Senior Software Engineer

About the role

Upwork is seeking a Senior Software Engineer to join the tax engineering team in Lisbon. You will design and maintain critical backend services for tax calculation and payment processing while contributing to frontend workflows that support our global platform.

Key facts

What you'll do

• Develop and maintain backend systems focused on VAT, sales tax, and withholding accuracy.
• Build and support frontend interfaces using modern JavaScript frameworks for internal and customer-facing tools.
• Create and manage API integrations with third-party tax engines and payment processors.
• Collaborate with product, finance, and compliance departments to translate regulatory requirements into technical solutions.
• Perform code reviews and utilize AI-assisted development tools to maintain high standards of code quality and velocity.
• Troubleshoot production issues and implement long-term fixes to improve system reliability.

Requirements

• Professional backend engineering experience using Java.
• Proficiency in building RESTful APIs and working with relational databases.
• Experience deploying and managing services on AWS.
• Practical experience contributing to frontend applications with Vue.js or similar frameworks.
• Ability to own projects from inception to completion while working with cross-functional teams.
• Familiarity with AI-enabled coding tools like GitHub Copilot or Cursor.

Nice to have

• Background in fintech, payments, or tax compliance domains.

Skills & tools

• Java
• Vue.js
• AWS
• RESTful APIs
• Relational Databases
• AI-assisted development tools (GitHub Copilot, Cursor)

Practical notes

• This role requires 3 days of in-office attendance once the Lisbon hub is fully operational by Q4 2026.
• Initial employment will be managed through a partner, with potential for direct employment by Upwork as the hub matures.
• Interviews may be recorded via BrightHire for internal review; candidates may opt out of this recording during scheduling.
• The compensation package includes an annual bonus plan and long-term equity incentives.