Senior Integration Engineer (Java Proxy)

This a Full Remote job, the offer is available from: Europe Quick summary Location: Lima, Peru (Hybrid) or LATAM (with travel to Lima). ⏰ Time Zone: Requires overlap with European afternoon (Morning in Peru). Spanish Fluency is mandatory. You will be the technical bridge to the client's engineering team in Peru and the European production team. Experience: 8+ years of experience in backend development, with a specialization in System Integration, Legacy Decoupling, Migrations, and Resilience Patterns. ️ The Mission: You will build the centralized Gateway/Proxy that replaces direct database & API connections. You are not just extracting data; you are building the new data backbone that serves existing legacy applications when the old ERP (Oracle HCM & Ofiplan 9.0) is turned off. Salary: Gross (B2B) 4000$ ~ 6000$ / month. About us BB Agency is a partner for digital evolution, blending creativity and technology to drive meaningful growth. We collaborate with companies focused on real human needs, shaping brands, experiences, and products that impact millions daily. Founded in 2012 on Island Krk, Croatia, we've grown into a fully remote agency with a global team of 40+ members. We believe in learning by doing, open communication, and pushing boundaries to deliver our best work. Our clients range from tech SMEs to corporations and funded startups in SaaS, finance, healthcare, and more. We’ve partnered with names like AWS, Deloitte, BNP Paribas, Intercorp, ShipBob, Crisp, and CloudZero, among many others. Job description We are seeking a battle-hardened Senior Integration Engineer to join our specialized "Proxy Squad." We are replacing a massive ecosystem of Oracle HCM and Ofiplan 9.0 legacy systems with a new custom-built HR & Payroll cloud software. The Challenge: We cannot simply turn off the old systems. Dozens of satellite applications in the enterprise environment still depend on them. Your Solution: You will build the Proxy Layer, a high-performance Java Gateway that sits between our new, clean, modern microservices and the messy legacy world, acting as the new "Source of Truth” for legacy apps that currently consume data from Oracle HCM and Ofiplan 9.0. You are the "Digital Archaeologist" who will reverse-engineer undocumented API endpoints, migrate Oracle HCM and Ofiplan 9.0 data to a new system, connect to SQL Server (Microsoft) and Oracle DBs, handle direct JDBC Connections, and ensure that zero bad data infects the new platform. Your service will intercept data requests, decoupling the satellite apps from the underlying database and APIs. You are responsible for ensuring business continuity for the entire enterprise ecosystem during migration to new HR & Payroll solutions. Your Responsibilities • Build the Gateway: Design and develop a robust Proxy Service (Java 17+ / Spring Boot) that acts as the new "Source of Truth” between old legacy apps and the new HR & Payroll system. • The Anti-Corruption Layer: Implement strict data sanitation and transformation. You ensure that the complex, messy data from the legacy world is cleaned before it enters the new HR & Payroll system, and vice versa. • Build the "Facade": Ensure the Proxy Service provides data in a format these legacy apps understand (preserving old contracts), even as we migrate the underlying storage to modern cloud infrastructure. • Reverse Engineering: Analyze undocumented SQL Stored Procedures and database schemas to understand exactly what data the satellite apps are currently reading. • Resilience Engineering: Implement Circuit Breakers (Resilience4j), Retry Logic, and Caching. The legacy system will be slow; your proxy must ensure the new system never crashes because of it. • Decouple the Database: Existing legacy apps currently query the Ofiplan DB directly. You will design and expose new APIs (REST/SOAP) via the Proxy to serve this data, effectively breaking the direct dependency on the old database. • Spanish Technical Communication: You will be the primary technical contact for the client’s engineering team in Peru. You must be able to discuss database locks, API contracts, and debugging sessions in Spanish. Preferred experience • 8+ years of Backend Experience: Deep expertise in Java 17+ and the Spring Ecosystem. • Integration Specialist: You are not afraid of SOAP/XML, WSDL parsing, and JAXB. You know how to handle "ugly" enterprise protocols. • Database Dependency Breaking: Experience analyzing direct JDBC connections/Stored Procedures and replacing them with clean API layers. • Resilience Patterns: Hands-on experience with Resilience4j, Rate Limiting, and Asynchronous processing to handle slow upstream systems. • Legacy Decoupling: Experience with the Strangler Fig Pattern. You know how to slowly migrate traffic from a monolith to a microservice without downtime. • Tooling Mastery: Expert-level skills in SoapUI, Postman, and network sniffing (Wireshark) to map out existing traffic. • War Stories: Experience in Banking, Finances, or Insurance migrations where you had to refactor direct-database integrations and integrate with 10+ year old systems. • Language: Spanish fluency is mandatory for this role. English must be professional. What to expect • Flexibility - We already operate in multiple time zones and have been doing it for years. We have standard 40-hour work weeks. While our agency working hours are from 9 am to 7 pm CET, you’ll have the freedom to work flexible hours and maintain a healthy work-life balance. Just make sure the portion of your working hours falls within the CET timeframe to sync with the production team. "Overlap" happens in the Lima Morning / European Afternoon. • Remote work - We like to think about ourselves as remote-natives. One of the perks of our remote team is that we genuinely trust you to get your job done. You can work from anywhere you see fit, as long as you have a decent internet connection. Since your primary job will be Integration with the legacy on-premises system, part of your working days will require you to visit the client location in Lima, Peru. We use HubStaff for time tracking and transparency into your work. • Culture - We value collaboration, openness, a willingness to learn, lead, and a curious nature. Our approach encourages mistakes as long as we are willing to learn from them, fostering a culture where growth comes from understanding and overcoming challenges. If you like to work in teams that value great work over loud voices, you are in the right place. • Autonomy and responsibility – You’ll be trusted to get things done efficiently and effectively. Hiring process • Pre-selection based on your application (We’ll review your experience, past projects, and integration skills). • Introductory call with HR to get to know you better. • Psychological evaluation. • Interview with our Development Team leadership. • Welcome to BB Agency. CompensationGross (B2B) 4000$ ~ 6000$ / month This offer from "BB Agency" has been enriched by Jobgether.com and got a 82% flex score. Apply tot his job