Senior Software Engineer – Legacy Codebase Migration

This is a fully remote position, open to applicants in New York.

📋 Description

• Design, execute, assess, and analyze complex codebase migration and modernization initiatives.

• Examine mature production systems to establish safe and technically sound migration strategies.

• Review the architecture of legacy applications, including dependencies, APIs, databases, build systems, and infrastructure.

• Identify areas of technical debt, compatibility issues, migration risks, and concealed dependencies.

• Formulate migration strategies for extensive, interconnected production environments.

• Evaluate migrations involving languages, runtimes, frameworks, applications, databases, data layers, infrastructure, cloud services, CI/CD, build tools, APIs, integrations, authentication, identity, repositories, dependencies, toolchains, and testing.

• Assess behavioral equivalence, compatibility, data integrity, security, performance, reliability in production, maintainability, and readiness for production.

• Review deployment architecture, operational dependencies, scalability, staged rollouts, rollback procedures, observability, and resilience strategies.

• Analyze unfamiliar codebases and identify subtle migration failures.

• Evaluate proposed technical decisions against realistic enterprise constraints.

• Identify missing dependencies, edge cases, regression risks, and unsafe assumptions.

• Provide clear, technically rigorous feedback on migration strategies and implementations.

⛳️ Requirements

• A minimum of 5 years of professional software engineering experience, preferably at the Senior, Staff, Principal, Lead, or equivalent level.

• Significant hands-on experience in executing large-scale production migrations.

• Personally contributed to or managed substantial technical aspects of complex modernization projects.

• Strong experience with mature systems that involve technical debt, intricate dependencies, legacy integrations, and considerable regression risks.

• In-depth knowledge of compatibility, testing, observability, staged rollouts, rollback strategies, and behavioral equivalence.

• Ability to deeply analyze unfamiliar codebases and identify subtle migration failures.

• Experience with one or more major migration categories, including languages, frameworks, databases, APIs, infrastructure, CI/CD, authentication, repositories, testing, or dependencies.

• Experience in modernizing systems within high-reliability environments such as financial services, fintech/payments, trading, insurance, healthcare, telecom, large technology companies, or similar sectors is particularly advantageous.

• For mainframe modernization projects, experience with COBOL, z/OS, CICS, JCL, DB2, VSAM, batch processing, and COBOL-to-Java/Python migration is especially valuable.

• Must be able to complete work without utilizing confidential or proprietary information from any employer, client, institution, or other third party.

• H1-B and STEM OPT support is not available for this position.

🏝️ Benefits

• Fully remote work environment.

• Flexible scheduling based on project needs.

• Opportunity to join a talent network with potential for ongoing project work.