Browser constraints and consent management
📈 Data activation & marketing performance
- Conversion tracking and activation via Google Ads, Meta
- Tracking ↔ advertising platform alignment
- Actionable data for campaign optimization
📊 Analysis, reporting & support
- Steering-oriented dashboards
- User journey and friction point analysis
- Training teams on tracking and web analytics tools
Why choose me?
✔ End-to-end approach: from data collection to activation
✔ Clear, structured, documented, and maintainable methodology
✔ Reliable, actionable data aligned with business objectives
Do you need reliable tracking to steer your performance and confidently activate your data?
👉 Let's discuss your project.
French
Native or bilingual
English
Fluent
Can work on-site
Paris (up to 50km), Lyon (up to 50km), Bordeaux (up to 50km), Marseille (up to 50km), Lille (up to 50km)
Experience
- SuperSmart S.A.
On Malt
Meta & Google Ads Tracking Reliability and Enrichment (GTM Server-Side, CAPI)FASHION AND COSMETICSApril 2026 - April 2026Paris, FranceImplementation of fixes and improvements from a prior tracking audit, with the goal of enhancing data collection quality and the reliability of advertising reporting.Work Performed
- Implementation of a GTM custom script to limit the impact of ad blockers
- Correction and reliability of Meta tracking (Pixel + Conversion API, advanced matching)
- Migration of Google Ads tags to server-side
- Enrichment of user journey tracking (transactional events and retargeting)
Deliverable
- Corrected and enriched Meta and Google Ads tracking, with an operational server-side setup.
Result
- More reliable and complete data collection, leading to improved campaign performance through higher quality conversion signals, less exposed to browser and ad blocker limitations.
- SuperSmart S.A.Tracking System Audit (dataLayer, GTM, Meta)FASHION AND COSMETICSMarch 2026 - March 2026Paris, FranceConducted a comprehensive audit of Supersmart's website tracking to evaluate data reliability, implementation quality, and consistency of reporting across marketing tools.
Work Performed
- DataLayer audit (structure, consistency, completeness of e-commerce events)
- Google Tag Manager container analysis (tags, triggers, variables, duplicates)
- Verification of event reporting in Meta (focus on data inconsistencies)
- Quality and consistency check of data across tools
- GDPR compliance audit (consent management, conditional tag triggering)
Deliverable
- Prioritized optimization backlog (Notion) including:
- identified anomalies
- corrections to implement
- improvement recommendations
- prioritization (impact / effort)
Result
A clear understanding of tracking bottlenecks and a structured action plan for rapidly improving data reliability and marketing campaign performance. - YoojoServer-side Tracking Setup for New Events (Google Ads & Meta)TECHMarch 2026 - March 2026Paris, FranceAssisted Yoojo in integrating new events related to its subscription offering, deploying server-side tracking to enable their use in advertising platforms.
Work Performed
- Server-side event implementation (Addingwell / GTM Server)
- Conversion setup in Google Ads across multiple European markets
- Event integration in Meta Ads (Conversions API)
- Harmonization of tracking across different countries
- Testing, acceptance, and data reporting validation
Result
Reliable and actionable tracking enabling these events to be used as conversions in Google Ads and Meta, with improved data quality for marketing campaign steering.
Reviews
Allan
Evolution template N8N - KAIYO MEDIA
Reviewed on 5/4/2026
Thank you Guillaume, another superb mission with you.
E
Emilie
Head of growth - SuperSmart S.A.
Reviewed on 3/26/2026
We hired Guillaume to conduct an audit of our tracking (GTM and Meta) to identify the source of several issues. Guillaume was very responsive throughout the mission, with excellent analytical skills. He quickly identified consistent blocking points and provided a clear vision for the improvements to implement. He is a reliable, structured, and trustworthy person, whom we recommend without hesitation for tracking and attribution topics. We will continue to work with him again for the implementation of these recommendations.
Recommendations
+3
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Education
- Master Grande Ecole Program ICD, E-Business and Digital Marketing option, MarketingICD Business School2022Master Programme Grande Ecole ICD, option E-Business et Marketing Digital, Marketing
- Bachelor's Degree RNCP Title "Commercial and Marketing Development Manager", Commerce / MarketingICD Business School2019BAC +3 Titre RNCP "responsable du développement commercial et marketing", Commerce / Marketing
Certifications
- Google Tag Manager Server-sideSIMMER