Walid Karray
Freelance Hands-On Solutions Architect · AWS · GenAI
[email protected]
Paris, France · Remote-friendly
linkedin.com/in/karray
github.com/tux86
medium.com/@walid.karray
Summary
Hands-on solutions architect with a product mindset: I design architectures and build them, from idea to production, and I measure them by the user outcomes and business value they deliver. In 16+ years I've done it on both sides of the table: consulting for Fortune 500s, and as co-founder CTO scaling a startup to 1M+ users (official ticketing provider for AFCON 2023). Today I ship Generative AI that runs real business processes (multi-agent systems, RAG and LLM orchestration in production at enterprise scale), on deep foundations in AWS serverless, event-driven architecture and IaC. AWS Certified Solutions Architect. Open to freelance missions.
Core skills
- Cloud & AWS
- Serverless, Lambda, API Gateway, EventBridge, SQS, AppSync / GraphQL, Cognito, Aurora PostgreSQL, event-driven architecture
- Generative AI
- AWS Bedrock, multi-agent orchestration, RAG, LLM orchestration, OpenRouter, Text-to-SQL, AWS Textract, vector search (MongoDB Atlas)
- Languages & runtimes
- TypeScript, Node.js, Bun, Python
- IaC & DevOps
- Terraform, CI/CD (GitHub Actions), Docker, LXC, Proxmox VE / PBS, security scanning (Checkmarx, Semgrep)
Experience
TotalEnergies
Hands-On Solutions Architect
- DAIA: GenAI pipeline (GPT models via the group's internal LLM platform, integrated with SAP Datasphere) that checks every purchase request against procurement policy and approves the compliant ones automatically, removing manual review and unlocking ~€2M/year in savings.
- Synaps: enterprise GenAI assistant with multi-agent orchestration, featuring an autonomous agent driving SAP with zero manual intervention and natural-language querying across 5 databases via RAG.
- Both products run on the multi-tenant serverless platform I architected (Lambda, API Gateway, EventBridge, SQS): TypeScript backend, Python execution engine, a catalog of 50+ step handlers reused org-wide.
- Built the CI/CD pipeline for the SAP Fiori/UI5 applications: automated build and deployment, integrated with ServiceNow change management.
- E2E test suite covering multi-tenancy, RBAC and resource sharing; CI/CD (GitHub Actions) with blocking security scans (Checkmarx, Semgrep).
SNCF Connect & Tech
Cloud Engineer · AWS Serverless
- Contributed to the development of the next-gen audio-visual broadcasting system for train stations, on real-time AWS serverless: rolled out to every SNCF station with zero downtime, reaching 21M+ travelers nationwide.
- Designed the testing strategy (unit, integration, automated, load) and the acceptance criteria enforced with the QA team, the groundwork behind the zero-downtime rollout.
Maxeon Solar Technologies
AWS Solutions Architect
- Architecture mission for a global solar-panel manufacturer: serverless-first AWS migration of the platform serving 5 international markets, cutting infrastructure costs and unlocking scale.
- Unified Okta SSO, Salesforce CRM, AlphaESS and Net2Grid IoT energy data into a single platform, with seamless data flows across systems.
Ticketchainer
CTO & Co-Founder
startup
- White-label B2B2C sports-ticketing SaaS, built from scratch as co-founder CTO with a Lean Startup approach: 1M+ users and 10M+ tickets sold in three years.
- Architected the serverless AWS stack, designed to auto-scale across client organisations.
- Official ticketing provider for AFCON 2023: the platform held 350K daily peak connections and 25K tickets sold per day.
- Raised seed funding, grew the engineering team from 2 to 20, and reached 40+ client organisations (Betclic Group, AC Ajaccio, CAF).
France Médias Monde
Full-Stack Developer & Technical Referent
- Contributed to the development of the editorial SaaS CMS adopted by 4 international newsrooms (France 24, RFI, MCD, Observers) publishing in 22 languages.
- Backend development of InfoMigrants (FMM × Deutsche Welle × ANSA, EU co-financed): verified news for migrants in 6 languages, mobile-first, read by millions.
France Télévisions
Full-Stack Developer
- Delivered the REST API and microservices backbone for the digital platforms, with PoCs (SonarQube, MongoDB) that set the move to a microservices architecture.
RATP Smart Systems
Full-Stack Developer
- Built the backend API of "Visitez Paris en métro", RATP's public guide to exploring Paris by metro.
- Built Python pipelines extracting and transforming the rail network's logs into statistical datasets published for the general public.
Hub-Scan Inc
Backend Developer (PHP)
- Built the backend and REST APIs (CodeIgniter framework), and wrote the technical documentation, for the redevelopment of Hub'Scan, a SaaS platform that audits and validates digital analytics and marketing tags at scale.
Tritux Group
Full-Stack Developer
- Built enterprise web applications (Java JEE, PHP) for public-sector, telecom and banking clients, at an official RedHat partner.
Education
BTS · Networking of IT & Telecom Systems ISET Djerba · 2006 – 2010
Certifications
AWS Certified Solutions Architect – Associate 2023
OCJP 6 · Oracle Certified Java Programmer 2011
Languages
French Native / Bilingual
English Fluent · daily working language
Arabic Native / Bilingual