+++ title = 'Professional experience' description = 'Olivier Perceval’s experience, skills and selected work.' +++ ## Olivier Perceval Independent consultant taking over and modernising business applications, based in Belgium. Professional software development since 2006. Business application design, systems integration and work on existing systems that are difficult to maintain. Requirements and constraints analysis, development, testing and delivery support. Experience in technical leadership, mentoring and managing a distributed team. ## Skills - **Backend and architecture:** Python, FastAPI, Django, SQLAlchemy, APIs and systems integration. - **Data:** PostgreSQL, SQL, relational modelling, indexing, migration and application transactions. - **Application security:** permissions, ACLs, OAuth 2.0, SAML, code review and OWASP practices. - **Delivery and operations:** Linux, Docker, Docker Compose, Azure Pipelines and GitHub Actions. Experience using Kubernetes in an existing application environment. - **AI-assisted development:** directing work with assistants, reviewing and validating generated code. - **Document AI:** design and validation of a private assistant using local models, vector search and access controls. First IT phase delivered; project in development. - **Frontend:** React, JavaScript, HTML and CSS, complementing a primarily backend practice. - **Java, 2006-2021:** development, architecture and technical leadership, including Spring and Hibernate. ## Professional experience Periods may overlap: some assignments ran alongside main engagements. ### Since 2021: Engie GEMS, Python applications for trading and market access Sole maintainer for the UK and short-term trading scopes of a legacy Python application exceeding 600,000 lines. Designed an application to take over its booking rules across several markets, cleaned and migrated those rules, and implemented cache invalidation for three consuming applications. Implemented user-editable business rules: Excel → YAML → Python engine, with permissions and logging. Built a complete proof of concept for integrating positions with an external provider, validated and selected for industrialisation. Engagement scheduled to end on 31 December 2026. ### Since 2025: SILVA Medical, private document assistant Designed an assistant for the IT knowledge of a healthcare organisation. Local models, document retrieval, access control and supervision of AI-assisted development. First IT phase delivered; project in development. ### 2022: SILVA Medical, intranet and knowledge transfer Built the foundations of a Django intranet, integrated Active Directory and paired with an in-house developer. Supported the in-house developer in taking over further development and maintenance. ### 2020, 2023 and 2024: presentation websites Developed websites for a photographer, a healthcare professional, a tattoo studio and an association. Java/Spring or Python/Django depending on the project, with search engine optimisation follow-up for the Django sites. ### 2018-2021: Mobilosoft, Head of IT Designed and developed a Java/Spring/PostgreSQL platform to replace the existing PHP application. Cleaned and migrated customer data. Managed six developers across Brussels and Madagascar, including technical recruitment, mentoring and code reviews. New platform delivered in mid-2019. ### 2004-2018: development, architecture and integration Some assignments ran in parallel. - **2017-2018 · VOO:** Java systems integration and Docker adoption. - **2017 · SWIFT:** Java development of a data model simulation application. - **2016-2017 · bpost:** Java development. - **December 2015 to late 2016 or early 2017 · Rise + Shine Agency:** Freelance analysis, architecture and Java development. - **December 2015 to August 2016 · Genesis Consult / UCM:** Development of features, complex documents and tests for a social contribution management application replacing a mainframe system. - **September to December 2015 · Genesis Consult / Le Forem:** Freelance Java analysis and development for training and employment applications. - **November 2014 to August 2015 · Genesis Consult / SPF Finances:** Backend and frontend development, service integration and tests for the dematerialisation of bearer securities. - **September to November 2014 · Genesis Consult:** Analysis, architecture and development of an internal resource management tool. - **June to September 2014 · TRASYS / ECHA:** Java OCR pipeline optimisation through parallel page processing and text reconstruction, validated locally. - **June 2012 to May 2014 · Emakina / Samsung:** Backend architecture and development for a European CRM platform, SSO and third-party integrations; technical coordination of seven developers. - **March to May 2013 · Emakina / Deutsche Bank:** Architecture and technical guidance for three developers building a customer welcome portal. - **January to May 2012 · Emakina / FedICT:** Development, maintenance and participation in a web platform migration. - **September to December 2011 · Emakina / BNP Paribas Fortis:** Initial design and partial development of an application monitoring tool. - **March to December 2011 · Emakina / Samsung:** Development and maintenance of an existing CRM platform. - **May 2008 to August 2011 · BF Engineering:** Backend architecture and development of a vehicle tracking platform replacing a WinDev application; GPS communications and trajectory reconstruction from inconsistent positions. - **May 2008 to August 2011 · percil.be:** Consulting, Java tools and websites as a secondary activity. - **May 2007 to April 2008 · Steria / European Commission:** Adapted a load simulation tool and developed a data quality analyser to prepare a migration. - **April 2006 to April 2007 · Unisys / SPF Justice:** Junior Java development for a judicial case management application. - **August 2004 to March 2006 · SmalS-MvM / SPF Justice:** First-line IT support. - **July 2004 · Perceval Technologies:** PHP development internship for Cisco router configuration. ## Education and languages - Computer science studies at Institut Paul Lambin, 2000-2002. - Training in network administration, web components, J2EE development and Adobe CQ5, between 2003 and 2013. - French: native language. - English: very good spoken and written proficiency. ## Knowledge transfer and training Designed and delivered training for IT professionals on understanding AI and its uses in IT, then integrating generative AI into software development activities. Mentoring, pair programming and code reviews. ## Contact Olivier Perceval Percil Solutions SRL, Belgium [olivier@percil.solutions](mailto:olivier@percil.solutions) [+32 484 46 22 91](tel:+32484462291)