Voice Core Engineer - IMS

First Point Group is recruiting for multiple Voice Engineer / Voice Core Engineer (IMS) on behalf of a leading global telecommunications company. This client works with multiple tier-1 operators so it is a great career development opportunity for you to work with telecom operators and projects. The successful candidate must have IMS Voice Core design (LLD / HLD) experience including delivery (integration and deployment). You will have the following technical experience - CS/IMS/5G Voice Core architectures, SIP, Diameter and SS7 etc).

PLEASE NOTE - sponsorship can not be provided. Candidates must live in Portugal with valid rights to work.

Why join?

• Immediate start (within 2-4 weeks) - perfect if you are immediately available / available soon


• Lisbon - hybrid working (only 2 days per week in office)


• This role offers the opportunity to shape large-scale Voice Core solutions across multiple international markets, working on cutting-edge technologies spanning CS, IMS, and 5G domains.


• You will act as a senior technical authority responsible for the design, integration, and delivery of advanced Voice Core solutions. You will play a key role in strategic technical analysis, solution design, and end-to-end system delivery, ensuring alignment with global architecture standards and 3GPP frameworks.

Key Responsibilities

• Lead design and specification of Voice Core hardware and software solutions


• Deliver integration, deployment, and expansion across Voice Core systems (MSS, MGW, STP, DRA, HSS, HLR, SBC, CSCF, TAS, UDR, AUSF, UDM, IBCF)


• Drive integration and acceptance testing for new releases and upgrades


• Produce low-level designs, implementation documentation, and solution guidelines


• Support end-to-end project delivery including planning, risk management, and reporting


• Define Work Orders and support change management processes


• Provide technical leadership, mentoring, and coaching to engineers


• Collaborate across architecture, operations, vendors, and customer teams

Required Experience & Skills

• Strong expertise in CS, IMS, and 5G Voice Core architectures (3GPP aligned)


• Deep understanding of telecom protocols: SIP, Diameter, SS7, MAP


• Knowledge of complementary technologies: HTTP2, REST, JSON, SOAP, TLS, SQL


• Experience across full system lifecycle (design → deployment → optimisation)


• Proven track record delivering multi-vendor, multi-country telecom projects


• Strong stakeholder communication skills in global environments

Qualifications

• Degree in Telecommunications, Computer Science, Electronics, or similar


• Understanding of telecom ecosystems including IP networking and cloud integration


• Experience integrating network, IT, and operational systems