PRE-HIRE - Techlead Frontend / Software Architect (Microfrontend specialist) - Freelance (M/F)

Mission Context

PRE-HIRE - 6-MONTH MISSION

Within the Digital Experience team, you will be the architect of the "Shell": the technical cornerstone that unifies our legal products, our massive search tools, and our generative AI services. Your mission is not to build a simple application, but to design the Runtime Orchestrator capable of making Micro-Frontends (Workspaces) developed by independent teams across Europe coexist. You will guarantee a "Seamless" user experience (zero reloading) while managing high-level technical complexity (high-performance viewers, AI streaming, context isolation).

Objectives and Deliverables

1. Shell & MFE Architecture Design

• Runtime Design: define the dynamic module loading strategy, shared cache management, and context isolation.
• Technological Arbitration: challenge the target stack. We have a strong preference for a Module Federation 2.0/Rspack ecosystem, but you will be responsible for confirming these choices via PoCs and comparative analyses.
• SSR Strategy: define how to reconcile Micro-Frontends with performance/SEO challenges for our public content.

1. Standardization & Contracts (DX)

• Internal SDK Definition: create communication standards: event bus, unified authentication, and country context propagation.
• Performance & Shared Libs: orchestrate the management of shared dependencies (React as singleton) and cache/CDN strategies to optimize critical loading time.
• Observability & Security: natively integrate telemetry primitives and security guardrails (CSP, Zero Trust, token isolation) at the heart of the runtime.

1. Technical Leadership & Governance

• Inner Source Governance: be an influential member of the Design System Guild to ensure the visual and technical consistency of shared components.
• Value stream teams Support: help squads (AI, Search, Docs.) integrate their products into the Shell with minimum friction. Participate in setting up the DX (Developer Experience) ecosystem.
• Guarantee software excellence through a Craftmanship approach.
• Tech Pioneer: ensure constant monitoring of the ecosystem and contribute to the group's technical influence (articles, meetups, open-source).

Required Skills:

Target Stack:

• Library: React (group standard)
• Languages: TypeScript (mastery required), Node.js
• Orchestration: Module Federation 2.0 (planned Rspack / Rsbuild).
• Ecosystem: TanStack (Router, Query, Start), Zod, Zustand.
• UI: Tailwind CSS, Shadcn/UI, Storybook.
• Tests: Vitest, Playwright.

Expected Skills:

• Proven experience in frontend on large-scale distributed architectures (MFE).
• Bundling Expertise: You master Webpack 5 or Vite and have a deep curiosity for Rust-based bundlers (Rspack, Esbuild).
• Engineering Culture: You know what an interface contract is, you master shared dependency versioning issues and Auth token lifecycles.
• Ability to integrate asynchronous flows (LLM response streaming, WebSockets) within a distributed architecture.
• Fluent English (daily European context).

Soft Skills

• Product Vision: understand the business stakes of law to prioritize Shell features. The shell is managed as a product; you consider other developers as your clients.
• Technical Leadership & Pedagogy: ability to evangelize MFE best practices to other developers.
• Obsession with Quality: absolute rigor regarding data security (Legaltech requirement) and accessibility.
• Innovative Spirit: curiosity for the