VoIP Engineer

You will help ensure our platform is secure, resilient, and high performing, with predictable behaviour under load and clear observability for troubleshooting and optimisation. This is a deeply technical engineering role where you will combine expertise in SIP/VoIP, OpenStack administration, IP networking, and firewalls to keep our voice platform robust and efficient. You will work across signalling and media, routing, firewalls and automation, with plenty of room to refine existing solutions, improve reliability, and reduce operational toil over time., * Design, deploy and operate FreeSWITCH-based voice workloads as part of a highly available, carrier-grade platform.

• Configure and maintain Kamailio as a SIP proxy/registrar for routing, load distribution and security policy enforcement.
• Administer and optimize OpenStack environments, including computer, networking and storage, with a focus on stability, capacity and security.
• Configure, operate and harden Mikrotik firewalls, including routing, NAT, VPN/IPsec and traffic shaping relevant to real-time voice.
• Design and maintain IP routing for SIP and RTP traffic, ensuring low latency, high availability, and clear traffic segmentation.
• Implement and manage IPsec tunnels and other secure connectivity mechanisms to integrate with partners, carriers, and customers.
• Monitor and troubleshoot end-to-end call flows across FreeSWITCH, Kamailio, network devices, and underlying infrastructure.
• Build and maintain automation, scripts and runbooks to streamline provisioning, configuration, upgrades and incident response.
• Contribute to improving observability of the platform (metrics, logs, traces) and use data to drive performance and reliability improvements.
• Document architectures, configurations, and operational procedures in a clear and maintainable way.

We are looking for a hands-on, curious, and self-driven engineer with strong VoIP, cloud infrastructure, and networking skills to join our technical organization as a VoIP Engineer. In this role, you will design, operate, and continuously improve the infrastructure that powers our real-time voice services, spanning FreeSWITCH, Kamailio, OpenStack, and critical routing and security components., * Several years of hands-on experience (+5 years) running infrastructure for VoIP, real-time communications, or telecom platforms.

• Strong practical experience with FreeSWITCH in production, including configuration, scaling and troubleshooting.
• Solid OpenStack knowledge with demonstrable experience in day-to-day administration, upgrades and problem resolution.
• Deep understanding of IP networking and routing, especially in the context of SIP and RTP (subnetting, routing protocols, QoS concepts).
• Experience configuring and operating Mikrotik firewalls in complex environments.
• Proven experience with IPsec and related secure connectivity technologies in production setups.
• Comfortable working with Linux systems in an operational context, including troubleshooting, scripting and basic performance tuning.
• Ability to analyse complex technical issues, structure problems, and drive them to resolution with a high degree of ownership.
• English and Spanish proficiency, both spoken and written, at a professional level, enabling effective collaboration and clear documentation.

Very Good To Have

• Experience developing or maintaining tooling in C# to support platform operations or integrations.
• Experience with Python for automation, scripting, and integration with APIs or internal tools.
• Broader Linux administration experience, including system hardening, package management and service supervision.
• Experience with Ansible for configuration management and repeatable infrastructure changes.

Enreach is a company that adds value to its customers and believes in the professional growth of people. We are the European market leader in IP telephony and Unified Communications as a Service (UCaaS). Thanks to our team of specialists in development, cloud, and real-time voice and video communications, we design and deliver a complete portfolio of collaborative technologies and convergent telecommunications services for businesses (Unified Communications, Contact Center Services, collaboration, Virtual PBX, SIP Trunking, etc.). We believe in collective leadership and build our project on foundations such as closeness, flexibility, respect, and innovation. What do we offer? * A stable project with a permanent contract and flexible compensation options, including meal vouchers, transportation, childcare, and private health insurance. * Flexible working hours with a shorter workday on Fridays. * We follow a hybrid organizational model that combines the work-life balance benefits of remote work with on-site collaboration in our Barcelona office (a minimum of 2 days per week), fostering team cohesion. * A collaborative environment where we encourage autonomy and the ability to propose improvements that truly make a difference (Holacracy). * Centrally located, modern, and bright offices. You can enjoy a spacious kitchen area, a relaxation zone, an arcade machine, and coffee, tea, and fruit available to you every day. If all of this sounds interesting to you and you would like to be a new member of our family, do not hesitate to apply for the vacancy! Are you ready to take on the challenge of create contact magic? At Enreach, we are committed to promoting equality in the workplace. We strive to ensure equal opportunities and actively work to remove any barriers to professional growth and development. It is important to us that everyone feels welcome and uniquely valued, which is why we focus on fostering a diverse and inclusive work environment. We celebrate our diversity, as it drives creativity, entrepreneurship, and innovation