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Olivier CroisierOC

Olivier Croisier

Architect, Tech lead Java & Spring

€700/day
25 projects
Bordeaux, FR
15+ years
Java
Spring boot
Architect
React.js
Fullstack

Average response time: 1 hour

Freelancer profile translated to English.
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About Olivier

I am an application architect, certified Java & Spring expert, full-stack developer, and professional trainer.

For over 20 years, I have been helping my clients design and develop modern and high-performance applications, migrate and optimize their legacy systems, and improve their practices with a benevolent, rigorous, and results-oriented approach.

My Services
- Architecture and scoping of new projects
- Assembling technical stacks, carrying out POCs and MVPs
- Modernization and debt reduction of legacy systems
- Full-stack development
- Transition CTO / VP Eng. for startups
- Professional training in Java expertise

Recent Achievements
- Les Furets: audit and refactoring of the monolith into microservices deployed on the cloud, educational support for teams.
- Kubo Labs (startup): architecture and development of 2 SaaS products around Kubernetes.
- Assembling new technical stacks for Accor Hotels and Caisse des Dépôts (pensions)
- Modernization and optimization of critical applications at Evollis, RATP Smart Systems, Lifen
- Professional training for Java experts at Mirakl, France Travail DSI, Lectra

My Expertise
- Application Architecture: microservices, cloud-native, full-stack
- Java & Spring Expertise: audit, performance, and training
- Web Development (React or Angular)
- Technical Leadership: best practices, software quality, technological watch, conferences
- "Java Expertise Masterclass" Training (4.95/5, 200+ experts trained)

My Strengths
- 20+ years of experience
- Global project vision: IT, Business, Legal, Marketing...
- Autonomy, initiative, pragmatism, and results-driven culture
- Technological watch and continuous learning
- Recognized teaching skills, synthesis ability, and proposal strength
- Professional communication in French and English

Shall we discuss your projects?
Digital and IT Services

  • English

    Fluent

  • French

    Native or bilingual

Can work on-site
Bordeaux (up to 50km), Paris (up to 50km), Lyon (up to 50km), Nantes (up to 50km), Lille (up to 50km)

Experience

  • LesFurets
    Senior Application Architect
    BANKING AND INSURANCE
    August 2023 - February 2025 (1 year and 6 months)
    Paris, France
    LesFurets is an online insurance comparator.

    As an Architect reporting to the CTO, I:
    - Audited the historical monolith,
    - Proposed a transformation plan towards macro-services on Google Cloud
    - Assembled the new technical foundation (Java 21+, Spring Boot, React, Keycloak)
    - Created prototypes and example applications
    - Assisted in migrating the first features
    - Rewrote the pricing engine (which calls partner insurance companies) in a modular and optimized way
    - Participated in upskilling the teams on these technologies (mentoring, documentation, internal conferences, inviting speakers for BBLs)

    The objective was to improve application performance, facilitate maintenance (especially by external providers), and drastically reduce the Time-to-Market for new features by giving more control to the business units.
    Software Architecture Java Spring boot JPA/Hibernate MySQL React.js Typescript Google cloud OAuth2 Keycloak Redis Spring
  • Kubo Labs
    Senior Application Architect
    SOFTWARE PUBLISHING
    May 2021 - January 2023 (1 year and 8 months)
    Paris, France
    Kubo Labs publishes products (SaaS or on-premises) for installing, auditing, and monitoring Kubernetes clusters.

    As the Lead Architect and Developer, in direct contact with the founder, I:
    - Architected and developed (back & front) KuboSetup and KuboScore, which install and monitor Kubernetes clusters on major clouds or on-premises
    - Developed a custom task execution engine
    - Developed a log streaming system to the web UI
    - Integrated with Stripe for online payments
    - Participated in the development of KuboVisor (cluster supervision) and several internal tools.

    KuboSetup, KuboScore, and KuboVisor are now successfully marketed by Kubo Labs.
    Take a look at https://kuboscore.io and https://kubosetup.io, these products are cool and useful!
    Java Spring Spring boot React.js Kubernetes Google cloud HTML5 Docker Spring Security JPA/Hibernate MySQL Typescript OAuth2 Keycloak
  • CoinMarketCal
    Mobile Application Developer
    TECH
    January 2021 - March 2021 (3 months)
    Paris, France
    Through its website and mobile app, CoinMarketCal disseminates news about the cryptocurrency ecosystem and helps you track the value of your crypto portfolio.

    As a mobile developer, in direct contact with the founders, I:
    - Architected and developed the CoinMarketCal mobile application from mockups
    - Participated in the design of the REST API on AWS Lambda
    - Integrated an authentication system via Firebase

    The application is available on the Stores and is currently rated 4.6!
    React Native REST Firebase Typescript OAuth2 Amazon Web Services
Check out Olivier's experience

Reviews

5.0

Out of 21 ratings

A

Anthony

CoinMarketCal

Reviewed on 4/3/2021

Olivier collaborated with us on the complete development of our mobile application in React-Native. He quickly understood our needs and demonstrated autonomy throughout the project. We now have an application that meets our expectations; the tight deadlines and strong technical constraints were very well managed by Olivier. We would be delighted to collaborate with him again and wish him the best for the future.
AD

Account deleted

Reviewed on 12/23/2020

Olivier brought a lot to our API team at a time when we desperately needed support and an outside perspective. On one hand, his technical skills allowed us to move forward with the team's projects. On the other hand, his listening skills and good communication were invaluable to us. We highly recommend him and will call on him again if the need arises!
Show all 21 reviews

Recommendations

FU
Hadrien P.HP
FU
+1
Former user and 3 other people have recommended Olivier

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Education

  • Computer Engineering
    EFREI
    2002

Certifications

  • Sun Certified Java Programmer
    Sun Microsystems
    Java
  • SpringSource Certified Spring Developer
    Pivotal
    Spring boot Spring Spring Security
Olivier's certifications are only visible to Malt Community members

Skill set

JavaScript
Cloud
Google cloud
GDPR
SQL
noSQL
Front-End Development
Spring Security
React Native
Angular
Spring
Software Architecture
Typescript
JPA/Hibernate
HTML5
Firebase
Training
Back-End Development
PostgreSQL
Software Architecture
MySQL
OAuth2
Keycloak
Redis
Kubernetes
Docker
REST
Amazon Web Services
Hibernate
Elasticsearch
XML
Spring Cloud
Neo4j
Hadoop
Jenkins2
MongoDB
AngularJS
Apache Kafka
ExtJS
Dynatrace
JAX-WS
Apache struts
SOAP
SWT
Ext.js
GWT
Documentum
Stripes
Oracle
Mainframe
UML
WebSphere

Categories