Freelancer profile translated to English.
Back to original languageAbout William
Fast intervention on Linux server incidents. Available and responsive, I intervene within 1 hour on critical situations: server down, network security breach, performance degradation.
Systems and network administrator for over 20 years, I make your Linux servers faster, more stable, and more secure – whether it's a dedicated server, VPS, web hosting, or business application.
96 missions completed on Malt with a 5/5 rating.
🌐Web Hosting & Websites
- Slow or inaccessible site: diagnosis, Apache/Nginx optimization, caching
- WordPress, CMS, e-commerce web hosting: optimized LAMP/LEMP stack, server updates
- System administration panels: Plesk, ISPConfig — installation, migration, troubleshooting
- Hosting provider migration: transfer, DNS, SSL
🖥️Servers & Infrastructure
- Dedicated & VPS Linux Server: installation, hardening, Debian/Ubuntu optimization
- Virtualization: Proxmox VE, high-availability clusters, VMware migration
- Network: VLANs, load balancing, HAProxy reverse proxy, high-availability architecture
- Automation: Ansible, Docker, Bash scripts
🗄️Databases
- MySQL / MariaDB: performance tuning, slow queries, memory optimization
- Replication, automated backup, disaster recovery plans (DRP)
- Storage: ZFS, RAID, encrypted backup solutions
🔒Network Security & Protection
- PfSense firewall, VPN (OpenVPN/WireGuard), system hardening, fail2ban
- Security audit, vulnerability patching, compliance
- Monitoring: Grafana, real-time alerting
🛡️IT Management & Systems/Network Administration Support
- Proactive maintenance: 24/7 monitoring, updates, anticipating failures
- Responsive technical support and clear documentation
- Long-term support for SMEs and startups
Need urgent intervention or long-term system administration support? Contact me, I respond within 1 hour.
French
Native or bilingual
English
Fluent
Can work on-site
Paris (up to 50km), Lyon (up to 50km), Bordeaux (up to 50km), Marseille (up to 50km), Lille (up to 50km)
Experience
- Voxa.centerInstallation of VoIP Telephony Service, WEBRTCE-COMMERCEApril 2026 - April 2026Paris 15 Vaugirard, FranceI designed, developed, and deployed Voxa Center, an open-source VoIP telephony platform powered by Asterisk 20. This project leverages my skills in Linux server administration, network administration, telecom protocols (SIP/RTP), infrastructure security, and DevOps automation.Linux Server AdministrationI deployed the infrastructure on Debian 12 / Ubuntu Server in native installation: compiling Asterisk 20 from source, orchestrating all services via Systemd (Asterisk, PHP-FPM, Nginx, MariaDB, Redis), server hardening with Fail2ban, iptables/nftables, SRTP/TLS encryption, and Let's Encrypt certificates. Performance tuning: PHP-FPM, MariaDB (InnoDB), Redis. Centralized log management with journald and logrotate.Network & Telecom AdministrationI configured a production SIP/SRTP architecture with multi-operator interconnection (OVH, Twilio, Vonage): SIP trunks, G.711/G.722/Opus codecs, call routing. Deployed a WebRTC softphone with Nginx WebSocket proxy, ICE/STUN NAT traversal, and DTLS-SRTP. Developed an application-level SIP firewall with dynamic IP filtering, rate limiting, and Fail2ban synchronization. Mastery of TCP/UDP flows, SIP/RTP ports, DNS, and voice QoS.DevOps & AutomationI wrote an automated bash installer (curl | bash) that provisions a bare-metal server in 5 minutes: compilation, configuration, SSL certificates, and systemd services. Fully reproducible and version-controlled infrastructure on GitHub. Integrated monitoring dashboard with live supervision, CDR logs, and statistics. Embedded update mechanism with database migration and rollback.
- Orbiter.systems🚀 Optimization of web infrastructure and TTFB reduction in shared hosting environmentTECHFebruary 2026 - April 2026 (2 months)Paris, FranceA client hosting several websites (WordPress, PrestaShop) on a shared hosting infrastructure was experiencing critical issues: high TTFB (> 800 ms) impacting SEO and user experience, performance degradation under load, lack of isolation between sites ("noisy neighbor" effect), and complex maintenance due to a single PHP stack.As a systems and network administrator, the goal was to stabilize the infrastructure while significantly improving performance.The solution involved deployingOrbiterto containerize each website, isolate PHP-FPM processes, and allocate dedicated resources (CPU, RAM). Concurrently, server and network optimization was implemented: Nginx HTTP caching, optimized reverse proxy configuration, reduction of backend calls, and PHP performance tuning.The environment was administered under Linux Debian in production, with multi-version PHP management (7.4 to 8.x), resource monitoring (CPU, RAM, I/O), and system parameter adjustments (workers, buffers, ulimit).The results obtained are significant: TTFB reduction from ~800 ms to 120–180 ms (up to -80%), improvement in loading times by 40% to 60%, capacity to handle +70% simultaneous traffic without degradation, complete site isolation (no cross-incidents), and a 30% reduction in technical intervention time.This project led to direct improvements in SEO (Core Web Vitals), provided a better user experience, and made the infrastructure more resilient and scalable, while reducing operational costs.It exemplifies a comprehensive systems and network administration intervention, combining system optimization, network performance, and infrastructure modernization with concrete and measurable results.
- eConnectFrAWS Infrastructure IT Management — Automation and MonitoringTECHJanuary 2026 - Today (7 months)Lille, FranceComplete IT management of an AWS cloud infrastructure with over 20 instances. Implementation of custom automation, containerized backup solutions, and real-time monitoring.🖥️ AWS InfrastructureAdministration of 20+ production EC2 instancesS3 storage management: retention policies, lifecycle rules, encryptionRDS database administration: maintenance, tuning, replicationIAM rights management, security groups, and VPC network architecture⚙️ Bash & Python AutomationDevelopment of Bash scripts for recurring tasks: log rotation, cleanup, health checksDevelopment of Python scripts for orchestration: provisioning, EC2 snapshot management, S3 synchronizationScheduling and orchestration via cron and systemd timersDocumentation and versioning of all scripts🐳 Containerized Backup with DockerDesign of an automated containerized backup solutionDedicated Docker containers: RDS database backup, EC2 snapshots, S3 exportBackup orchestration with dependency management and retry on failureAutomatic backup integrity verification📊 Grafana + Prometheus MonitoringDeployment of a containerized Prometheus + Grafana stackExporters on each EC2 instance: CPU, RAM, disk, network metricsCustom dashboards per service: EC2, RDS, S3, backupsReal-time alerting: Slack/email for anomalies or backup failures✅ Results:20+ instances supervised in real-time. 100% automated and daily verified backups. Incident detection time reduced thanks to Prometheus alerts. Several hours saved per week on recurring administration tasks.Technologies: AWS (EC2, S3, RDS, IAM, VPC), Linux, Bash, Python, Docker, Prometheus, Grafana, automation, backup, monitoring
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Education
- Technical BaccalaureateAlbert de Mum1995