[DevoxxFR2012] The Five Mercenaries of DevOps: Orchestrating Continuous Deployment with a Multidisciplinary Team
Lecturer
Henri Gomez is Senior Director of IT Operations at eXo, with over 20 years in software, from financial trading to architecture. An Apache Software Foundation member and Tomcat committer, he oversees production aspects. Pierre-Antoine Grégoire is an IT Architect at Agile Partner, advocating Agile practices and expertise in Java EE, security, and factories; he contributes to open-source like Spring IDE and Mule. Gildas Cuisinier, a Luxembourg-based consultant, leads Developpez.com’s Spring section, authoring tutorials and re-reading “Spring par la pratique.” Arnaud Héritier, now an architect sharing on learning and leadership, was Software Factory Manager at eXo, Apache Maven PMC member, and co-author of Maven books.
Abstract
This article dissects Henri Gomez, Pierre-Antoine Grégoire, Gildas Cuisinier, and Arnaud Héritier’s account of a DevOps experiment with a five-member team—two Java developers, one QA, one ops, one agile organizer—for continuous deployment of a web Java app to pre-production. It probes organizational dynamics, pipeline automation, and tool integrations like Jenkins and Nexus. Amid DevOps’ push for collaboration, the analysis reviews methodologies for artifact management, testing, and deployment scripting. Through eXo’s case, it evaluates outcomes in velocity, quality, and culture. Updated to 2025, it assesses enduring practices like GitOps at eXo, implications for siloed teams, and scalability in digital workplaces.
Assembling the Team: Multidisciplinary Synergy in Agile Contexts
DevOps thrives on cross-functional squads; the mercenaries exemplify: Developers craft code, QA validates, ops provisions, organizer facilitates. Jeff outlines Scrum with daily standups, retrospectives—roles fluid, e.g., devs pair with ops on scripts.
Challenges: Trust-building—initial resistance to shared repos. Solution: Visibility via dashboards, empowering pull-based access. At eXo, this mirrored portal dev, where 2025’s eXo 7.0 emphasizes collaborative features like integrated CI.
Metrics: Cycle time halved from weeks to days, fostering ownership.
Crafting the Continuous Deployment Pipeline: From Code to Pre-Prod
Pipeline: Git commits trigger Jenkins builds, Maven packages WARs to Nexus. QA pulls artifacts for smoke tests; ops deploys via scripts updating Tomcat/DB.
Key: Non-intrusive—push to repos, users pull. Arnaud details Nexus versioning, preventing overwrites. Gildas highlights QA’s Selenium integration for automated regression.
Code for deployment script:
#!/bin/bash
VERSION=$1
wget http://nexus/repo/war-$VERSION.war
cp war-$VERSION.war /opt/tomcat/webapps/
service tomcat restart
mysql -e "UPDATE schema SET version='$VERSION';"
2025 eXo: Pipeline evolved to Kubernetes with Helm charts, but core pull-model persists for hybrid clouds.
Tooling and Automation: Jenkins, Nexus, and Scripting Harmonics
Jenkins orchestrates: Jobs fetch from Git, build with Maven, archive to Nexus. Plugins enable notifications, approvals.
Nexus as artifact hub: Promoted releases feed deploys. Henri stresses idempotent scripts—if [ ! -f war.war ]; then wget; fi—ensuring safety.
Testing: Unit via JUnit, integration with Arquillian. QA gates: Manual for UAT, auto for basics.
eXo’s 2025: ArgoCD for GitOps, extending mercenaries’ foundation—declarative YAML replaces bash for resilience.
Lessons Learned: Cultural Shifts and Organizational Impacts
Retrospectives revealed: Early bottlenecks in handoffs dissolved via paired programming. Value: Pre-prod always current, with metrics (build success, deploy time).
Scalability: Model replicated across teams, boosting velocity 3x. Challenges: Tool sprawl—mitigated by standards.
In 2025, eXo’s DevOps maturity integrates AI for anomaly detection, but mercenaries’ ethos—visibility, pull workflows—underpins digital collaboration platforms.
Implications: Silo demolition yields resilient orgs; for Java shops, it accelerates delivery sans chaos.
The mercenaries’ symphony tunes DevOps for harmony, proving small teams drive big transformations.