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For Companies At a Glance
- Tasks: Design and develop a cutting-edge SIP platform with innovative integrations.
- Company: Join a leading UK tech company known for its strong engineering culture.
- Benefits: Enjoy 24 days of leave, private medical insurance, and high street discounts.
- Why this job: Make a real impact in a collaborative environment with modern technologies.
- Qualifications: 5+ years in software development, especially with SIP/VoIP and Python.
- Other info: Hybrid role with excellent career growth opportunities.
The predicted salary is between 55000 - 65000 £ per year.
An established UK technology company is expanding its Software Development Team and is looking for an experienced Senior Software Developer to help evolve a large-scale, enterprise-grade SIP platform and its associated REST APIs. This is an excellent opportunity to work on complex, real-world systems in a collaborative, technically strong environment. You’ll contribute to the ongoing development of a mission-critical communications platform, build value-added services, and work with modern AI-driven integrations. The organisation is known for its strong engineering culture, long-term customer partnerships, and commitment to professional development. You’ll be joining a supportive, innovation-led environment where your ideas and expertise will have a real impact.
Role Summary
- Designing, developing, and enhancing an existing enterprise SIP platform and supporting services
- Building new value-added services and capabilities around the core platform
- Developing integrations with third-party systems, including AI-based voice recognition, transcription, and sentiment analysis services
- Ensuring secure software design and development at both application and network levels
- Analysing, troubleshooting, and resolving SIP/RTP and platform-level issues
- Contributing to secure development processes, policies, and compliance with standards such as ISO 27001 and PCI-DSS
- Collaborating closely with other developers and stakeholders to deliver high-quality, scalable solutions
Essential Skills & Experience
- SIP / VoIP and related protocols (SDP, RTP, RFC2833 / RFC4733, etc.)
- Python or another object-oriented language (5+ years)
- Object-oriented design principles
- HTTP / RESTful APIs
- Flask or Django, including Jinja, Pytest, SQLAlchemy, and Marshmallow
- Secure systems design and development (software and network level)
- SIP/RTP troubleshooting using tools such as Wireshark
- Git / GitHub (or similar version control systems)
- Docker containerisation
- Linux (Ubuntu-based) environments
- Full driving licence with car due to the client's location
Desirable Skills
- FreeSWITCH (configuration and, ideally, source code)
- C / C++ (for open-source troubleshooting or minor code changes)
- Kamailio
- Auth0 / OAuth 2.0
- MongoDB and/or MySQL
- CI/CD pipelines (e.g. GitHub Actions)
- Kubernetes / ArgoCD
- WebRTC
Benefits
- 24 days’ annual leave plus bank holidays
- Pension, Life insurance, Private medical insurance
- Birthday and volunteering day off
- High street discount vouchers
Thank you for taking the time to apply to OPR Resourcing Specialists. If your application is successful you will be contacted within 7 days. We apologise but due to the high volume of applications we receive we are unable to provide feedback on individual CV's. Regrettably, we are unable to offer Right to Work Sponsorship. If you do not currently have the Right to Work in the UK or will need additional support to extend your current Right to Work status, your application cannot be considered. Please note that by applying for the above job it will be understood that you accept our Terms of Business and Privacy Policy which can be found on our website on the page "Find A Job".
Senior Software developer in Surrey employer: OPR Resourcing Specialists
Contact Detail:
OPR Resourcing Specialists Recruiting Team
StudySmarter Expert Advice 🤫
We think this is how you could land Senior Software developer in Surrey
✨Tip Number 1
Network like a pro! Reach out to your connections in the tech industry, especially those who work at companies you're interested in. A friendly chat can sometimes lead to insider info or even a referral.
✨Tip Number 2
Show off your skills! Create a portfolio showcasing your projects, especially those involving SIP/VoIP and REST APIs. This gives potential employers a taste of what you can do and sets you apart from the crowd.
✨Tip Number 3
Prepare for interviews by brushing up on common technical questions related to Python, SIP protocols, and secure systems design. Practising with mock interviews can help you feel more confident when it’s your turn to shine.
✨Tip Number 4
Don’t forget to apply through our website! It’s the best way to ensure your application gets seen. Plus, we love seeing candidates who take the initiative to connect directly with us.
We think you need these skills to ace Senior Software developer in Surrey
Some tips for your application 🫡
Tailor Your CV: Make sure your CV is tailored to the Senior Software Developer role. Highlight your experience with SIP/VoIP protocols and any relevant projects you've worked on. We want to see how your skills align with what we're looking for!
Showcase Your Skills: Don’t just list your skills; demonstrate them! Include specific examples of how you've used Python, Flask, or Docker in your previous roles. This helps us understand your practical experience and how you can contribute to our team.
Craft a Compelling Cover Letter: Your cover letter is your chance to shine! Use it to explain why you're passionate about this role and how your background makes you a great fit. We love seeing enthusiasm and a bit of personality in applications!
Apply Through Our Website: We encourage you to apply through our website for a smoother process. It helps us keep track of applications and ensures you’re considered for the role. Plus, it’s super easy to do!
How to prepare for a job interview at OPR Resourcing Specialists
✨Know Your Tech Inside Out
Make sure you brush up on your knowledge of SIP/VoIP protocols and the specific technologies mentioned in the job description. Be ready to discuss your experience with Python, RESTful APIs, and any relevant frameworks like Flask or Django. This will show that you're not just familiar with the tech but can also apply it effectively.
✨Showcase Your Problem-Solving Skills
Prepare to discuss specific challenges you've faced in previous roles, especially related to troubleshooting SIP/RTP issues. Use examples that highlight your analytical skills and how you resolved complex problems. This will demonstrate your ability to think critically and contribute to the team.
✨Emphasise Collaboration
Since the role involves working closely with other developers and stakeholders, be ready to talk about your experience in collaborative environments. Share examples of successful projects where teamwork was key, and how you contributed to a positive engineering culture.
✨Ask Insightful Questions
Prepare thoughtful questions about the company's engineering culture, ongoing projects, and future developments. This shows your genuine interest in the role and helps you assess if the company is the right fit for you. Plus, it gives you a chance to engage with the interviewers on a deeper level.
