Senior Software Engineer

Company Description

Monto is a platform designed for revenue teams to simplify the process of dealing with customer A/P portals. It connects with various payment portals such as Ariba and Coupa, learning each customer's billing requirements. This allows for the management of invoices from a single place, with no manual work involved. Monto aims to make B2B payments seamless by providing connectivity and flexibility, bridging the gap between customer portals and supplier systems.

We are hiring a Senior Fullstack Developer to own complex, high-impact work across backend and frontend. You should be highly proficient in TypeScript end‑to‑end and able to integrate quickly into ongoing initiatives. Beyond technical skill, we value a can‑do mindset, rapid self‑learning, and the ability to blend into a project and make progress with minimal guidance.

• Design and deliver scalable backend services in TypeScript, leveraging serverless and event‑driven patterns on AWS.
• Technologies: Lambda, Step Functions, SES, SQS, SNS, EventBridge, RDS/Aurora (SQL), API Gateway, CloudWatch, Pulumi, SST 
• Build and maintain modern frontend experiences (React preferred), with performance and accessibility in mind.
• Contribute to Infrastructure‑as‑Code (IaC) using SST and Pulumi; developer‑friendly, serverless‑first approach (no heavy DevOps expectations).
• Work with microservices and event‑driven architectures, ensuring clean boundaries and robust integrations.
• Design and implement state machines to model business workflows and handle complex processes.
• Apply Dependency Injection (DI) principles to keep code modular, testable, and maintainable.
• Own features end‑to‑end: from technical design proposals, through implementation and testing, to rollout and post‑release follow‑up.
• Maintain high code quality via tests, reviews, and clean architecture practices.
• Collaborate closely with product/design and other engineers; turn ambiguous requirements into clear, deliverable plans.

Technical

• 8+ years in fullstack development, with advanced TypeScript across backend and frontend.
• Strong experience with AWS (serverless patterns with Lambda, Step Functions, and related services).
• Proficiency with SQL databases (schema design, performance optimization, migrations).
• Practical experience with IaC (especially SST and/or Pulumi).
• Hands‑on experience with microservices and event‑driven architectures. Understanding of state machine concepts and how to apply them in complex workflows.
• Proficiency with Dependency Injection (DI) and clean code design patterns and concepts.
• Solid grasp of system design, reliability, security basics, and scalability trade‑offs.
• Experience serving in a central role within a system operating at scale, demonstrating ability to handle high traffic, complexity, and growth.

Mindset & Collaboration

• Can‑do attitude: proactive, adaptable, and comfortable owning outcomes.
• Fast self‑learner who can blend into an existing codebase and deliver quickly.
• Clear communicator who gives/receives feedback and mentors when needed.

• CI/CD pipeline ownership (e.g., GitHub Actions) and strong automated testing habits.
• Contributions to open source or a demonstrable portfolio.
• Prior leadership experience or driving architecture initiatives.