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Arthur GallouinAG

Arthur Gallouin

Staff Engineer / Team Lead, Data & Integrations

€850/day
Paris, FR
8-15 years

Average response time: 1 hour

About Arthur

Staff Engineer — Distributed Systems & Data Platforms

12 years of experience building and scaling high-throughput systems, from early-stage startups to multi-tenant SaaS platforms.
Co-founded and built a high-frequency trading platform executing €100M+ in automated volume. Later led data & integrations architecture processing 100M+ rows/day, reducing full-import duration from 2h17 to 14 minutes.
I engage on hard problems: pipeline reliability, architectural redesign, performance at scale, and engineering standards. Comfortable leading technically without losing touch with the code.
Available for 3 to 6-month engagements.
  • French

    Native or bilingual

  • English

    Fluent

Can work on-site
Paris (up to 15km)

Experience

  • Qobra
    Staff Engineer / Team Lead, Data & Integrations
    SOFTWARE PUBLISHING
    November 2024 - Today (1 year and 7 months)
    Métropole du Grand Paris, France
    Lead engineer for Qobra’s data ingestion platform, processing 100M+ rows/day across 6+ heterogeneous sources (CRMs, data warehouses, flat files, public API). Responsible for performance, reliability and architectural direction of all ingestion flows.

    • Reduced full-import duration from 2h17 → 14 minutes by redesigning reference propagation, batching logic, and thread-pool isolation (eliminating cross-tenant blocking).
    • Improved ingestion reliability with nightly full resyncs, reference-consistency scanners and regression tests, reducing customer-visible reference issues from 3/week → ~1/month.
    • Stabilized differential syncs by addressing computed-field drift caused by unreliable update timestamps in upstream CRMs.
    • Built tooling and dedicated test environments for developers & Customer Success, increasing debugging speed and autonomy.
    • Introduced the Shape-Up methodology (6-week cycles), strengthening prioritization, delivery consistency and cross-team alignment.
    • Ensured schema consistency and correctness for the Public API, consumed by multiple engineering teams.
    Python Typescript MongoDB REST APIs Architecture distribuée
  • Front
    Senior Software Engineer, Analytics / Data
    SOFTWARE PUBLISHING
    February 2024 - October 2024 (8 months)
    Métropole du Grand Paris, France
    Built analytics features turning conversations/tickets into actionable metrics (SLA compliance, response times, workload distribution) and improved the foundation of the Insights data model.

    • Led the migration from heuristic “conversation stages” to an explicit ticket-resolution workflow, improving data correctness and simplifying downstream analytics.
    • Designed a full local Elasticsearch environment with synthetic dataset generators, drastically improving developer experience and feedback loops.
    • Reintroduced regression tests for analytics metrics, clarified metric specifications and corrected long-standing inconsistencies.
    • Delivered full-stack contributions across backend Elasticsearch/Painless pipelines and frontend dashboard components.
    Typescript Elasticsearch React.js Testing Node.js
  • Skillup
    Technical Lead
    SOFTWARE PUBLISHING
    March 2021 - January 2024 (2 years and 10 months)
    Métropole du Grand Paris, France
    Scaled the engineering team from 3 → 15 developers; defined team topology, recruited engineers, and established architectural and coding standards.

    • Led the migration to a CQRS + event-sourcing architecture (Kafka + Postgres), improving scalability, decoupling and long-term maintainability.
    • Reduced lead time to production by 50% through CI/CD standardization, improved review workflows and a unified design system (200+ UI components → 60).
    • Introduced clean architecture and domain-driven boundaries enabling autonomous cross-functional feature teams.
    • Acted as technical owner across squads, ensuring product/engineering alignment for Skillup’s HRIS SaaS platform.
    Typescript React.js Neo4j Apache Kafka Node.js

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Education

  • Master of Engineering
    EFREI Paris
    2012
    Master of Engineering

Skill set

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