Software Engineer II - Backend

Wati is a growing SaaS platform that provides end-to-end WhatsApp API solutions for SMBs and large enterprises. We aim to simplify business communication, helping businesses meet their customers where they are - WhatsApp, Instagram, Messenger, and etc.

Backed by global investors such as Sequoia, DST Global, and Tiger Global, we're Shopify's first investment in a startup in Asia.

Headquartered in Hong Kong and trusted by 12000+ customers across 100+ countries. We're a rapidly expanding team filled with talented people from around the globe.

We are growing fast, and we are now looking for a Software Engineer II - Backend to work closely with Development, QA, DevOps, Support and Product. You are a leader that will participate in senior technology strategy discussions, drive ideation across a distributed software team, develop implementation roadmaps and work with technical individuals to transform this into software products and solutions.

What you’ll do: 

• Refactor, test, and maintain components of our monolithic C# application, gradually migrating critical services to Golang microservices with clean, reusable, and efficient code.
• Design, develop, and deploy high-traffic distributed systems (e.g., REST/gRPC APIs, event-driven workflows, data pipelines) using Go and C#, ensuring fault tolerance and resilience.
• Improve latency, throughput, and resource efficiency in both legacy C# and modern Go services, leveraging caching (Redis), message brokers (Kafka/RabbitMQ), and database optimization.
• Collaborate with cross-functional teams, including design, product, and QA, to deliver a seamless and engaging user experience.
• Partner with DevOps to streamline CI/CD pipelines, QA to automate testing, and Product to align technical solutions with business requirements.
• Participate in system design reviews, advocate for scalable patterns (e.g., circuit breakers, load balancing), and ensure security best practices (auth, RBAC, encryption).
• Troubleshoot and resolve backend performance, scalability, and reliability challenges in production environments.
• Lead code reviews, mentor junior engineers, and champion standards for maintainable code across C# and Go codebases

• Bachelor’s degree in Computer Science, Engineering, or related field, or equivalent practical experience.
• 5+ years of backend development experience, including:
• 2+ years with C# (.NET Core, ASP.NET, Entity Framework) in monolithic architectures. OR
• 1+ years with Golang (Gin, Echo, Goroutines, Go modules) or strong willingness to learn.
• Expertise in distributed systems: REST/gRPC APIs, microservices, message brokers (Kafka/RabbitMQ), and caching (Redis).
• Proficiency in database design and optimization (SQL: PostgreSQL/MySQL; NoSQL: MongoDB).
• Hands-on experience with cloud platforms (AWS/Azure/GCP), containerization (Docker/Kubernetes), and CI/CD pipelines (GitHub Actions/Jenkins).
• Strong understanding of security practices: authentication/authorization (JWT, OAuth), RBAC, and data encryption.
• Fluency in English with excellent communication skills to collaborate across global teams.

What will make you stand out: 

• Hands-on experience coding with tools like GitHub Copilot, Cursor, or other AI-assisted development environments.
• Proven track record of building and launching products from 0 to 1.
• Prior experience developing overseas or export-focused applications.
• Experience with serverless architectures (e.g., AWS Lambda) or microservices architectures.
• Knowledge of event-driven systems (e.g., Kafka, RabbitMQ).
• Prior work on scalable, high-traffic applications.