Hybrid – Porto (3 days office / 2 remote) Freelance contract – 6 months (3+3) with potential long-term integration Start: ASAPWe’re looking for a Senior Backend Engineer to join a fast-growing company in the EV charging industry, helping design and scale the backend systems powering next-generation charging infrastructure.You will work closely with product and engineering teams to build high-performance and reliable backend services in a modern microservices architecture.What you’ll be doingDesign and develop scalable backend microservices using Java and Spring BootDeploy and maintain services in AWS cloud environmentsWork with event-driven systems using Kafka or RabbitMQContribute to architecture discussions and system improvementsEnsure reliability, security, and performance of backend systemsParticipate in code reviews and technical decision-makingCollaborate with cross-functional teams to deliver new featuresTech StackJavaSpring BootAWS (EC2, S3, Lambda, RDS)DockerKubernetesKafka / RabbitMQMicroservices architectureRelational & NoSQL databasesReactRequirements4-6+ years of backend development experienceStrong experience with Java and Spring BootKnowledge of ReactExperience building microservices architecturesHands-on experience with AWSExperience with Docker and KubernetesFamiliarity with messaging systems (Kafka or RabbitMQ)Strong problem-solving and communication skillsFluent English