Back-End Engineer [Freelance]

Paris hybrid Until 8/21/2026 First posted May 1, 2026 Last posted May 1, 2026
Job description

👫 About the team

At Equativ, we’re on a mission to develop advertising technologies that empower our customers to reach their digital business goals. This means that we rely on massively scalable, widely distributed, highly available, and efficient software systems; the platform deals with over 3 million requests per second (+250 billion/day) managed by 3,000 servers with less than 250ms response time.

Our innovation team based in Paris, Nantes, Bordeaux, Limoges, Krakow and Berlin is composed of 150+ straightforward and energetic engineers working in an Agile environment and ready to tackle the most complex technical challenges.

✏️ Your mission

You will join our Addressability team distributed in multiple locations. You will be onboarded in a multi expertise feature team of back-end developers and Data Engineers, with the mission to build and query a multi billion entry Id Graph, plug third party data providers and provide customers and business teams with advanced targeting and reporting features.

What you'll do ✏️

  • Ingestion of massive amounts of data high performance key value stores

  • Query user data millions of times per second with a response time of a few ms

  • Improvement of our graph by making it sharper, faster

  • Design trade offs (feature vs performance) 

  • Business support on external partners' and customers 

💪 About you

  • 3-4 years of seniority in high perf, low latency C# coding

  • Expertise of Aerospike or equivalent high performance KV store 

  • Experience with Event streaming (Kafka), Go, PHP, Docker, Kubernetes, Cloud platforms (ideally GCP) is a big plus

  • Able to lead design discussions and mentor others

  • Customer oriented approach: you deliver clean and usable solutions for customers (and you know that customers hate bugs!)

  • Proficient in verbal and written English

  • Passion for writing high quality and maintainable code following Software Craftsmanship or Continuous Delivery

  • Entrepreneurial spirit and know-how to identify opportunities of improvement

  • Personal projects with code sharing, we’re curious about your art!

About this role

Summary

Develop high-performance, low latency backend systems and enhance data querying capabilities.

Job title

Back-End Engineer [Freelance]

Experience level

3-4 years

Industry

software

Location requirements

Based in Paris, remote work not specified.

Salary

Not specified

Management role

No

Skills & keywords

Required skills

C#Aerospikehigh performance KV storeKafkaDockerKubernetesEnglish

Preferred skills

GoPHPGCPcloud platforms

Specializations

high perflow latencydistributed systemsdata ingestionbackend development
Locations

Structured locations inferred from the posting.

Paris, France

Hybrid City