Job Description
Senior Developer (.NET) - D&A (m/f/d)

IN SHORT

The Senior Developer has multiple responsibilities within the organization. Their time is broken down to software delivery and junior developer coaching responsibilities. Software delivery responsibilities will vary over time but are focused on the technical leadership, design and development of applications used in the trade lifecycle. It is expected that a Senior Developer will work on a portfolio of different software products during their time in the organization and will coach different individuals in their career.

WHAT WILL YOU DO

  • Work with the Vertical Leads (Delivery, Technical, QA, Architecture and Functional) to align delivery of work and hit timelines agreed with the business
  • Liaise with, and support, key business stakeholders from across the end user community
  • Work with the Technical and Architecture lead to support the technical engineering of a portfolio of applications and ensure that work adheres to design best practices
  • Understand the technical needs/dependencies with other applications/teams and manage these with the Lead Developers and Architects to ensure the correct technical solutions are implemented
  • Strive for architecture and design consistency and liaise with the Architecture team to help influence these principles. Perform code reviews or ensure that adequate code reviews are performed by the team
  • Work with the Vertical Tech Lead and Architects to identify technical debt and ensure that it is addressed and communicated to key stakeholders such that it can be dealt with as part of the BAU process. Promote the consistency of development technologies across our teams improving the overall landscape in the best interests of SEFE.
  • Work with the Architects to create and deliver technology roadmaps for the software solutions, aligning them with the technology roadmap and Architecture principles for the department
  • Contribute to the software development roadmap, patterns, and principles
  • Design, develop and deliver high-quality, test-driven object-orientated software

WHAT WILL YOU BRING

Professional Skills

  • Self-starter with strong commercial awareness and a focus on delivering business value; able to work independently and adapt quickly in a fast-changing environment.

  • Excellent interpersonal and communication skills (verbal and written), with the ability to explain complex technical topics to non-technical stakeholders and collaborate effectively across teams.

  • Proven technical authority and credibility to guide and influence a talented development team; experienced in coaching and mentoring junior developers (or motivated to grow into this responsibility).

  • Strong problem-solving mindset with the ability to balance ideal technical solutions against practical business requirements.

  • Extensive experience as an Enterprise Developer on complex projects using C#, SQL Server, and web UI frameworks such as Angular.

  • Background in data-intensive or trading environments (e.g. commodities, financial, betting). Experience with Endur or other ETRMs and their .NET APIs (Open Components) is an advantage.

 

Technical Expertise

  • Solid knowledge of Microsoft .NET, C#, and WebAPI; experience with OAuth2 is an advantage.

  • Strong Microsoft SQL Server experience; familiarity with MongoDB beneficial.

  • Understanding of Design Patterns, SOLID principles, and Test-Driven Development (TDD) using SpecFlow/ReqnRoll.

  • Experience with CI/CD processes (Azure DevOps preferred) and cloud platforms, ideally Azure, including Infrastructure as Code (Terraform).

  • Knowledge of messaging technologies (e.g. RabbitMQ, Kafka).

  • Experience with modern web technologies such as Angular and TypeScript.

  • Familiarity with the Microsoft BI Stack (SSAS, SSIS, SSRS, Power BI) is an advantage.

 

Education / Qualifications

  • Qualifications or equivalent experience in a Scientific, Computing, or Engineering discipline.

  • Relevant professional certifications are an advantage.

ABOUT US

Securing Energy for Europe – it’s a simple statement, with a bold ambition. SEFE is not just our name, but also encompasses everything that drives us. To accomplish this, we’re taking immediate action to secure gas supply – but also looking forward, to explore our role in the European energy transformation and how we can contribute to a stable and sustainable future.  

 

SEFE, an international energy company, ensures the security of supply and drives the decarbonisation of its customers. SEFE’s activities span the energy value chain, from origination and trading to sales, transport, and storage. Through its decades-long expertise in trading and the development of its LNG business, SEFE has become one of the most important suppliers to industrial customers in Europe, with an annual sales volume of 200 TWh of gas and power. Its 50,000 customers range from small businesses to municipalities and multinational organisations. By investing in clean energies and especially in the hydrogen ecosystem, SEFE is contributing to the energy transition. The company employs around 2,000 people globally and is owned by the Federal Government of Germany.

 

Our international teams work across locations in Europe, Asia, and North America. We’re passionate about energy and the important role it can play in shaping a better future.  

 

Securing energy – now and for the future.

OUR BENEFITS

We’re committed to creating an inclusive environment that embraces diversity and fosters the development of knowledge, skills, and experience. Whatever your role, you’ll find an open, welcoming atmosphere that empowers you, and recognises your contribution. 

 

In return we offer a competitive starting salary supported by a comprehensive range of financial, lifestyle and wellness benefits with the flexibility to follow a hybrid working model. 

  • bonus earning potential
  • non-contributory pension with 10% employer contribution
  • 25 days holiday plus bank holidays and volunteering days
  • buy / sell holidays
  • life assurance
  • medical and dental insurance (family cover)
  • range of optional flexible benefits

 

We are committed to supporting your career growth with opportunities to develop both your knowledge and experience through a blended approach to learning. 

 

Join SEFE and help us secure energy supply across Europe and shape a better, more sustainable tomorrow. 

 

#LI-JL1

Information at a Glance
Job Title:  Senior Developer (.NET) - D&A (m/f/d)
Job Country:  United Kingdom
Job Location:  London, United Kingdom
Posting Start Date:  08/10/2025
Business Function:  Information Technology
Contract Type:  Permanent