Jean-Sébastien Techer
Jean-Sébastien Techer
Fullstack Developer & DevOps Expert • Founding Engineer, part-time CTO

15+ years of Fullstack, DevOps & Cloud expertise

FullstackDevOpsIS MigrationSovereign cloudScalewayReact/React NativeNode.js/NestJSDocker/Kubernetes

My achievements

15+

Years of experience

6+

IS migrations

2M€+

Transactions/month

100+

Mentored students

Professional Journey

My evolution: Fullstack Developer → DevOps & Cloud Expert → Founding Engineer, part-time CTO

Identity & Policy Gateway for AI Agents

HODOR

Senior Software Engineer

April 2026 - Present

Development of the HODOR platform (hodor.ai): identity, policy, and guardrail layer for AI agents. Gateway securing agent ↔ SaaS interactions (GitHub, Notion, Linear, Supabase, Stripe, Vercel) via MCP, with unique identity, fine-grained permissions, and full audit trail. As part of this mission, migration of the IS to Scaleway (sovereign cloud).

Technologies:

TypeScriptNode.jsNestJSReactMCPPostgreSQLOAuth2ScalewayTerraform

Impact : Centralized control point to govern and audit the AI agent ecosystem; IS operated on Scaleway

Scalable Payment Gateway

SGW

Lead Software Engineer

August 2024 - March 2026

Design and leadership of a payment gateway processing over 30,000 monthly subscriptions for a volume exceeding 2 million euros in transactions per month.

Technologies:

GoNode.jsNestJSTypeScriptRedisBullMQPostgreSQLDynamoDBAWSTerraform

Impact : Robust and secure unique API with highly available and monitored architecture

Doctors / Patients / Pharmacists Platform

Pictaderm

Founding Engineer

October 2024 - March 2025

Founding Engineer of a MedTech matching platform for doctors, patients and pharmacists: fullstack web + mobile design and development, security gates and traceability. Architecture pivot away from Supabase to NestJS, PostgreSQL and encrypted object storage to meet health-data / HDS requirements. First ship in ~12 weeks.

Technologies:

NestJSReactReact NativePostgreSQLPrismaHDSS3

Impact : MedTech platform in production, HDS-compliant, after a controlled architecture pivot

Mobile App & Technical Direction

Hili'UP

Fullstack Developer & part-time CTO

September 2024 - January 2025

Part-time CTO technical leadership and fullstack development of a mobile application: product roadmap, delivery and architecture choices. Infrastructure migration to a serverless architecture to lower ops load and industrialize scaling.

Technologies:

React NativeNode.jsDockerAWSServerless

Impact : Mobile app shipped under technical direction; infra moved to serverless

Featured Projects

A selection of my most significant achievements

Hodor.ai — AI Agents Gateway

Platform • 2026

Identity, policy and guardrails platform for AI agents (MCP): gateway, fine-grained permissions, audit. Includes migration of the IS to Scaleway (sovereign cloud, Terraform).

Technologies:

TypeScriptNestJSMCPPostgreSQLScalewayTerraform

Impact: Governed agent ecosystem in production; IS on Scaleway

SGW Payment Gateway

Backend • 2024

Fullstack Developer & DevOps Expert: Scalable payment gateway processing over 30,000 monthly subscriptions for a volume exceeding 2 million euros in transactions per month. Cloud architecture and DevOps.

Technologies:

GoNode.jsNestJSTypeScriptRedisBullMQPostgreSQLDynamoDBAWSTerraform

Impact: Robust and secure unique API with highly available architecture

Pictaderm — MedTech Platform

Mobile App • 2024

Founding Engineer: web + mobile app for doctors / patients / pharmacists, dermatological diagnosis and follow-up. Architecture pivot (away from Supabase) to NestJS + PostgreSQL + encrypted storage for HDS compliance. First ship in ~12 weeks.

Technologies:

React NativeNestJSPostgreSQLPrismaHDS

Impact: Connected health solution in production, HDS-compliant

Fullstack Developer, DevOps & Cloud Expert + Team Management

I combine technical expertise (Fullstack Developer, DevOps Expert, Cloud, Mobile MVP) and team management. A double competency that makes the difference for your projects.

Engineering Manager

Technical Team Management
Management of Fullstack developer, DevOps, and Cloud teams. 1-on-1, coaching, recruitment, performance
Process & Organization
Agile/Scrum, planning, roadmaps, OKRs for Fullstack, mobile MVP, and Cloud projects
Communication
Stakeholders, reporting, escalation, negotiation on technical projects
Product & Technical Vision
Business alignment, priorities, Fullstack, DevOps, and Cloud tech strategy

Founding Engineer, part-time CTO — Fullstack Developer & DevOps Expert

Fullstack & Cloud Architecture
Fullstack developer: Microservices, cloud architecture, scaling, security. Including mobile MVP
Code Quality & Mobile MVP
Clean Code, 12 Factors, testing, CI/CD for web, mobile apps and mobile MVP
DevOps & Cloud Expert
Monitoring, observability, performance, cloud infrastructure, CI/CD
Fullstack & DevOps Technical Mentoring
Code review, pair programming, Fullstack developer and DevOps training

Why is this combination valuable?

Fullstack Developer, DevOps & Cloud Expert + Team Management: Most Engineering Managers no longer code, most Tech Leads don't manage.
I combine both: technical expertise (Fullstack, DevOps, Cloud, Mobile MVP) and team management.
This allows me to make informed technical decisions while effectively managing teams and deadlines.

⚡
Fast Decisions
No need to translate between tech and business
🎯
Guaranteed Delivery
I code AND I manage the team
🚀
Efficient Scaling
Architecture + team + process

Technical Skills

My technical expertise organized by categories

Frontend

React95%
React Native95%
VueJS85%

Backend

Node.js95%
NestJS90%
Go90%
Python88%
Symfony85%

Database

PostgreSQL92%
MongoDB85%
DynamoDB80%
Redis88%

DevOps

Docker95%
Terraform85%
Ansible85%
Kubernetes80%

Infrastructure

Envoy80%
GCP80%

Client Testimonials

What my clients and collaborators say

"Jean-Sébastien is an accomplished fullstack developer: front, back and even devops with a real infra sensitivity that allowed him to set up a solution close to the highest standards in terms of security for health data. Redoubtably effective, he knows how to develop the first version of a project with a high level of autonomy and maximum efficiency."

Guillaume Lebourgeois
CTO, Adostin
Connected health solution

"Thank you Jean Sébastien for this good collaboration. He perfectly integrated into a complex project and a team of 15 people working remotely."

Yvon-Artelia Digital
Development team
Complex multi-team project

"Jean Sébastien led many successful projects at Scaleway. Passionate about development, he is a serious, pragmatic, versatile and efficient developer. He is proactive on technical choices and problem solving."

Antoine Courouble
Former CIO, Scaleway
Cloud projects & team management

Education & Certifications

My continuous training journey

Tech Lead / Level 7 Title

OpenClassrooms

2019 • Master's degree

Complete training in technical leadership and team management

Web Developer

OpenClassrooms

2016 • Associate degree

Training in modern web technologies and best practices

Methodologies & Approaches

Methods I apply to guarantee quality and efficiency

Agile/ScrumSRE VisionCloud ReadyDevOpsProduct FirstClean Code12 FactorsBusiness Focus

Ready to collaborate on your next project?

Whether for an MVP, an architecture redesign or team management

Response within 2h • Free audit • Guaranteed delivery • 2-week trial period