Backend Python / APIs / ReactJS Engineer - Volumetrics & Real Time - Freelance (M/F)

France | Oct. 3, 2026

Country: France

Type: Onsite

Employment: Full-time

Description: Daily rate (TJM): Budget: TJ: up to €500 excluding VAT/day / permanent contract: €45 - €55 thousand (depending on profile)

BACKEND ENGINEER PYTHON / APIS / REACTJS - VOLUMETRY & REAL TIME (CDI OR FREELANCE)

PRACTICAL INFORMATION

Department: Paris (75). XP

Open position: 1

Sector: Industry

CONTEXT

In a context of digital transformation, a major player in the industry is evolving its solutions, its real-time services and its APIs.

The current environment is partly based on an existing legacy PHP / Drupal, with a strong overlap between business bricks, data flows and web interfaces.

The objective is to evolve this existing towards a more modular, scalable and API-oriented architecture, with a strong focus on building blocks with high business value: flow processing, ingestion and exposure of data.

A key issue of the mission also concerns a data aggregation tool facing significant issues of performance, volume, costs and scaling up, in a context of high traffic and progressive modernization of the IS.

MAIN MISSIONS

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   Resume and understand an existing complex business in a legacy environment

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   Design and develop efficient backend APIs in Python

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   Participate in the redistribution of services and the evolution of the application architecture

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   Work on issues of performance, scalability, volume and costs

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   Contribute to the improvement of the data ingestion, transformation and exposure chains

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   Participate in the progressive modernization of a historically coupled environment

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   Intervene, depending on the scope, on the front restitution in ReactJS

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   Collaborate closely with the product and technical teams in agile operation

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  Participate in technical choices, good development practices and the structuring of solutions

TECHNICAL ENVIRONMENT

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   Python

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   ReactJS

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   JavaScript / TypeScript

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   AWS

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   REST APIs

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   Distributed architectures / microservices

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   Node.js (depending on scope)

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   PHP / Drupal (legacy)

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   Agile / Product methodologies

PROFILE WANTED

We are looking for a profile with proven experience in Python backend development, capable of working on APIs in production in high-demand environments.

The candidate must be comfortable on topics of REST API design, performance, scalability and technical structuring, with a real ability to understand a complex existing situation and support its transformation.

Solid experience on issues involving large volumes of data is expected, particularly on the following subjects: ingestion, transfer, processing and restitution / high-performance display on a large scale. This dimension is central to the mission, in particular on the issues linked to flow aggregation.

The desired profile must also have a good command of an AWS cloud environment, as well as concrete experience on distributed architectures or microservices.

A front sensitivity is appreciated, with an ability to intervene on the ReactJS part according to the needs of the scope.

Beyond the technical stack, we are mainly looking for a person:

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   able to take a step back from a complex existing situation

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   able to propose solutions adapted to business and technical challenges

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   comfortable in transforming environments

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   with a real logic of quality of service, performance and product impact

Apply here:

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