Julien MAILLERET

Senior Site Reliability Engineer (Engineering Productivity / Release Engineering / Platform Engineering)

Nantes, France (Remote)

contact@mailleret.fr • https://julien.mailleret.fr • https://github.com/jmlrt • https://www.linkedin.com/in/julienmailleret

Summary

Senior SRE in Engineering Productivity / Release Engineering, designing and building internal developer platforms and tooling in Go and Python. Contribute to technical standards and best practices across Engineering Productivity teams through documentation and knowledge sharing. Experienced in large-scale build/release systems (500+ artifacts, 15+ repositories), Kubernetes/GitOps orchestration, API and infrastructure integrations, and supply chain security (code signing, artifact publishing).

Focus: internal tooling and platforms, release engineering, CI/CD platforms, Kubernetes/GitOps automation, supply chain security.

Core Skills

• Languages: Go, Python, Bash
• Release Engineering: build/release automation, artifact management, CI/CD platform design
• CI/CD & GitOps: Buildkite, GitHub Actions, Jenkins, Tekton, Argo CD, Argo Workflows
• Kubernetes: custom controllers/CRDs, Helm
• Cloud & Infrastructure: AWS, GCP, Terraform, Ansible, Pulumi
• Security: code signing (GPG, Windows, macOS, container images), HashiCorp Vault, supply chain security
• Systems & Operations: Linux, incident response, troubleshooting, on-call
• Leadership & Collaboration: technical leadership, mentoring, cross-team coordination, technical documentation
• AI-augmented Development: Cursor, GitHub Copilot, Claude Code

Experience

Elastic — Senior Site Reliability Engineer (2019-Present) — Remote (France)

• Design and build release automation, internal developer tooling in Go and Python for Elastic’s build and release infrastructure.
• Automate and operate build and release infrastructure for 500+ artifacts across 15+ repositories; ship 30-60 versions/year.
• Operate Kubernetes-based GitOps deployment orchestration across multiple cloud providers and environments.
• Manage and improve code signing for stack artifacts and build tooling to integrate with external systems (Red Hat Partner Registry, IronBank).
• Author technical standards, design documents for release infrastructure; establish patterns adopted across Engineering Productivity.
• Coordinate cross-team delivery for new artifact releases; participate in follow-the-sun on-call; lead incident response, RCAs.
• Mentor junior engineers and onboard new team members.

Selected impact:

• Built Kubernetes controller in Go (custom CRD + reconciliation loop) with Argo Workflows; enabled 11 teams to migrate 57 services to self-service deployments across 6 environments.
• Led migration of build/release pipelines from Jenkins/Tekton to Buildkite; designed pipeline generator (Go + custom DSL) for 13 pipelines, 16 teams; reduced 20,000+ lines of YAML, improved performance 50%.
• Reduced stack build time from 8+ hours to 2.5 hours via parallel builds (ephemeral CI workers) and asynchronous processing; enabled operating up to 4 releases in parallel.
• Owner of an internal initiative for coordinating pre-release validation across 10+ teams, enabling early testing of release build candidates.
• Maintained Elastic public Helm charts and Ansible roles as community maintainer; drove roadmap, triaged issues, reviewed community PRs, transitioned Helm charts from beta to GA before deprecation.

Talend — Site Reliability Engineer (2017-2019) — Nantes, France

Managed Talend Cloud infrastructure; automated stack builds/deployments with multi-tenant, multi-region patterns. Built Kubernetes platform with Kubespray, Ansible, Terraform, AWS EKS; integrated Data Stewardship and Data Catalog.

Weekendesk — Lead DevOps (2015-2017) — Paris, France

Led production team; automated build/deployment; defined change/incident/on-call processes; set up 24/7 on-call. Migrated infrastructure from on-premises to AWS; improved for TV campaign traffic spikes (autoscaling, CDN, load-testing).

AXA — System/Middleware Engineer (2004-2015) — Paris, France

Managed Unix servers (200+ Linux/AIX), middleware applications, and SAN systems; contributed to 24/7 on-call support. System administration apprenticeship while completing Master’s degree (2004-2008).

Education

Master’s degree, Information System Management — ITIN-ESCIA (2003-2008) — Paris/Cergy, France