Sylvain Wallez

Education

MS in Computer Science, Université de Technologie de Compiègne (UTC), France, 1989. Special mention in Artificial Intelligence.

Skills

Abilites

• Passionate architect and developer. Great abilities at both analyzing and synthesizing, finding robust creative solutions to complex problems.
  
• Highly knowledgeable in open source dynamics, member of the Apache Software Foundation.
  
• Good communication skills as mentor, trainer and team leader. Speaker at conferences, cofounder of the Toulouse JUG.
  
• Interested in mixing art and technology, member of the Toulouse hackerspace.

Technologies

• Everything Java, from clusters to phones, from high-level distributed archictectures to low-level debug and optimization. Using Scala when possible.
  
• SQL and NoSQL systems: Hadoop, MongoDB, Cassandra, MySQL, JPA and homegrown persistence layers.
• Search engines: used Lucene/Solr/Elasticsearch in many different contexts such as search, dynamic ad serving, music taste matching, etc.
  
• HTTP and all its uses: scalable systems, caching proxies, REST architectures, content negociation, etc.
  
• Intimate knowledge of HTML, CSS, JavaScript and XML.
  
• Devops and system administration, considering operational and monitoring constraints right from the start.

Experience

OVH, since may 2015

• Project lead for the Time Series database as a Service, OVH's first PaaS product
• Designed the system from the ground up, including requirement gathering and product definition
• Responsible for running the system (100+ bare metal servers receiving 3 million datapoints/sec)
• Team leader for the Toulouse office, consisting of 10 engineer team (devs, devops, sys admins and data scientists)

Key technologies:  Go, HBase, Kafka, Mesos, Docker, Spark, Java, Scala, AngularJS

Freelance architect and developer, november 2010 - april 2015

• Actoboard - SaaS metrics dashboards: data collection, aggregation and real time display
• Cofounder, product manager, architect and lead developer
  Key technologies: Scala, MongoDB, Cassandra, Spray, Akka, Hazelcast, AngularJS, Ubuntu
• Sigfox - a global IoT network operator
  
• For 2 years, architected and led the development of the central servers that manage all aspects of the network. Started the development from scratch, hired and led a team of 6 people.
  Key technologies: JEE, Spring, MongoDB, clustering, Hazelcast, Apache, Ubuntu
• TRDR - financial+social news feed
  
• Remote consulting and development for a San Francisco startup. Built the news feed system with Elasticsearch: live indexing of news scraped on the web, news feed generation using highly customized scoring mixing the user's financial and social signals.
  Key technologies: JEE, Spring, Elasticsearch, MongoDB
  
• TEcoutesQuoi - a dating website based on music taste affinity
  
• Cofounder, architected and led the development of the entire system, based on correlating Facebook likes with a music metadata database to compute profile similarity. Being bootstraped, we had some success with several thousand users but failed to find funding and closed the site.
  Key technologies: PlayFramework, Lucene, MongoDB, Hazelcast, jQuery
• Datasio - data science and big data consulting
• Log processing and analytics system. Distribution calculation, anomaly detection, reporting.
  Key technologies: Hadoop, Scalding
• Development of the product catalog search engine for France's #1 ecommerce site (10M+ products). Data modeling, ingestion pipeline, authorization management for 12,000 categories and 7,000 merchants.
  Key technologies: Solr, SQLServer
• VirtualScale - big data and virtualization consulting
• Instructor for the Hortonworks training courses (Hadoop, YARN, Hive, Pig)
• Eurecia - SaaS HR product
• Code audit, performance analysis on production systems, and recommendations (server load divided by 5).
  Key technologies: JEE, MySQL
• Mentoring a team of 10 people to improve code quality and development process.
• Sanofi - pharmaceutics
• Clinical drug studies document management: data modeling for the storage in MongoDB and indexing/classification with Solr.

Goojet, now Scoop.it, april 2008 - october 2010

• Chief Technology officer, april 2008 - october 2010
  
• Overall system architecture and technological choices for a horizontally scalable system.
  
• Developer of critical low-level components.
• Tech lead for a 8 people team.
• Member of the operations team for a 10 servers cluster.
  
• Mobile applications team leader, april 2008 - october 2010
• Developing and driving the development of mobile application on J2ME, iPhone and Android. The J2ME application is a hybrid client/server HTML browser that has been successfully validated on more than 400 handsets.

Joost, march 2006 - march 2008

• Backend systems architect and engineering team leader, march 2006 - march 2008
• Architected and designed the backend systems from the ground up, with strong scalability constraints to handle dozens of millions of users:
• metadata harvester/indexer and search engine based on RDF and Lucene,
• advertising engine based on Lucene, and advertising campaign management system,
• recommendation engine base on collaborative filtering,
• user activity analysis and reporting services using Hadoop.
• Leading a team of 16 developers working in an international environment (US, UK, NL, IT).

Anyware Technologies, 2000 - 2008

Co-founded of the company in 2000, growing it up to 80 employees until it was sold in 2008 for 12 M€ to Wavecom (now Sierra Wireless).

We started as a Java/web/XML technology company for IS projects, and quickly found out it could be the basis of a new kind of products in the industrial automation and machine-to-machine domains.

• Chief Technology Officer
  • Originated the initial ideas and prototypes of many products.
  • Technology watch, analysis and recommendations.
  • Developped the technical foundations of our products.
• Expert consultant and trainer
• Expert consultant for Java, web and XML technologies for customers and internal projects.
• Trainer for Apache Cocoon and XML technologies (about 150 people trained).
• Teamed up with sales people to set up the marketing material and during pre-sales meetings with prospects.
• Product initiator and architect. Among others:
  
  • thinHMI: a web-based monitoring and control application for PLCs and factory automation devices. Connects to the devices to animate process state in real time using AJAX, SVG and Flash.
  • M2M dev suite: an embedded webservice server that runs in the PLCs rather than on a separate server, on J2ME virtual machines. Uses a homegrown 70kB servlet engine and bytecode shrinker.
• Project development

  Involved in many web application projects related to information systems and content management, requiring aggregating data from multiple sources, complex user interaction, and multi-format publishing. Among others:

  • Meta search engine: translation of user requests into queries for SQL and Lotus Notes databases, indexed filesystems, e-mail repositories, etc. Parallel query execution and clustered presentation of aggregated results in HTML and PDF
    
  • CMS: documents are stored as XML in a versioned repository, and converted to/from HTML, OpenOffice and MS Word to allow content editors to choose their preferred way of writing content. After a validation workflow, documents are published in HTML and PDF.

The Apache Software Foundation, since 2001

• Vice President, 2003 - 2006
  • Chair of the Apache Cocoon project. Responsible for the relations between the Foundation's board and the project.
• Member, since 2002
  
  • Mentor for several new Apache projects: Pig, a data analysis language, Wicket, a component-oriented web application framework, Felix, implementation of the OSGi specification, Jackrabbit, reference implementation of the Java Content Repository API, Shindig, an OpenSocial container.
    
  • Member of the Java Community Process expert group for JSR-283 (JCR version 2).
  • Interviewed by several French IT magazines about Apache.
• Committer, since 2001

  Core developer of the Cocoon project, a Java web application framework using XML transformation pipelines to produce a large range of output formats.

  Noticeable contributions, among many others:

  • Main developer of the form handling subsystem, featuring declarative definition of complex forms and field validation, with Ajax support for immediate user feedback.
  • Maintainer of the Flowscript engine, a web application controller using continuations in JavaScript. Good knowledge of the internals of the Rhino interpreter.
  • Wrote interpreters for a number of XML-based languages, including Cocoon's pipeline assembly language.
    

Alcatel Space Industries (now Thales), 1990 - 2000

• Architect, R&D team manager, 1997 - 2000
  • Lead architect of a number of reusable components for satellite control systems, managed a team of 6 people.
  • Developed a transparent object persistence system for distributed applications in Java: byte-code instrumentation to detect object state change, distributed transactional cache using RMI or CORBA, and delegation of database operations to DAOs (that pattern wasn't named at that time).
• Intranet Webmaster, 1995 - 2000
  • Set up the very first HTTP server in the company to promote knowledge sharing.
  • Wrote a web-based issue tracking system using an early version of Zope (Python).
• Software developer and project manager, 1990 - 1997
• Ground station monitoring and control system (5 people, Japanese customer): architecture, development of a fail-safe network communication library in C++ for a redundant network.
• Satellite mission planning system simulator (4 people): architected the project, and wrote the simulation engine (in Ada), for a GUI written using X11/Motif.
• Wrote a code generator in Prolog to allow fast design/code roundtrips using the HOOD design method.