Senior Full Stack Developer – Node.js, React

BillingPlatform

Senior Full Stack Developer building React/Node.js AI Copilot and Agent capabilities. Contributing to BillingPlatform’s cloud-based quote-to-cash revenue lifecycle platform.

Posted 8/19/2026contractRemote • 🇷🇸 SerbiaSeniorWebsite

Core Competencies

Role fit

Core Competencies

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Demonstrates expertise in developing and maintaining React and TypeScript components, building backend services with Node.js and Express, and designing REST APIs. Proficient in AI agent development and familiar with security concepts and testing practices.

Highest-signal resume keywords

Node.js DevelopmentReact Application DevelopmentTypeScript FundamentalsREST API DesignAI Agent Development

ATS Keywords

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Applicant Tracking System Keywords

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Hard Skills

Node.jsExpressReactTypeScriptREST APIsSchema ValidationUnit TestingIntegration TestingAsynchronous JavaScriptDocker

Tools & Technologies

JestOpenAPI/SwaggerAWS BedrockAI Coding AgentsObservability Tooling

Industry Keywords

FintechFinancial SystemsMCP PrinciplesWeb Security ConceptsAI Agent Tooling

Tech Stack

Tools & technologies

AWSCloudDockerJavaScriptJestNode.jsReactTypeScript

About the role

Key responsibilities & impact

Develop and maintain React/TypeScript components
Build and maintain backend services using Node.js, TypeScript, and Express
Design clear, typed contracts for APIs and MCP tools using TypeScript and schema validation
Develop and integrate REST APIs and internal and third-party services
Write and maintain unit and integration tests
Troubleshoot and resolve issues across the application stack
Participate in code reviews and follow internal reuse, security, and testing conventions
Collaborate with backend teams on API contracts, data models, and integration architecture
Use AI coding agents as part of the development workflow
Contribute to the development of AI Copilot and AI Agent capabilities

Requirements

What you’ll need

4+ years of experience with Node.js and Express
2+ years of professional experience with React and TypeScript
Strong TypeScript fundamentals, including generics, utility types, type narrowing, and typed API contracts
Strong understanding of MCP principles
Experience building AI agents
Experience designing and consuming REST APIs
Good understanding of asynchronous JavaScript, Promises, async/await, and error handling
Experience with schema validation libraries such as Zod or similar
Familiarity with Jest, component testing, mocking, and integration testing practices
Understanding of common web security concepts, including CORS, CSRF, input validation, secrets handling, and OWASP fundamentals
Exposure to Model Context Protocol (MCP), AI agent tooling, LLM tool/function calling, or building LLM-facing APIs
Practical experience using AI coding agents such as Codex or Claude Code for code generation, refactoring, testing, and debugging
Experience with AWS Bedrock
Prior experience with fintech or financial systems
Experience working with sensitive customer or financial data
Experience with AWS services and production cloud environments
Docker experience
Experience with OpenAPI/Swagger and API contract documentation
Familiarity with observability tooling, structured logging, metrics, and production debugging
Understanding of API reliability patterns such as retries, timeouts, rate limiting, and idempotency
Experience designing tools or APIs specifically for LLM agents
Experience evaluating or debugging AI-agent workflows and tool calls

Benefits

Comp & perks

Opportunity to contribute to global initiatives and work with an international team
A high-impact role at a growing SaaS company that values personal growth, accountability, and teamwork
Supportive, transparent culture focused on open communication and problem-solving
Company-sponsored English lessons for non-native speakers to support ongoing language development
Fully remote work environment
Competitive pay