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For Companies At a Glance
- Tasks: Design and develop a large-scale SIP platform with modern AI integrations.
- Company: Established UK tech company known for innovation and strong engineering culture.
- Benefits: Enjoy 24 days annual leave, private medical insurance, and birthday off.
- Why this job: Join a collaborative team and make a real impact on mission-critical communications.
- Qualifications: 5+ years in software development, especially with SIP/VoIP and Python.
- Other info: Hybrid work model with excellent career growth opportunities.
Do you have the skills to fill this role? Read the complete details below, and make your application today.
Location: Guildford (Hybrid – must be UK-based and within a two-hour commute)
Contract: Full-time, Permanent
Salary: £55,000 – £65,000 (depending on experience)
The Opportunity
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 CVs.
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 Guildford 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 Guildford
✨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 job opportunities that aren't even advertised.
✨Tip Number 2
Show off your skills! Create a portfolio or GitHub repository showcasing your projects and contributions. 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 practising common technical questions and coding challenges. We recommend using platforms like LeetCode or HackerRank to sharpen your skills and boost your confidence before the big day.
✨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 Guildford
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! Share your passion for software development and why you're excited about this opportunity at StudySmarter. Let us know how you can make an impact on our SIP platform and services.
Apply Through Our Website: We encourage you to apply through our website for a smoother application process. It helps us keep everything organised and ensures your application gets the attention it deserves. Don’t miss out on this chance!
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, and the related protocols mentioned in the job description. Be ready to discuss your experience with Python, RESTful APIs, and any frameworks like Flask or Django. The more you can demonstrate your technical expertise, the better!
✨Showcase Your Problem-Solving Skills
Prepare to share specific examples of how you've tackled complex issues in previous roles. Think about times when you had to troubleshoot SIP/RTP problems or enhance existing platforms. This will show that you can think critically and contribute to their mission-critical communications platform.
✨Collaborate and Communicate
Since this role involves working closely with other developers and stakeholders, be ready to discuss how you approach collaboration. Share experiences where you’ve successfully worked in a team environment, highlighting your communication skills and ability to deliver high-quality solutions together.
✨Understand Their Culture
Research the company’s engineering culture and values. Be prepared to discuss how your own values align with theirs, especially regarding professional development and innovation. Showing that you’re a good cultural fit can set you apart from other candidates.
