Senior Golang API Test Engineer

About the Role

This role focuses on validating and strengthening a large-scale, public-facing Fintech API used by institutional clients for trading, custody, and account management workflows. The engineer will work hands-on with an existing End-To-End testing framework, systematically expanding coverage across a broad set of REST endpoints while ensuring correctness, reliability, and consistency. This is a highly independent, execution-driven role within a small senior team, ideal for engineers who enjoy deep API work, structured validation, and operating close to production-grade systems.

Most Important

• Strong Golang engineering experience with production-quality code
• Proven experience in API testing, including REST API validation, integration testing, and End-To-End automation
• Hands-on experience validating authentication, authorization, and permission-based access
• Experience working with JSON schemas, request and response validation, and data integrity checks
• Ability to extend and improve existing test frameworks rather than building from scratch
• Strong debugging and root cause analysis skills across distributed systems
• Eligibility to work remotely from North America, Europe, or Brazil

Nice to Have

• Experience testing financial systems, trading platforms, or high-availability APIs
• Exposure to crypto, digital asset platforms, or exchange-style APIs
• Experience with WebSockets, streaming data, or event-driven systems
• Familiarity with security-sensitive APIs and permission-heavy domains
• Experience working with large API surfaces containing dozens of endpoints

Personal Traits

• Comfortable operating independently with minimal supervision
• Strong attention to detail and methodical execution style
• Clear and structured communication in written and spoken English
• Able to collaborate effectively with senior engineers and engineering managers
• Comfortable reviewing API behavior and providing constructive feedback on design and usability

Our Hiring Process

May change based on various factors (role, profile completeness, etc).

1. ## Initial Interview

Our recruitment team will review your application and contact you if they'd like to proceed with an initial interview. Duration: ~ 1 week

## Skills Assessment

After a successful initial interview, the next step will be an assessment of your technical skills in order to build an 'X-Profile' that we can share with the relevant partner. Duration: ~ 1 week

1. ## Interview with Our Partner

We'll schedule an interview for you to meet our partner, during which you'll get to know more details about the specific role you have been matched with. Duration: ~ 1 week

FAQ

X-Team is committed to providing the ultimate work experience for engineers.

Do you provide paid vacation?

X-Team doesn’t offer paid vacation time, but can arrange for vacation time. We encourage you to incorporate vacation time, health insurance,... into your hourly rate.

Will I be working full-time or part-time hours?

At X-Team we only hire people who can fully dedicate themselves to a project. That means a standard 40 hours per week Monday through Friday.

Do I need to take care of my own taxes?

Yes. Because we hire you as a full-time contractor...