Julius is available for hire

Julius Datoc Pabular

Verified Expert in Engineering

Java Developer

Quezon City, NCR, Philippines

Toptal member since April 17, 2023

Expertise

Back-end Developers Software Development Enterprise Development Web Development Code Review API Full-stack Windows Development Java SQL Agile Development Hibernate Spring Scala Spring Boot

Bio

Julius is an accomplished lead Java developer and engineering manager with expertise in Java back-end development. He has 19+ years of experience delivering innovative and efficient software solutions and a proven ability to design, develop, and maintain robust and scalable software applications in various industries, including finance, banking, healthcare, travel, consulting, and eCommerce. Julius is an expert in coding RESTful APIs and web services, code reviews, mentoring, and agile delivery.

Portfolio

Cheetah Digital

Scala, Hadoop, Big Data, Apache Kafka, Apache Hive, Apache Spark, HBase...

Zühlke Engineering AG

Java, Reactor, MongoDB, AWS Command Line Interface (CLI), Kubernetes, Docker...

Optum

Messaging, JavaScript, jQuery, AngularJS, React, Web Services, REST, Dynatrace...

Experience

Java - 20 years
SQL - 20 years
Agile - 15 years
Back-end Development - 10 years
Spring Boot - 8 years
Microservices - 5 years
Python - 3 years
Scala - 2 years

Work Experience

Lead Software Engineer

2023 - 2024

Cheetah Digital

Coordinated with project management and oversaw the development of various platform enhancements and bug fixes that helped address client issues.
Helped develop point activation enhancements and expiration-related bug fixes to improve operational efficiency for clients and prevent issues related to redemption.
Provided production support for loyalty configuration-related issues. Helped in troubleshooting issues across staging and QA environments for clients that were onboarding to the loyalty platform.

Technologies: Scala, Hadoop, Big Data, Apache Kafka, Apache Hive, Apache Spark, HBase, Snowflake, Amazon S3 (AWS S3), JSON, Trino, Apache Iceberg, Apache Storm, B2C, Functional Programming, Spark, Amazon EC2, Python, Architecture, Code Review, Software Development, Event-driven Architecture, Enterprise, Postman, Documentation, FastAPI, RESTFul APIs, Log Analysis, Stakeholder Management, Caching, Prometheus, Application Performance Monitoring, Data Processing, Team Mentoring, Back-end Architecture, Apache Maven, Cloud, Domain-driven Design (DDD), Version Control, Database Integration, Event Sourcing, RabbitMQ, JDBC, Elastic, Back-end APIs, Mentorship & Coaching, Design Patterns, Engineering Management, Domain-driven Development, Automated Testing, Client-side JavaScript Frameworks, Application Architecture, SSH, Bug Fixes, MongoDB, Artificial Intelligence (AI), Large Language Models (LLMs), Vibe Coding, Cloud Platforms, Spreadsheets, API Design

Expert Software Engineer

2022 - 2023

Zühlke Engineering AG

Developed and maintained RESTful APIs and integrated them with various systems and databases, using technologies such as Spring Boot, MongoDB, AWS, and Kubernetes for an Indonesian healthcare startup.
Applied test-driven development and continuous integration and delivery techniques to ensure quality and stability.
Collaborated with other team members to gather requirements, communicate project progress, and provide technical expertise and guidance.

Technologies: Java, Reactor, MongoDB, AWS Command Line Interface (CLI), Kubernetes, Docker, Messaging, Spring Boot, Amazon Web Services (AWS), Amazon Simple Queue Service (SQS), Amazon Simple Notification Service (SNS), CI/CD Pipelines, MongoDB Shell, MongoDB Atlas, Indexing, Scrum, Jira, Bitbucket, Microservices, NoSQL, Object-oriented Programming (OOP), REST APIs, JSON, Hibernate, SQL, Technical Leadership, Unit Testing, API Development, Containerization, Containers, Technical Consulting, Git, HTML, PostgreSQL, APIs, Databases, Back-end, Java 8, Apache Tomcat, Microservices Architecture, Front-end, JVM, DevOps, Agile, Full-stack, Technical Requirements, Leadership, Software Design, Software Architecture, Amazon S3 (AWS S3), Large-scale Projects, JavaScript, JPA, Team Leadership, OpenAPI, Swagger, JUnit, Gradle, Liquibase, Integration Testing, Back-end Development, Groovy, Java Persistence API (JPA), GitHub, Teams, IntelliJ IDEA, Redis, Concurrent Computing, Startups, B2C, Spring Security, Amazon EC2, Architecture, Code Review, Software Development, Event-driven Architecture, Enterprise, Multithreading, Event-driven Design (EDD), RESTful Microservices, Postman, Documentation, RESTFul APIs, Log Analysis, Payment APIs, Caching, Prometheus, Java Performance Optimization, Full-stack Development, Team Mentoring, Back-end Architecture, Apache Maven, Cloud, Domain-driven Design (DDD), CQRS, Version Control, Database Integration, Event Sourcing, RabbitMQ, JDBC, Back-end APIs, Mentorship & Coaching, Design Patterns, Engineering Management, Domain-driven Development, Automated Testing, Client-side JavaScript Frameworks, Application Architecture, Oracle Database, SQL Stored Procedures, Database Design, Spring Batch, SSH, GraphQL, Neo4j, Artificial Intelligence (AI), Large Language Models (LLMs), Vibe Coding, Cloud Platforms, Web App Development, API Design

Software Engineering Manager

2016 - 2022

Optum

Led multiple teams in developing and delivering high-quality solutions for the healthcare domain, utilizing RESTful API and Java back-end development techniques.
Conducted code reviews, ensuring adherence to coding standards, quality, and performance optimization. Mentored team members to develop their skills and knowledge, enabling them to progress in their careers and contribute effectively to the team.
Helped facilitate the Agile methodology to improve project delivery and team efficiency, resulting in increased productivity and faster time to market.
Collaborated with cross-functional teams, stakeholders, and clients to ensure alignment of project goals with overall business objectives.
Expanded the team's size and capability, recruiting and onboarding new team members and ensuring smooth integration into the team's culture and processes.

Technologies: Messaging, JavaScript, jQuery, AngularJS, React, Web Services, REST, Dynatrace, IBM WebSphere, JBoss EAP, Azure, Docker, Kubernetes, Java, Groovy, Spring Boot, Node.js, TypeScript, Rally, Agile, Azure Cosmos DB, NoSQL, Object-oriented Programming (OOP), REST APIs, JSON, Hibernate, SQL, Technical Leadership, Unit Testing, API Development, Containerization, Containers, Healthcare, Git, HTML, Amazon Web Services (AWS), PostgreSQL, APIs, Databases, Back-end, ETL, Java 8, API Integration, CSV, CSV File Processing, Microservices Architecture, Front-end, JVM, Full-stack, Technical Requirements, HIPAA Compliance, Leadership, Architecture, Software Design, Software Architecture, HIPAA Electronic Data Interchange (EDI), Large-scale Projects, Bootstrap, Thymeleaf, JPA, Team Leadership, GraphQL, OpenAPI, Swagger, JUnit, Gradle, Liquibase, Integration Testing, Back-end Development, Java Persistence API (JPA), GitHub, Teams, IntelliJ IDEA, Redis, Concurrent Computing, B2C, eCommerce, Continuous Integration (CI), Continuous Delivery (CD), Spring Security, Code Review, Software Development, Event-driven Architecture, Enterprise, Multithreading, Event-driven Design (EDD), RESTful Microservices, Healthcare & Insurance, Health Insurance, Postman, Azure API Management, Documentation, ISO 27001, RESTFul APIs, Log Analysis, Stakeholder Management, Payment APIs, Caching, Prometheus, Application Performance Monitoring, Java Performance Optimization, Data Processing, Team Mentoring, Back-end Architecture, Apache Maven, Cloud, Domain-driven Design (DDD), CQRS, Version Control, Database Integration, Event Sourcing, RabbitMQ, JDBC, Elastic, Back-end APIs, Mentorship & Coaching, Design Patterns, Engineering Management, Domain-driven Development, Spring MVC, Automated Testing, Client-side JavaScript Frameworks, Application Architecture, Oracle Database, Azure DevOps, Database Design, Spring Batch, Data Migration, XML, SSH, Bug Fixes, Angular, MongoDB, Microsoft Azure, Next.js, Cloud Platforms, Spreadsheets, Web App Development, API Design

Java Developer | Team Lead

2016 - 2016

2Success Inc

Drove the development efforts for the back-office system and coordinated with various stakeholders for requirement gathering and project deliverables.
Drove the team to adopt Agile practices in developing enhancements and fixing defects.
Guided and mentored junior developers. Performed code reviews to ensure high-quality code.

Technologies: Java, Google Guice, jQuery, Ext JS, MyBatis, Object-oriented Programming (OOP), REST APIs, JSON, SQL, Technical Leadership, Unit Testing, API Development, Web Scraping, Jira, Back-end, Apache Tomcat, JVM, Agile, Full-stack, Technical Requirements, Leadership, Software Architecture, Team Leadership, JUnit, Back-end Development, IntelliJ IDEA, Startups, B2C, Code Review, Software Development, Documentation, RESTFul APIs, Stakeholder Management, Payment APIs, Caching, Team Mentoring, Back-end Architecture, Apache Maven, Version Control, Database Integration, JDBC, Back-end APIs, Mentorship & Coaching, Design Patterns, Engineering Management, Software Development Lifecycle (SDLC), Spring MVC, Oracle Database, Database Design, Spring Batch, Bug Fixes, Spreadsheets, Web App Development

Senior Developer

2016 - 2016

Hyphen Group

Helped develop new features for the Country In a Box initiative.
Handled the release management activities for an internal project, the Libris platform.
Collaborated with team members to gather requirements, communicate project progress, and provide technical expertise and guidance.

Technologies: Java, Amazon Web Services (AWS), Mule ESB, REST, PHP 5, Backbone.Marionette, Node.js, Spring Boot, Object-oriented Programming (OOP), REST APIs, JSON, Hibernate, SQL, Fintech, Unit Testing, API Development, Jira, Back-end, JVM, JUnit, Back-end Development, IntelliJ IDEA, Startups, Software Development, Documentation, RESTFul APIs, Caching, Team Mentoring, Apache Maven, Version Control, Database Integration, JDBC, Apache Struts, Back-end APIs, Design Patterns, Spring MVC, Java EE (Jakarta EE), Data Migration, Web App Development

Senior Software Engineer

2012 - 2016

DTCC

Analyzed and resolved critical failures and defects that affected a global client base, ensuring their revenue from settling trades was not disrupted.
Collaborated with clients in major investment management and brokerage firms to help stabilize their post-trade process throughput in case of system slowdowns.
Conducted performance reviews, mentored the team members, and helped them make their career progression plans.

Technologies: Java, XML, Oracle, Unix, Regex, Shell Scripting, Kanban, SQL, Object-oriented Programming (OOP), Fintech, Unit Testing, API Development, Back-end, Apache Tomcat, JVM, Java Servlets, JUnit, Back-end Development, Big Data, Software Development, Multithreading, Documentation, Java Performance Optimization, Data Processing, Team Mentoring, Version Control, Database Integration, FIX Protocol, Finance, Trading, Low-latency Software, Jakarta Server Pages (JSP), JDBC, Java EE 8, Apache Struts, Back-end APIs, Design Patterns, Software Development Lifecycle (SDLC), Java EE (Jakarta EE), SQL Stored Procedures, SSH, Support, Financial Data

Project History

Web Application for Pharmacy Benefit Management

I led multiple teams to maintain a web application built with Adobe Experience Manager, Angular, React, Java, and Spring for managing pharmacy benefits in the US. I was one of the primary contributors to the back-end code, developing new features and fixing bugs while ensuring quality and compliance with coding standards. Through my contributions, the platform reached the goal of achieving 80% order completion by resolving critical bugs that affected the user experience.

Tellering System for a Local Bank

A React and Java application created as part of a local bank's digital transformation efforts to modernize their client-facing applications and I was part of the back-end development team that built RESTful APIs serving processes such as retail/corporate client onboarding, cash, cheque, bill payment, and miscellaneous transactions.

Web Application for Order Tracking of Pharmacy Benefits

A React and Java Spring Boot Microservices application that lets members track their order without logging in to the member portal. I was the lead developer working on the microservices that backed the order-tracking UI built in React. Also, I acted as the overall technical lead of the project, handling both back-end and front-end developers.

SEO Performance Management for Marketing Organization

Helped build parts of an SEO platform that ingested data from streaming sources and Google Search Console (for client websites) and ran an analysis to check if improvements like link/content generation helped improve SEO performance.

Beverage Manufacturer Scheme Expansion

A web application built with React and Java for beverage manufacturer onboarding expansion scheme. I was responsible for writing the back-end microservices that handled the management of beverage manufacturer registrations and integration with a 3rd-party contract management system.

Saas Platform for Actuarial Services

A web-based SaaS platform written in Svelte and Spring Boot for actuarial services. I developed new features for the platform, including new functionality for recipient account management and approval workflow. I tracked and fixed bugs that improved the performance of key business processes for payment generation and worked on end-to-end functionality, including UI, REST API endpoints, and SQL stored procedures.

Facility Management API PowerApp Integration

RESTful API written in Python (FastAPI) that integrates a job management app developed in PowerApps with a facility management external platform. This integration streamlines system communication by enabling seamless data exchange, improving task automation, and enhancing operational efficiency. Designed to optimize workflows, it facilitates improved coordination between job scheduling and facility management processes.

AI-powered RPA Workflow Platform

A full-stack web application built with React (front end) and Python (Django back end) that intelligently identifies bottlenecks and inefficiencies in user-defined workflows. By analyzing structured inputs—such as task sequences, durations, dependencies, and resource allocations - the app generates actionable suggestions to streamline operations, reduce latency, and boost throughput.

Back-end Modernization to Microservices Architecture

Led a team of back-end and front-end engineers with the migration of a legacy back end from a monolith to an async, event-driven microservices architecture using Java, Spring Boot, Azure, and PostgreSQL, designing and implementing resilient services and integrations across multiple domains.

IP Docketing System

Contributed to the backend development of an intellectual property (IP) docketing system using Java, Spring Boot, MongoDB, and Spring Data. Helped implement backend functionality and data management to support IP records and associated workflows. Used Claude Code as an AI-assisted development tool while working on the backend codebase. Collaborated on translating requirements into maintainable code within the existing application architecture.

Education

2002 - 2004

Bachelor's Degree in Computer Science

Informatics International College - Manila, Philippines

1999 - 2002

Bachelor's Degree in Computer Science

University of Santo Tomas - Manila, Philippines

Certifications

APRIL 2019 - APRIL 2020

Certified SAFe 4 Agilist

Scaled Agile Inc.

FEBRUARY 2018 - PRESENT

Professional Scrum Master I (PSM I)

Scrum.org

NOVEMBER 2006 - PRESENT

Sun Certified Programmer, Java 1.4

Sun Microsystems

JUNE 2005 - PRESENT

Sun Certified Associate, Java 1.4

Sun Microsystems

Skills

Libraries/APIs

React, Node.js, REST APIs, API Development, OpenAPI, Java Servlets, Liquibase, JDBC, Back-end APIs, Azure API Management, NumPy, Pandas, Pydantic, jQuery, Reactor, Backbone.Marionette, MyBatis, Vue

Tools

IntelliJ IDEA, GitHub, Git, Flyway, Postman, Apache Maven, Claude Code, Slack, Gradle, Apache Tomcat, Pytest, Elastic, SendGrid, BigQuery, Spreadsheets, Dynatrace, AWS Command Line Interface (CLI), Adobe Experience Manager (AEM), Amazon Simple Queue Service (SQS), Amazon Simple Notification Service (SNS), MapStruct, Google Compute Engine (GCE), Google Kubernetes Engine (GKE), MongoDB Shell, MongoDB Atlas, Jira, Bitbucket, Rally, Apache Iceberg, Apache Storm, Microsoft Power Apps, RabbitMQ

Languages

Java, JavaScript, Groovy, XML, SQL, TypeScript, Python, Scala, Java 8, GraphQL, Snowflake, Java EE 8, C, C++, Visual Basic, PHP 5, Regex, R, CSS, HTML

Frameworks

Hibernate, Spring, Spring Boot, JPA, Java Persistence API (JPA), Swagger, JUnit, Jakarta Server Pages (JSP), Scaled Agile Framework (SAFe), Angular, Spring Microservice, Spark, Spring Security, Svelte, Apache Struts, Spring MVC, Django, Spring Batch, Next.js, Flask, AngularJS, Google Guice, Ext JS, Hadoop, Bootstrap, Thymeleaf, Apache Spark, Trino

Paradigms

Microservices, Agile, Object-oriented Programming (OOP), Unit Testing, Back-end Architecture, Design Patterns, Domain-driven Development, Database Design, Model Context Protocol (MCP), REST, Scrum, Microservices Architecture, HIPAA Compliance, B2C, Functional Programming, Continuous Integration (CI), Continuous Delivery (CD), Event-driven Architecture, Event-driven Design (EDD), Java Performance Optimization, CQRS, Event Sourcing, Automated Testing, Application Architecture, Azure DevOps, Compiler Design, Kanban, ETL, DevOps

Platforms

Windows, Amazon Web Services (AWS), JVM, Java EE (Jakarta EE), MacOS, Docker, Unix, Linux, Kubernetes, Oracle, Google Cloud Platform (GCP), Cloud Run, Amazon EC2, Oracle Database, IBM WebSphere, JBoss EAP, Azure, Mule ESB, Apache Kafka, Microsoft Power Platform

Storage

MongoDB, PostgreSQL, JSON, SQL Stored Procedures, MySQL, Google Cloud, NoSQL, Databases, SQL Server 2016, Amazon S3 (AWS S3), Redis, Google Bucket, Database Integration, Neo4j, Azure Cosmos DB, Apache Hive, HBase, Spring Data

Industry Expertise

Healthcare

Other

Technical Leadership, APIs, Back-end, API Integration, Full-stack, Technical Requirements, Leadership, Architecture, Software Design, Software Architecture, Team Leadership, Back-end Development, Code Review, Software Development, Enterprise, RESTful Microservices, Reporting, FastAPI, RESTFul APIs, Log Analysis, Caching, Team Mentoring, Version Control, Mentorship & Coaching, Engineering Management, Software Development Lifecycle (SDLC), Bug Fixes, Support, Financial Data, Web App Development, API Design, AI-generated Code, Web Services, Fintech, Containerization, Containers, Technical Consulting, API Testing, Web Scraping, Data Engineering, Profiling, CSV, CSV File Processing, HIPAA Electronic Data Interchange (EDI), Large-scale Projects, Integration Testing, Big Data, Concurrent Computing, Startups, eCommerce, Multithreading, Healthcare & Insurance, Health Insurance, Documentation, ISO 27001, Stakeholder Management, Payment APIs, Prometheus, Application Performance Monitoring, Data Processing, Full-stack Development, Cloud, Domain-driven Design (DDD), FIX Protocol, Finance, Trading, Low-latency Software, Client-side JavaScript Frameworks, Data Migration, SSH, Artificial Intelligence (AI), Large Language Models (LLMs), Vibe Coding, Microsoft Azure, Cloud Platforms, Office 365, Messaging, Teams, Discord, Systems Analysis, Operating Systems, Shell Scripting, CI/CD Pipelines, Project Lombok, Google Cloud Build, Indexing, Google BigQuery, Front-end, Parquet, Data Build Tool (dbt)

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Work Experience

Lead Software Engineer

2023 - 2024

Cheetah Digital

Coordinated with project management and oversaw the development of various platform enhancements and bug fixes that helped address client issues.
Helped develop point activation enhancements and expiration-related bug fixes to improve operational efficiency for clients and prevent issues related to redemption.
Provided production support for loyalty configuration-related issues. Helped in troubleshooting issues across staging and QA environments for clients that were onboarding to the loyalty platform.

Expert Software Engineer

2022 - 2023

Zühlke Engineering AG

Developed and maintained RESTful APIs and integrated them with various systems and databases, using technologies such as Spring Boot, MongoDB, AWS, and Kubernetes for an Indonesian healthcare startup.
Applied test-driven development and continuous integration and delivery techniques to ensure quality and stability.
Collaborated with other team members to gather requirements, communicate project progress, and provide technical expertise and guidance.

Software Engineering Manager

2016 - 2022

Optum

Led multiple teams in developing and delivering high-quality solutions for the healthcare domain, utilizing RESTful API and Java back-end development techniques.
Conducted code reviews, ensuring adherence to coding standards, quality, and performance optimization. Mentored team members to develop their skills and knowledge, enabling them to progress in their careers and contribute effectively to the team.
Helped facilitate the Agile methodology to improve project delivery and team efficiency, resulting in increased productivity and faster time to market.
Collaborated with cross-functional teams, stakeholders, and clients to ensure alignment of project goals with overall business objectives.
Expanded the team's size and capability, recruiting and onboarding new team members and ensuring smooth integration into the team's culture and processes.

Java Developer | Team Lead

2016 - 2016

2Success Inc

Drove the development efforts for the back-office system and coordinated with various stakeholders for requirement gathering and project deliverables.
Drove the team to adopt Agile practices in developing enhancements and fixing defects.
Guided and mentored junior developers. Performed code reviews to ensure high-quality code.

Senior Developer

2016 - 2016

Hyphen Group

Helped develop new features for the Country In a Box initiative.
Handled the release management activities for an internal project, the Libris platform.
Collaborated with team members to gather requirements, communicate project progress, and provide technical expertise and guidance.

Senior Software Engineer

2012 - 2016

DTCC

Analyzed and resolved critical failures and defects that affected a global client base, ensuring their revenue from settling trades was not disrupted.
Collaborated with clients in major investment management and brokerage firms to help stabilize their post-trade process throughput in case of system slowdowns.
Conducted performance reviews, mentored the team members, and helped them make their career progression plans.

Project History

Web Application for Pharmacy Benefit Management

Tellering System for a Local Bank

Web Application for Order Tracking of Pharmacy Benefits

SEO Performance Management for Marketing Organization

Beverage Manufacturer Scheme Expansion

Saas Platform for Actuarial Services

Facility Management API PowerApp Integration

AI-powered RPA Workflow Platform

Back-end Modernization to Microservices Architecture

IP Docketing System

Education

2002 - 2004

Bachelor's Degree in Computer Science

Informatics International College - Manila, Philippines

1999 - 2002

Bachelor's Degree in Computer Science

University of Santo Tomas - Manila, Philippines

Certifications

APRIL 2019 - APRIL 2020

Certified SAFe 4 Agilist

Scaled Agile Inc.

FEBRUARY 2018 - PRESENT

Professional Scrum Master I (PSM I)

Scrum.org

NOVEMBER 2006 - PRESENT

Sun Certified Programmer, Java 1.4

Sun Microsystems

JUNE 2005 - PRESENT

Sun Certified Associate, Java 1.4

Sun Microsystems

Skills

Libraries/APIs

React, Node.js, REST APIs, API Development, OpenAPI, Java Servlets, Liquibase, JDBC, Back-end APIs, Azure API Management, NumPy, Pandas, Pydantic, jQuery, Reactor, Backbone.Marionette, MyBatis, Vue

Tools

Languages

Java, JavaScript, Groovy, XML, SQL, TypeScript, Python, Scala, Java 8, GraphQL, Snowflake, Java EE 8, C, C++, Visual Basic, PHP 5, Regex, R, CSS, HTML