Freelancer profile translated to English.

Description

Full Stack Developer & Custom Web Solutions Creator

Do you need a high-performance website, a business application, or an automation to save time? I design custom web solutions, from needs analysis to deployment.

I work with Next.js, React, TypeScript, Node.js, Python, and PostgreSQL for freelancers, VSEs/SMEs, and startups.

What I Offer:

Professional & Optimized Websites

Showcase sites, landing pages, and modern, responsive interfaces designed for conversion. I also handle technical SEO and Core Web Vitals.

Business Applications & SaaS

Dashboards, back-offices, client areas, management tools, authentication, databases, and third-party integrations. I develop useful and maintainable applications.

Automations & API Integrations

REST API connectors, WebSockets, scraping, document generation, data processing, bots, and workflows with Python, Node.js, or n8n.

Applied Artificial Intelligence

LLM integration, RAG, AI agents, internal assistants, semantic search, embeddings, extraction, classification, and content generation. The goal: practical AI that benefits the business.

Audit, Performance & Security

Technical audits, refactoring, optimization, secure coding, secrets management, and maintenance of existing applications.

Main Stack:

Next.js · React · TypeScript · JavaScript · Node.js · Python · Go · PostgreSQL · Prisma · MongoDB · Tailwind CSS · Shadcn/UI · REST API · WebSocket · n8n · Git · Docker · Vercel

Why Work With Me?

A single point of contact for front-end, back-end, and deployment

Direct communication and clear scope

Readable, documented solutions tailored to actual needs

Experience in SaaS, fintech, Web3, bots, and business tools projects

Registered as a France Num Activator.

Industry field of expertise

Languages

French
Native or bilingual
English
Conversational

Workplace preferences

Can work on-site

Paris (up to 20km), Amiens (up to 20km)

AuditZK
Freelance CTO — SaaS Fintech | Next.js, Performance, SEO & Security
CONSULTING AND AUDITS
November 2025 - April 2026 (5 months)
Paris, France
Context
B2B fintech SaaS platform enabling traders and fund managers to prove their performance through cryptographic mechanisms (AMD SEV-SNP secure enclaves), without exposing sensitive data.

Role & Impact
CTO mission covering the entire technical product scope: initial scoping, architecture definition, stack selection, cross-functional audits (performance, SEO, UX, security, code), and support through to production deployment.

Architecture & Stack
Definition and validation of the front-end architecture (Next.js App Router)
Selection of technologies (Clerk, Stripe, Prisma/PostgreSQL, shadcn/ui, Framer Motion)
Trade-offs based on scalability, maintainability, and fintech constraints

Performance (Core Web Vitals)
Full Lighthouse audit
Identification of bottlenecks (LCP, CLS, blocking resources)
Prioritization of optimizations to meet Google standards

Technical SEO
Implementation of a scalable SEO architecture
Implementation: dynamic metadata, JSON-LD, automated sitemap
Content structuring (exchange integration pages, knowledge base, blog)

UX, Security & Code Quality
Audit of critical user journeys
Review of security practices (API key management, AES-256-GCM encryption, sessions)
Code quality analysis (technical debt, architectural consistency)
Prioritized and actionable recommendations for the development team
Next.js PostgreSQL CTO Fintech SEO
Aspeo
Fullstack Developer | Next.js | TypeScript | React.js
PUBLIC SECTOR
September 2025 - October 2025 (1 month)
Paris, France
Mission Objective:
Completely redesign the GPF Nettoyage website under its new Aspeo identity, with a more professional design, optimized user experience, and improved SEO performance.

Achievements:
Complete redesign of the showcase website with a new visual identity, revamped architecture, and content optimized for national SEO.
Creation of detailed and categorized service pages (offices, glazing, post-construction cleaning, etc.) with targeted meta descriptions and structured tags per segment.
Implementation of JSON-LD markup to enrich Google search results (LocalBusiness, Service, WebSite schema).
Setup of 301 redirects from the old GPF Nettoyage domain to preserve natural referencing and acquired traffic.
Design of a modern and responsive interface with Tailwind CSS and Shadcn/UI, ensuring a smooth and consistent experience on mobile and desktop.
Technical SEO optimizations: semantic markup, Hn hierarchy, clean URLs, intelligent route preloading, and Core Web Vitals improvement.

Technical Stack:
Next.js, TypeScript, React, Tailwind, Shadcn/UI, Git
Next.js TailwindCSS Typescript React.js SEO
Next-Leads
Fullstack Developer | Next.js | TypeScript | React.js
TECH
September 2024 - October 2024 (1 month)
Paris, France
Mission Objective:
Develop a web application capable of automating local prospecting by identifying and analyzing target companies via Google Maps, while evaluating their web performance to optimize sales efforts.

Achievements:
Development of a geolocation-based search engine using Google Maps API to identify local businesses with name, address, website, and contact information.
Integration of Google PageSpeed Insights API to audit the performance, SEO, and accessibility of each identified website.
Development of a clear and responsive interface with Shadcn/UI and Tailwind CSS for smooth lead management, report consultation, and dynamic sorting.
Addition of a CSV export function to facilitate data reuse and analysis.

Technical Stack:
Next.js, TypeScript, Tailwind, Shadcn/UI, Google Maps API, Google PageSpeed API, Git
Next.js TailwindCSS Typescript React.js Git