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3E

Clojure Developer

Become a Clojure Developer at 3E in Brussels, Belgium, focusing on back-end systems for renewable energy. Collaborate with a multidisciplinary team to optimize performance and develop scalable solutions. Enjoy flexible working hours and the option for remote work in a diverse, international environment.
3E
3E
Brussels, Belgium   Flexible   Full Time  UTC+01:00

3E

Company Overview

3E (3E NV)

Brussels, Belgium

1999

Approximately 100-150 employees (source: devex.com). No public revenue figures available for 2023 or later.

What They Do

3E focuses on solar energy, wind energy, battery energy storage systems (BESS), sustainable buildings, sites, energy infrastructure, and energy markets. The company offers SaaS platforms and consulting services throughout the entire lifecycle of renewable projects, from development to operation (source: devex.com). Their flagship product, SynaptiQ, is a SaaS platform launched in 2010 that optimizes over 20 GW of connected capacity and provides advice on 90 GW of assets in 2023 (source: 3e.eu). This platform offers performance analytics, proactive monitoring, ROI recommendations, and multi-stakeholder reporting, and is designed for PV, wind, and BESS portfolios.

Projects & Track Record

3E has supported renewable projects in over 40-60 countries with a track record of more than 20 years. A notable project includes optimizing an 800 MW wind portfolio for Renovatio in Eastern Romania through customized measurement campaigns (source: 3e.eu). For Opdenergy in Spain, 3E provided regulatory and technical guidance for hybridizing existing installations with BESS and renewable energy (source: 3e.eu). Ongoing efforts include a partnership with RJE for performance management in Spain and collaborations such as digitizing ReNew Power's 4,100 MW wind/solar portfolio in India via SynaptiQ.

Recent Developments

In 2023, 3E achieved milestones of 20 GW of connected capacity in SynaptiQ and 90 GW of advised assets, and opened an office in Spain (source: 3e.eu). A strategic partnership with BayWa r.e. was announced for global monitoring of PV portfolios using SynaptiQ, focusing on operational excellence across 10 GW of assets (source: baywa-re.com). In 2024-2025, 3E collaborated with TGS on integrating Virtual Met Mast technology into Wind AXIOM for improved wind farm planning.

Working at 3E

3E offers positions in engineering (wind/solar/BESS modeling, system engineering), software/data analysis (development of SynaptiQ, AI solutions), consulting (due diligence, feasibility, project management), and more, with a multidisciplinary team of about 100-150 experts (source: 3e.eu). Active recruitment is taking place at the headquarters in Brussels and at key locations such as Barcelona, Paris, and Cape Town, reflecting the expansions in these regions. The culture emphasizes innovation, international collaboration, and long-term customer relationships, as noted by co-founder/CTO Werner Coppye.

Contact


Last updated on 2025-12-27 | Report an issue

Job Description

SynaptiQ is 3E's SaaS product, an independent, evolutionary software suite for asset management of renewable energy portfolios (more information on 3e.eu/synaptiq). SynaptiQ collects near-real time data of more than 20 million devices spread over 10 thousands utility scale and commercial solar and wind sites spread all over the globe.

We develop and operate advanced analytical services to enrich the monitoring data by:

  • satellite imaging data,
  • meteorological modelling,
  • advanced system modelling,
  • machine learning & artificial intelligence.

The platform combines domains related to big data, high-performance processing, IoT protocols and AI and is the product of the interactions between a multidisciplinary team of developers, scientists, renewable energy architects, electrical engineers, and enthusiast sales that implement, operate and commercialize SynaptiQ worldwide.

The added value realized by SynaptiQ is performance improvement and operational cost reduction for its Operations & Maintenance customers.

What you will be doing

We are looking for a Back-End Developer with experience in Clojure and a passion for creating efficient, scalable, and accessible back-end systems. At 3E, you will have the opportunity to work on meaningful projects that contribute to the advancement of renewable energy technologies and digitalization.

Responsabilities

  • Develop, test, and maintain robust, performant, and scalable back-end codebase in accordance with design and product requirements.
  • Identify and optimize performance bottlenecks in the application (and MySQL db) using best practices and techniques.
  • Use Polylith, Reitit, Malli to build APIs which are efficient and maintainable.
  • Design and develop efficient business-logic processors that act on data.
  • Conduct thorough code reviews and enforce good back-end practices to ensure quality and maintainability of code.
  • Collaborate with multidisciplinary teams of developers, scientists, renewable energy architects, electrical engineers, and sales enthusiasts to achieve project goals (in-person or via email/MS Teams).
  • Track project evolution (Jira).
  • Maintain a codebase that is easy to understand, modify, and extend, and adhere to coding standards and best practices.

Requirements

To fulfil this role we are looking for someone with:

  • Minimum of 3 years of experience in Clojure OR significant open-source contributions which can show a significant level of skill.
  • A proven track record of optimizing performance bottlenecks, enforcing good back-end practices.
  • Good understanding of performance optimization techniques in the context of Clojure & MySQL.
  • Product-based experience - supporting and modifying a product through several years - living with the decisions of the past and building on top of them.
  • Experience with refactoring a codebase as new features are written.

Bonus points for:

  • Good profiling skills (JVM profiler).
  • Other lisp languages (e.g SBCL).
  • Knowledge of Docker

Benefits

Our offices are hidden in the centre of Brussels with a view on a pond, with ducks and a heron bringing a regular visit. In addition to a stimulating atmosphere in a highly motivated group of people, 3E offers a unique opportunity to further develop yourself in a company/team with an ambitious growth plan, delivering innovative services.

Furthermore:

  • Flexible & gliding working hours
  • Open to fully remote candidates
  • An international environment with colleagues of 25+ nationalities and projects in over 100 countries.
  • An open-minded company where everybody can bring their ideas to the table

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About the role

January 21, 2026

Full Time

Company

January 22, 2026

Flexible

3E

3e.eu

  •  Brussels, Belgium

Minimum of 3 years in Clojure or significant open-source contributions

UTC+01:00

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