Charbel Kallas

Software Engineer · Remote

• Designed and developed scalable microservices and REST APIs using JavaScript, TypeScript, and Go, supporting high-traffic applications used by 250K+ organizations worldwide.
• Developed backend capabilities for Password Manager and password policies, implementing security controls, and contributed to Password Vault and Privileged Access capabilities, strengthening identity and access management.
• Designed and optimized distributed systems using Kafka, databases, and caching, with a focus on performance, scalability, reliability, and high availability.
• Developed and maintained cloud-native services within AWS, Docker, and Kubernetes environments, contributing to CI/CD and deployment workflows using Argo CD and Kargo.
• Implemented and maintained observability using Datadog, including monitoring, logging, metrics, and distributed tracing, to support production troubleshooting and incident investigation.
• Participated in system architecture and technical design, code reviews, production on-call, and cross-team initiatives to deliver and maintain reliable services.

• JavaScript
• TypeScript
• Go
• Java
• gRPC
• Kafka
• SQS
• Redis
• PostgreSQL
• MySQL
• MongoDB
• AWS
• EC2
• EKS
• RDS
• Aurora
• DocumentDB
• ElastiCache
• S3
• Docker
• Kubernetes
• Argo CD
• Kargo
• Datadog
• Ginkgo
• Jest
• CI/CD

Java Backend Developer · Beirut, Lebanon

• Designed and developed RESTful and SOAP APIs using Java and Spring Boot, building backend services for digital banking platforms serving 23+ clients, including Al Maryah Bank (UAE).
• Developed and integrated banking and payment services, including ATM withdrawals, money transfers, and third-party APIs, implementing transaction management and authentication/authorization to support secure financial operations.
• Worked with MySQL, Redis, and Kafka to support data management, caching, and asynchronous communication across banking services, contributing to scalable and reliable backend systems.
• Implemented unit and integration testing with JUnit and Mockito, increasing code coverage from 65% to 90%, while troubleshooting production issues and improving system stability and maintainability.

• Java
• Spring Boot
• REST APIs
• SOAP APIs
• MySQL
• Redis
• Kafka
• JUnit
• Mockito
• Microservices

Software Engineer · Beirut, Lebanon

• Developed Java Spring Boot microservices and backend systems for scalable financial applications, building APIs and database operations with PostgreSQL.
• Integrated Hardware Security Modules (HSM) for secure financial transaction processing, including encryption/decryption and PIN processing.
• Implemented Apache Kafka producers and consumers to enable asynchronous communication between backend services and support reliable event-driven workflows.
• Contributed to Verto and VFM (Verto Financial Module), developing APIs and features across card issuing, transaction processing, authorization, limits, and settlement.

• Java
• Spring Boot
• PostgreSQL
• HSM
• Kafka
• Drools
• Teedy
• Microservices

Developer and Application Analyst · Beirut, Lebanon

• Designed and developed ERP, shipping, and membership solutions for business clients, contributing to RHO-SUITE, SHIP-IT, and OASIS platforms and translating business requirements into scalable software solutions.
• Optimized SQL Server databases and backend logic, improving API performance by up to 63% through query optimization while maintaining data integrity through transactional consistency.
• Developed Windows Forms applications using Visual Basic .NET and Infragistics UI, and built Crystal Reports for analytics, reporting, and business operations.

• Visual Basic .NET
• SQL Server
• Crystal Reports
• Infragistics UI