ROIMVP in prod in 30–45 days — without hiring a senior

≈ €75–105k saved over 10 monthsfrom €4,500/ month (≈ 1/3 of a fully loaded senior's cost)

Agents + iASSET gates · dev & cloud included · pipeline live in 1 week

Calculate my ROI
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

Platform2026

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

Backend2024

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 App2024

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

2019Master's degree

Complete training in technical leadership and team management

Web Developer

OpenClassrooms

2016Associate 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