Java Engineer – Application / Database Modernization

Job description

Mactores is the agent-native AWS modernization firm. Most modernization work doesn't ship, it stalls in pilots, slips a year, or lands at three times the budget. We exist to ship it: production systems running, legacy retired, outcomes measured. Our delivery is built on Aedeon, the agent platform built by Mactores' founders' sister company, which absorbs the repetitive 60–70% of engagement work, discovery, dependency mapping, validation, test generation, that traditional consulting bills human hours against. Forward-deployed engineers own the rest: architecture, judgment, and cutover, on dates we commit to in the contract. Enterprises stuck on Oracle carry license renewals, vendor-specific SQL nobody wants to touch, and application layers welded to the database underneath them. This role sits in our Application & Database Modernization pillar: you'll work an Oracle-to-PostgreSQL migration where Aedeon handles the mechanical conversion at scale and you own what the tools can't the refactoring judgment inside large enterprise Java codebases. You'll rewrite the SQL the application actually depends on, align it with the modernized schema, prove functional parity, and see the application through production cutover. Not a proof of concept. A system that ships. ### What you will do? - Analyze and remediate large enterprise Java codebases — replace legacy and database-specific SQL constructs with modern, standards-compliant SQL. - Convert embedded SQL in Java services and MyBatis XML mappers: rewrite vendor-specific functions, sequences, pagination logic, dynamic SQL, and error-handling patterns. - Work closely with schema and database migration engineers so application-layer SQL lands aligned with the modernized target schema. - Refactor Java transaction logic, error handling, drivers, and ORM/DAO layers to match the behavior of modern databases. - Run unit, integration, and performance testing to confirm functional parity and hit performance SLAs post-modernization. - Support production cutover — validation, monitoring setup, rollback planning, and stabilization until the system holds. - Produce engineering documentation that outlives the engagement: SQL remediation guides, code-migration runbooks, troubleshooting guides, and knowledge-transfer material for customer teams. - Work across distributed teams (US and India) and with customer SMEs to keep business logic aligned and the modernization on track. ### What are we looking for? - Bachelor's degree in Computer Science, Engineering, or a related field. - 5+ years of professional Java development experience (Spring, JDBC, MyBatis/Hibernate or equivalent). - Experience with application modernization, database migrations, or large-scale refactoring initiatives. - Strong SQL expertise you can analyze, interpret, optimize, and rewrite complex SQL embedded in Java applications. - Deep understanding of JDBC, ORMs, Java transaction patterns, and database-driven application flows. - Experience on enterprise-grade, high-performance applications with complex data interactions. - Strong communication skills and the ability to work with global distributed teams in US time zones. ### You will be preferred if - Experience with PostgreSQL, Aurora PostgreSQL, or modernization from legacy databases such as Oracle, SQL Server, or DB2. - Exposure to automated code-refactoring tools or GenAI-assisted remediation workflows. - Familiarity with CI/CD environments, performance testing tools, and observability stacks. - Consulting or professional services experience delivering fixed-timeline modernization projects. ### How we work? Agents do the repetitive 60–70% of the work a traditional consulting engagement of equivalent scope staffs humans for. Engineers do the rest, and the rest is the interesting part. You won't spend months grinding through mechanical SQL conversion; Aedeon and its regression harness cover that. Your hours go to refactoring judgment, risk tradeoffs, production cutover, and post-cutover optimization. We commit to delivery dates and absorb the overage cost for delays inside our control, which means the engineering has to be right the first time. That's the job.