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Siren

Senior Java Developer - Big Data

Siren
France · Full-time · Mid-Senior

Senior Java Developer - Big Data


Are you an experienced professional with a passion for technology and problem-solving? Do you thrive on translating complex requirements into successful solutions and enjoy working directly with customers to ensure smooth adoption?


We are looking for:

We are looking for a very passionate expert in Java and Distributed Systems that will be part of our back-end team. Our back-end team is responsible in designing and developing the Siren Federate product. Siren Federate is a distributed query processing and federation layer built on top of Elasticsearch and designed for interactive analytics over different types of data sources. 


At Siren, we’re driven by our mission to keep people, assets, and networks safe. We partner with organisations around the world tasked with protecting communities — and your expertise will help make that possible.


📍 Apply now and help shape technology that safeguards the world.


We offer: 

  • An engaging role in a leading software company impacting critical use cases in diverse sectors like Law Enforcement, Cybersecurity, Finance, and Pharma.
  • A chance to work with a world-class team possessing deep expertise in Search, Information Retrieval, Knowledge Graphs, and Analytics.
  • Opportunities to work with cutting-edge AI technologies to drive smarter solutions and innovation.
  • A collaborative and dynamic environment fostering mentorship and continuous professional growth.
  • Flexible work and remote-friendly work arrangements, embracing our core values of Innovation, Speed, Customer Empathy, Trust, and Ethical Technology.


Team culture

We are building a strong, diverse team of curious, creative people who want to do purposeful and thoughtful work and support each other in the process.


Our core values shape the culture of the whole team and how we do business.

  • Innovation: We value innovation and creativity in delivering on our vision
  • Speed: We value fast decision-making while being thoughtful
  • Customer empathy: We are empathetic and responsive to our users and their everyday challenges
  • Trust: We trust each other to get the job done while supporting each other
  • Ethical technology: We show dedication to unbiased technology with a conscience and commitment to technology transparency


Your roles and responsibilities will consist in:

  • Be a leader in the design and development of the APIs, product features and add-on components.
  • Collaborate and coordinate with members of the development team, creating high quality implementations, and review of the work of others.
  • Work as part of an agile team and also working directly with the founders of the company and the senior team.


We expect:

  • MS degree (or equivalent) in Computer Science, Engineering or a related subject
  • At least 5–8 years of experience in Java development.
  • Hands-on experience with Java asynchronous, distributed, and multi-threaded systems.
  • Experience designing, building, and maintaining production-quality software systems.
  • Ability to work effectively in a collaborative, distributed engineering environment.
  • Strong problem-solving skills and a willingness to learn and grow.
  • Solid understanding of software development best practices, including code quality, testing, and reviews.
  • Experience applying data structures and algorithms to build efficient systems, with attention to performance and optimisation.
  • Prior experience with Elasticsearch, Solr, Lucene or any experience in Information Retrieval is not required, but it is a plus.


Why You Should Join Siren

Join Siren for a unique opportunity to contribute to a cutting-edge product, backed by leading Irish VCs. Experience a fast-paced, startup culture where you can significantly influence your role and grow professionally in a dynamic environment, with a great work like balance and lots of fun.


Equal Opportunities Employer

Siren is an equal opportunity employer dedicated to diversity and inclusivity. We do not discriminate based on race, religion, colour, national origin, gender, sexual orientation, age, marital status, or disability status.


Recruitment Agencies

We have a preferred supplier list of trusted partners to assist us when required, and do not acknowledge any speculative CVs or unsolicited candidate introductions from agencies not on this list.

Key Skills

Ranked by relevance

java elasticsearch data structures cybersecurity responsive ai
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Posted
Jan 24, 2026
Type
Full-time
Level
Mid-Senior
Location
Talence
Company
Siren

Industries

Technology Information Internet

Categories

Engineering Information Technology

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