Backend Software Engineer - Golang

1global; Lisboa; Hybrid; EUR 60,000 - 90,000; Full time

Benefits offered by this job

Growth opportunities

International exposure

Professional development

Global projects

Job summary

1GLOBAL is looking for a backend engineer to join our Lisbon-originating team working on Network API, xSIM Management System, and Recording Platforms. You will contribute to scalable, secure architectures and end-to-end feature delivery.

We value 3+ years of backend experience, strong Go or Java, and hands-on with databases and microservices. This role welcomes remote-friendly, international collaboration and ongoing learning within a fast-growing telecom technology company.

Qualifications

• 3+ years backend development experience, preferably Go.
• Strong concurrency and async workflows experience.
• RESTful APIs design and performance optimization.
• Experience with relational and NoSQL databases (PostgreSQL, Redis, MongoDB).
• Experience with tests: unit/integration/benchmarks (TDD).
• Familiar with gRPC, WebSockets, TCP/UDP networking.
• Experience with microservices and distributed systems.
• DevOps practices: Docker, CI/CD, and IaC.
• Proficient English communication for remote async environment.

Responsibilities

• Provide accurate effort estimates for roadmap planning.
• Design scalable, secure, fault-tolerant architectures.
• Develop features across Network API, xSIM, and Recording Platforms.
• Write and maintain tests and contribute to code reviews.
• Create and maintain technical docs.
• Collaborate with team for smooth development processes.
• Ensure end-to-end feature delivery and observability.

Skills

Go

Java

RESTful APIs

Microservices

CI/CD

Docker

Kubernetes

Distributed systems

English

Concurrency

Tools

PostgreSQL

Redis

MongoDB

gRPC

WebSockets

Kafka

AWS

GCP

Job description

About Us

1GLOBAL is a technology-driven global mobile communications provider helping enterprises and consumer brands deliver seamless connectivity worldwide. Powered by a best-in-class telecom platform, proprietary eSIM technology, and its own mobile core network across 15 countries, 1GLOBAL operates as a fully regulated telecommunications provider in 43 countries.

Founded in 2022, 1GLOBAL has rapidly become one of Europe's fastest-growing telecom technology companies, connecting more than 80 million people and devices globally. Our customers include leading banks, multinational enterprises, global retailers, travel companies, payment service providers, and digital-first businesses.

Headquartered in the Netherlands, with R&D hubs in Lisbon, Berlin, and São Paulo, 1GLOBAL employs over 550 professionals across 16 countries. With annual revenues exceeding US$200 million and a strong track record of profitability, we continue to invest in innovation, infrastructure, and international expansion as we redefine the future of global mobile connectivity.

About the Team

You will be joining a dynamic team at the forefront of developing and maintaining our Network API, xSIM Management System, and Recording Platforms. The Network API powers critical systems and services that enable the creation, configuration, and real-time monitoring of subscriber configurations across a wide array of business scenarios. These include enterprise solutions, IoT deployments, regulatory compliance, and recording services, ensuring seamless connectivity for everyone and everything. Our xSIM Management System is a high-performance, low-latency platform designed to handle hundreds of transactions per second, keeping all xSIMs accurately updated in real time. Meanwhile, our Recording Platforms deliver robust Mobile Compliance & Recording capabilities tailored for financial institutions, automatically capturing client and employee interactions either on-premises or through our secure cloud infrastructure.

We run a multi-site platform, following strict security requirements, provide the service to customers around the world and manage millions of subscriber profiles. We embrace a highly collaborative and diverse environment, value teamwork, autonomy and hold ourselves accountable for our deliverables and customer success.

We are open to hiring for this position in São Paulo, Brazil. The successfully hired candidate will receive onboarding and training in Lisbon, Portugal; gaining valuable skills while experiencing one of Europe’s most dynamic and renowned cities.

About the Role

• Provide accurate effort estimates to support roadmap planning and effective expectation management.


• Design and implement resilient, scalable, secure, and fault-tolerant architectures to ensure system reliability and performance.


• Develop new features and support existing systems across the Network API, xSIM Management System, and Recording Platforms.


• Contribute with small, incremental enhancements that seamlessly integrate into the established codebases.


• Maintain and update existing solutions to keep them modern, efficient, and reliable.


• Collaborate with team members to ensure smooth development processes and shared understanding.


• Write and maintain comprehensive tests to ensure fast regression and reliable validation of new features.


• Implement procedures and metrics to enable effective monitoring and observability of platform contributions.


• Participate in code reviews to promote high standards of code quality, readability, and maintainability.


• Take ownership of the quality and outcomes of your work, ensuring fully functional end-to-end flows.


• Create and maintain accurate, up-to-date technical documentation.


• Actively contribute to team discussions, with a mindset for continuous improvement and openness to new ideas or technologies.

About You

Must Have

• 3+ years of professional experience in backend development, preferably with Go (Golang). Strong Java experience with willing to learn Go is also welcome.


• Strong understanding of concurrency models, with practical experience in implementing asynchronous workflows, inter-process communication, and synchronisation techniques.


• Skilled in designing, building, and consuming RESTful APIs, following best practices for API design and performance optimisation.


• Proven experience working with databases, both relational (e.g., PostgreSQL) and non-relational (e.g., Redis, MongoDB, DynamoDB), including data modelling, query optimisation, and performance tuning.


• Experienced in writing unit tests, integration tests, and benchmarks, with a test-driven development mindset.


• Comfortable with networking protocols and distributed communication patterns (e.g., gRPC, WebSockets, TCP/UDP).


• Experienced in building scalable microservices architectures and distributed systems.


• Knowledgeable in applying software engineering best practices and design patterns for maintainable, testable code.


• Skilled in using DevOps tools and practices, including Docker, CI/CD pipelines, and Infrastructure as Code.


• Familiar with Git workflows and collaborative development processes such as pull requests, code reviews, and agile methodologies.


• Demonstrated accountability for technical outcomes and ownership of end-to-end feature delivery.


• Effective communicator in English, both written and verbal, suitable for a remote and largely asynchronous work environment.

Nice to Have

• Proficient in writing idiomatic Go code, with solid understanding of the language’s core features such as interfaces, structs, composition, and error handling.


• Competent in profiling and performance tuning using Go’s built-in tools such as pprof and trace, with a focus on optimisation.


• Demonstrated experience with event-driven architectures, including the implementation of producers and consumers using platforms like Kafka, RabbitMQ, or ActiveMQ.


• Solid hands-on experience deploying, monitoring, and maintaining applications on Kubernetes.


• Working knowledge of cloud platforms (e.g., AWS, GCP, Azure, Oracle Cloud) with experience deploying cloud-native applications.


• Hands‑on experience with observability and monitoring tools like Prometheus and Grafana.


• Experience with MSML and SIP is a strong plus.

Why 1GLOBAL?

• Growth Opportunities: Advance your career in one of the fastest growing telecommunications companies, expanding over 50% year-on-year under the leadership of successful tech entrepreneurs.


• Major Transaction Exposure: Be in the driver’s seat for transactions that will have an impact on the future telco industry.


• Work with a Talented Team: From the Board and the Founders to the Senior Management Team, you will collaborate daily with the most capable and renowned external advisors and constantly being exposed to talented and driven individuals.


• Dynamic Work Environment: Thrive in a collaborative, fast-paced workplace where innovation is encouraged, and every contribution counts.


• Professional Development: Work alongside industry experts to enhance your skills and knowledge in a cutting-edge field.


• International Experience: Gain opportunities to work in different 1GLOBAL offices around the world as you grow within the company.


• Open Communication Culture: Join a team where your ideas are heard, and open dialogue is encouraged, fostering a supportive and transparent work environment.


• Get Things Done Attitude: Be part of a results-driven team that values efficiency, creativity, and the drive to make a tangible impact in the industry.

1GLOBAL is an equal opportunity employer, we value your character as much as your talent. Diversity drives our innovation, and we offer a collaborative, dynamic, and international work environment. We are excited for you to join our mission to revolutionise connectivity globally.