Senior Software Engineer

Upwork Inc.’s (Nasdaq: UPWK) family of companies connects businesses with global, AI-enabled talent across every contingent work type including freelance, fractional, and payrolled. This portfolio includes the Upwork Marketplace, which connects businesses with on-demand access to highly skilled talent across the globe, and Lifted, which provides a purpose-built solution for enterprise organizations to source, contract, manage, and pay talent across the full spectrum of contingent work. From Fortune 100 enterprises to entrepreneurs, businesses rely on Upwork Inc. to find and hire expert talent, leverage AI-powered work solutions, and drive business transformation. With access to professionals spanning more than 10,000 skills across AI & machine learning, software development, sales & marketing, customer support, finance & accounting, and more, the Upwork family of companies enables businesses of all sizes to scale, innovate, and transform their workforces for the age of AI and beyond.

Since its founding, Upwork Inc. has facilitated more than $30 billion in total transactions and services as it fulfills its purpose to create opportunity in every era of work. Learn more about the Upwork Marketplace at Upwork.com and follow us on LinkedIn, Facebook, Instagram, TikTok, and X; and learn more about Lifted at Go-Lifted and follow on LinkedIn.

As a Senior Software Engineer on the tax engineering team, you will build and improve the services that power tax calculation across VAT, sales tax, and withholding for a global platform. You'll own meaningful pieces of the backend, contribute to frontend workflows, and collaborate closely with engineers, product, finance, and compliance partners to ship reliable, well-tested systems. This is a strong fit for someone who enjoys working through detailed business logic, integrating third-party providers, and steadily raising the quality of complex financial software.

Responsibilities:

• Build, extend, and maintain backend services for tax calculation and payments, focusing on accuracy, reliability, and clean, testable code.
• Contribute to frontend workflows using Vue.js or similar modern JavaScript frameworks to support internal tools and customer-facing experiences.
• Develop and maintain APIs and integrations with external payment processors and tax engines, improving performance, observability, and error handling.
• Partner with product, finance, tax, and compliance stakeholders to translate business and regulatory requirements into well-scoped technical work.
• Improve code quality through thoughtful testing, code reviews, and AI-assisted development workflows that increase velocity without sacrificing rigor.
• Investigate production issues, identify root causes, and deliver durable fixes that strengthen the reliability of tax and payments systems.

What it takes to catch our eye:

• Solid backend engineering experience with Java, including building RESTful APIs, working with relational databases, and deploying services on AWS.
• Working experience contributing to frontend applications using Vue.js or another modern JavaScript framework.
• Track record of owning project-level work end to end and collaborating effectively with cross-functional partners.
• Exposure to tax, fintech, payments, or another compliance-heavy domain is a plus, paired with a willingness to learn complex business rules quickly.
• Practical fluency with AI-enabled engineering tools such as GitHub Copilot or Cursor, with the judgment to review and validate outputs and a habit of sharing useful AI techniques with teammates.

Come change how the world works.

Upwork is establishing its first international operational hub in Lisbon, Portugal. The new office is expected to be fully operational by Q4 2026. This role will require 3 days in office once we have an office open.

This position will initially be employed through a partner to ensure a seamless hiring process while we establish the hub. Once the hub is established, there may be opportunities to transition to employment with Upwork, depending on business needs and other requirements. While employed by the partner, you’ll work as part of Upwork’s team, with access to our resources, culture, and growth opportunities.

Our partner will offer competitive benefits. When Upwork’s hub is established, we will be excited to offer employment and benefits directly as business needs require. 

Upwork is committed to building a diverse, inclusive, and equitable workforce. Employment decisions are made without regard to race, color, religion, gender, sexual orientation, gender identity, national origin, disability, or any other status protected by applicable law.

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