About Hakim
French
Native or bilingual
English
Native or bilingual
Korean
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Experience
- CastelisSenior Backend DeveloperDIGITAL AND ITAugust 2025 - Today (10 months)Paris, FranceSenior Backend developer in a team building a high-throughput data processing platform for a major international organization (225+ member societies, 120+ countries).
- Event-driven microservices architecture ingesting large-scale data.
- Worked on multiple parts and owned the notification/ACK pipeline, implemented 40+ business validation rules, built the data merge engine with conflict resolution, and engineered resilience patterns for high-volume ingestion.
- NestJS, TypeScript, PostgreSQL, MongoDB, Azure Service Bus, Docker.
- Morgan & Mallet InternationalSenior Full Stack DeveloperHUMAN RESOURCESMay 2025 - February 2026 (9 months)Paris, FranceSole Full-Stack Engineer at Morgan & Mallet International, owning the entire technical stack of a production ATS serving 15,000+ users and 60,000+ registered candidates. Served as the single point of ownership for all feature development, database design, infrastructure, and production operationsSome of my missions :
- Engineered a server-side PDF resume generation system using PDFKit and Sharp, replacing the legacy Puppeteer/HTML pipeline. Eliminating headless Chrome dependency, reducing infrastructure costs by ~40%, and enabling faster PDF generation for 60,000+ candidate profiles.
- Optimized MySQL query performance for the core candidate list (60K+ records) cutting page load time from 16s to 5s (69% reduction) on the most used screen in the application.
- Automated the delivery of 400,000+ weekly newsletter emails and thousands of daily transactional emails (credentials, placement updates, interview reviews, status changes).
- Spearheaded a full codebase standardization, establishing Prettier configuration and consistent formatting across frontend and backend, reducing technical debt from years of accumulated inconsistencies and improving maintainability as a solo engineer.
- PackativeFullstack DeveloperE-COMMERCEApril 2023 - September 2024 (1 year and 6 months)Séoul, South Korea1. Lead the backend development of a new ERP product from the ground up
- Made architectural and stack decisions for scalability, keeping in mind the progression of the product to a SAAS platform (NestJS, PostgreSQL, Kafka).
- Handled backend development, DevOps, actively participated in sprint planning, maintained documentation, and implemented front-end features (React).
- Resulted in a 50% increase in sales team productivity, which in turn increased revenue for the company.
2. Implemented a data solution to create marketing dashboards- Used tools like Airbyte and Funnel to gather, regroup, sort, and analyze data from multiple sources into Google BigQuery.
- Used Looker Studio to implement dashboards for ease of use by the marketing team.
- Enhanced the marketing team's understanding of NaverAds and GoogleAds campaigns, resulting in improved marketing strategies based on real data evidence.
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Education
- Master's degree, Ingénierie informatiqueEPITECH - European Institute of Technology2017Master's degree, Ingénierie informatique
- Master's degree, Ingénierie informatique중앙대학교2016Master's degree, Ingénierie informatique