Freelancer profile translated to English.
Back to original languageAbout Kader
Full-Stack Developer | React - Next.js - NestJS - Node.js - TypeScript
Is your SaaS platform drowning in technical debt? Is your **legacy stack slowing down your teams**? Do you need to refactor the architecture or scale rapidly?
I step in as aFullstack Lead Devto put your applications back on solid ground: complete refactoring, progressive migration, architecture optimization, or developing new platforms from scratch to production.
I am a **full-stack developer specializing in React/Next.js (frontend) and NestJS/Node.js (backend)**, with 4 years of experience on complex multi-client SaaS platforms.
My role: designing the technical architecture, ensuring code quality, and system scalability. I work on long-term assignments (6-12 months)integrated into your teams**, or **on a fixed-price basisfor a specific scope.
During my assignments, I have supported tech SMEs and startups: refactoring legacy architecture with progressive migration,developing platformsfrom scratch to thousands of users, performance optimization (95%+), production stabilization, and team management.
On a fixed-price basis, I handle: refactoring of critical modules or features, migration to modern stacks (React/Next.js, NestJS), performance optimization and technical issue resolution, development of new features or platforms, technical audit with a prioritized action plan.
Stack: **React, Next.js, NestJS, TypeScript**, Node.js, Docker, continuous integration and deployment (CI/CD, GitLab), DevOps (AWS, Terraform), relational and NoSQL databases, automated tests, monitoring and quality tools.
My approach:deliver stable, maintainable systems aligned with your business objectives.
Let's discuss your context: I offer a quick video call to understand your needs and define a suitable intervention. Guaranteed response within 24 hours.
French
Native or bilingual
English
Fluent
Can work on-site
Paris (up to 50km), Lyon (up to 50km), Toulouse (up to 50km), Marseille (up to 50km), Bordeaux (up to 50km)
Experience
- DIGEEKLead Full-Stack Developer React | Next.js | NestJS | TypeScriptSOFTWARE PUBLISHINGOctober 2024 - December 2025 (1 year and 2 months)Toulouse, France→ Mission Objective:Technical lead for the complete refactoring of a multi-tenant event SaaS platform (10K concurrent users, 10+ enterprise clients: LNR, EPCR, Stellium). Legacy architecture (Laravel/JavaScript) unmaintainable, degraded performance.→ Achievements:Progressive migration from Laravel/JavaScript to React/TypeScript/NestJS/PostgreSQL over 18 months in 6 steps (coexistence of old/new, feature flags). Multi-tenant architecture with isolated databases per client.Performance optimization of 95%+: load times from 10-20s to milliseconds, sub-second API response times via DB indexing, query optimization, and code refactoring.Creation of infrastructure-as-code (Terraform, AWS) with a complete CI/CD pipeline: automated linting, E2E tests (Playwright), zero-downtime deployment on AWS.Management of 4 junior developers: establishing code standards, code reviews, and coaching on product-oriented thinking and optimization best practices.
- DIGEEKFull-Stack Developer React | Laravel | JavascriptSOFTWARE PUBLISHINGSeptember 2023 - September 2024 (1 year)Toulouse, France→ Mission Objective:Stabilization of the multi-tenant event SaaS platform and development of new critical features for enterprise clients.→ Achievements:Platform stabilization by resolving 200+ critical bugs (Stripe webhooks, payments), eliminating revenue loss, and reducing support escalations by 80%. Improved code quality and reduced regression bugs in production.Refactoring of the event quota allocation system (packages architecture → modular components), enabling granular configuration and unblocking 3+ enterprise clients with complex multi-component requirements.Full GDPR compliance: data export, right to erasure, consent management, anonymization with React, Laravel, and PostgreSQL.
- RingofstoryE-commerce Web Developer WordPress/WooCommerceE-COMMERCEDecember 2022 - May 2023 (5 months)Barcelone, Spain→ Mission Objective:Complete creation and management of an e-commerce platform, from web development to digital marketing.→ Achievements:Complete development and configuration of the e-commerce site: creation of the WordPress/WooCommerce architecture, development of main pages (home, about us, catalog, cart, product pages), configuration of payment gateways, product management (catalog, variations, stock), setup of logistics and delivery options.Internationalization of the platform: translation and adaptation of the site into multiple languages to expand the international market, configuration of currencies and payment options by country.Digital Marketing and SEO: development of a comprehensive marketing strategy, SEO optimization to increase visibility on search engines, creation of engaging content on social media, email marketing campaigns (Mailchimp) to retain customers.Operational Management: customer service with clear communication channels, inventory level management, collaboration with suppliers to optimize stock and delivery times.→ Technical Stack:WordPress, WooCommerce, Elementor, HTML, CSS, PHP, Mailchimp, SEO, Wordpress Plugins, Payment Gateways (Stripe)
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Education
- Expert in Information TechnologyEpitech2024Master : Expert en technologie de l'information Cursus Grande École sur 5 ans, axé sur l’apprentissage par projet, le développement de logiciels avancés, l'innovation technologique, et l'expérience professionnelle par des projets concrets.
Certifications
- AWS Cloud Quest: Cloud PractitionerAmazon Web Services (AWS)2023
- Expert in Information TechnologyEpitech2024