Publication
7 Debugging Techniques To Speed Up Troubleshooting in Production
https://www.toptal.com/developers/qa/7-debugging-techniques-prod
Flavio is currently unavailable
Flavio Pezzini
Verified Expert in Engineering
Java Developer
Blumenau - State of Santa Catarina, Brazil
Toptal member since July 17, 2017
Bio
Flavio is a results-driven senior Java/Rust developer with over 20 years of experience delivering complex/distributed projects for a variety of clients and industries (growthday.com, Dell, Deutsche Bank, PLS Logistics, Optiva Telecom). He's fluent in English, Portuguese, Spanish, and Italian. His passion lies in improving software and simplifying complex architectures. Flavio also enjoys building intuitive user interfaces that are a joy to use. He's a dual Italian/Brazilian citizen.
Portfolio
Kepler Cheuvreux SA
Java, Spring Boot, Apache Kafka, REST APIs, Amazon Web Services (AWS), Trading...
PLS Logistics
Java, Angular, Spring, Hibernate, JavaScript, CI/CD Pipelines, Containerization...
flexEngage
Kotlin, Linux, Java, Spring, Spring REST, Spring Data, Docker, Kubernetes, Git...
Experience
- Java - 20 years
- Spring Boot - 13 years
- Git - 10 years
- Software Architecture - 9 years
- Docker - 4 years
- Rust - 2 years
- Kotlin - 1 year
- Angular - 1 year
Preferred Environment
IntelliJ IDEA, Git
The most amazing...
...project I’ve worked on was developing and maintaining six applications with millions of lines of code and extremely complex telecom business transactions.
Work Experience
Senior Back-end Developer
2025 - 2025
Kepler Cheuvreux SA
- Created an ETF trading that saves the company millions of euros per year by simplifying and speeding up the process.
- Simplified and synthesized many very ambiguous and shallow requirements for a highly complex and distributed project in high-frequency trading.
- Worked tirelessly to improve the application's performance to achieve the sub-50-microsecond budget for the whole transaction.
Technologies: Java, Spring Boot, Apache Kafka, REST APIs, Amazon Web Services (AWS), Trading, Agrona, FIX Protocol, Hydra, Full-stack Development, Python, Distributed Software, Asynchronous Data Streams, Caching, Messaging, Data Marshalling, Microservices, Event-driven Architecture, Event-driven Design (EDD), Back-end, APIs, Data Security, API Integration, Architecture, Distributed Systems, High-frequency Trading (HFT), Metrics, Performance Optimization, HTML, JVM, Software Architecture, Code Review, Back-end Development, Cloud Architecture, Code Deployment, API Development, Authentication, Debugging, Test-driven Development (TDD), Team Leadership, Message Queues, Solution Architecture, Real-time Systems, Data Modeling, Scalability, Access Control, Relational Databases, Claude, Object-oriented Programming (OOP), Java SE (Core Java), Microservices Architecture, Unit Testing, Continuous Delivery (CD), Continuous Integration (CI), Enterprise Architecture, Cloud, WebSockets, Algorithms, JSON, Automation, Refactoring, Code Auditing, Low-latency Software, Real-time Data, Reporting, System Design, Security, Application Architecture, NoSQL, Efficient Data Serialization, Fintech, Kafka Connect, DevOps, Automated Trading Software, Logging, Trading Systems, Event-driven Systems, Software, Software Development, Docker Compose, Technical Documentation, Database Architecture, Technical Leadership, Back-end Architecture, Enterprise Systems, Troubleshooting, Documentation, SDKs, Large-scale Projects, Software Engineering
Full-stack Developer
2022 - 2024
PLS Logistics
- Built improvements to the software managing a document approval workflow that reduced the average time to approve a document from 6.5 days to 1.8 days, which also sped up the time to pay carriers.
- Allowed the customer to reduce the team performing these document verifications from 25 to 6, thereby saving the company millions of dollars.
- Applied software techniques and algorithms to automate this validation workflow entirely (no human touch), reaching 26% of full automation.
- Ran Selenium to open specific whitelisted URLs to download PDF files.
- Applied security best practices, including moving credentials from the source code into Google Cloud Secret Manager.
- Used a policy of zero production error logs, where I proactively watched the production logs and fixed any issues that would appear as quickly as possible.
- Used PMD (static analysis) integrated into the Jenkins build process to ensure the code was only deployed if it was clean of known bugs or software malpractices.
Technologies: Java, Angular, Spring, Hibernate, JavaScript, CI/CD Pipelines, Containerization, AngularJS, Selenium, Pub/Sub, Jenkins, Kubernetes, Google Cloud, Jenkins Pipeline, Graph API, PostgreSQL, Full-stack Development, Python, Spring Data JPA, Google Cloud SDK, Microservices, Event-driven Architecture, Event-driven Design (EDD), JSON Web Tokens (JWT), Back-end, JUnit, TypeScript, APIs, Data Security, User Interface (UI), Front-end, User Experience (UX), REST APIs, API Integration, Architecture, Distributed Systems, Metrics, Performance Optimization, HTML, JVM, Software Architecture, Code Review, Springbot, Google Cloud Platform (GCP), Back-end Development, Front-end Development, Cloud Architecture, Code Deployment, API Development, Authentication, Single Sign-on (SSO), Debugging, Document Processing, Workflow Automation, Test-driven Development (TDD), Full-stack, Team Leadership, Message Queues, Solution Architecture, Real-time Systems, Data Modeling, Scalability, Access Control, Relational Databases, Claude, Cursor AI, Object-oriented Programming (OOP), Java SE (Core Java), Microservices Architecture, Unit Testing, Continuous Delivery (CD), Continuous Integration (CI), Azure, Enterprise Architecture, Cloud, WebSockets, Algorithms, JSON, Automation, Database Migration, Refactoring, Code Auditing, Real-time Data, Reporting, System Design, Security, Application Architecture, NoSQL, Server-side Rendering (SSR), Redis Pub/Sub, Redis Streams, NGINX, AWS Secrets Manager, DevOps, GCP DevOps, Logging, Event-driven Systems, Software, Software Development, Docker Compose, Technical Documentation, Database Architecture, Technical Leadership, Back-end Architecture, Enterprise Systems, Troubleshooting, Documentation, SDKs, PDF, Large-scale Projects, Software Engineering
Senior Java Developer
2022 - 2022
flexEngage
- Wrote a data pipeline that utilizes Kotlin, Amazon Simple Notification Service (SNS), and Amazon Simple Queue Service (SQS) to fetch specific statistics out of a list of customer transactions.
- Contributed to this pipeline that is designed to handle large amounts of data and is built using a combination of asynchronous messaging and event-driven architecture.
- Investigated and solved several issues blocking the existing legacy application from running within Docker on an M1 MacBook.
Technologies: Kotlin, Linux, Java, Spring, Spring REST, Spring Data, Docker, Kubernetes, Git, Full-stack Development, Spring Data JPA, Distributed Software, Asynchronous Data Streams, Bash Script, Minikube, Messaging, Amazon Simple Notification Service (SNS), Amazon Simple Queue Service (SQS), Microservices, Event-driven Architecture, Event-driven Design (EDD), JSON Web Tokens (JWT), Back-end, JUnit, APIs, Data Security, REST APIs, API Integration, Architecture, Distributed Systems, Metrics, Performance Optimization, HTML, JVM, Software Architecture, Code Review, Springbot, Back-end Development, Cloud Architecture, Code Deployment, API Development, Authentication, Debugging, Webhooks, Test-driven Development (TDD), Full-stack, Team Leadership, Message Queues, Solution Architecture, Data Modeling, Scalability, Access Control, Relational Databases, Object-oriented Programming (OOP), Java SE (Core Java), Microservices Architecture, Unit Testing, Continuous Delivery (CD), Continuous Integration (CI), Enterprise Architecture, Cloud, WebSockets, Software as a Service (SaaS), Algorithms, JSON, Database Migration, Refactoring, Code Auditing, Low-latency Software, Real-time Data, Reporting, System Design, Application Architecture, DevOps, Logging, Event-driven Systems, Software, Software Development, Docker Compose, Technical Documentation, Database Architecture, Technical Leadership, Back-end Architecture, Enterprise Systems, Troubleshooting, Documentation, SDKs, Large-scale Projects, Software Engineering
Java Architect
2021 - 2022
GrowthDay
- Improved the application's security by identifying gaps in the infrastructure setup.
- Added code validations following the ideas from secure by design to ensure the security of the data from the application.
- Extracted a microservice to handle all the notifications sent through OneSignal to offload the main server.
- Created features with high-quality software using test-driven development (TDD) and SOLID Principles in a fast-paced environment.
Technologies: Java, Spring, MongoDB, Amazon Web Services (AWS), Amazon Simple Queue Service (SQS), JUnit, Mockito, Apache Maven, API Design, REST, Linux, Kotlin, JSON, Software Architecture, Jackson, Spring REST, Redis, Full-stack Development, Microservices, Event-driven Design (EDD), JSON Web Tokens (JWT), Back-end, TypeScript, APIs, User Interface (UI), Front-end, User Experience (UX), REST APIs, API Integration, Architecture, Distributed Systems, Metrics, Performance Optimization, HTML, JVM, Code Review, Springbot, Back-end Development, Front-end Development, Code Deployment, API Development, Authentication, Single Sign-on (SSO), Debugging, Webhooks, Document Processing, Test-driven Development (TDD), Full-stack, Team Leadership, Solution Architecture, Scalability, Access Control, Non-relational Databases, Relational Databases, Object-oriented Programming (OOP), Java SE (Core Java), Microservices Architecture, Unit Testing, Continuous Delivery (CD), Continuous Integration (CI), Enterprise Architecture, Cloud, WebSockets, Algorithms, Database Migration, Refactoring, Firebase, Real-time Data, Reporting, System Design, Security, Application Architecture, NoSQL, Payment Gateways, Stripe API, Stripe, Logging, Event-driven Systems, Software, Software Development, Docker Compose, Technical Documentation, Database Architecture, Technical Leadership, Back-end Architecture, Enterprise Systems, Troubleshooting, Documentation, SDKs, Amazon EC2, Amazon S3 (AWS S3), Large-scale Projects, Software Engineering
Java Architect
2020 - 2021
Superior Consulting Services - Ralf Lüttgen
- Created a REST service to use an existing list of back-end beans that stored information about a telecom company infrastructure. Added integration tests using REST Assured.
- Developed migration services to pull data from legacy systems and transform them before storing them in the new system.
- Created a SOAP service to use an existing list of back-end beans that stored information about the company infrastructure and added integration tests using SoapUI.
Technologies: Git, SoapUI, SOAP, Oracle, Java Message Service (JMS), JPA, Hibernate, Java, SQL, Jackson, Full-stack Development, Microservices, Back-end, JUnit, REST APIs, Architecture, Performance Optimization, HTML, Software Architecture, Code Review, Springbot, Back-end Development, Front-end Development, Code Deployment, API Development, Authentication, Debugging, Test-driven Development (TDD), Full-stack, Team Leadership, Relational Databases, Object-oriented Programming (OOP), Java SE (Core Java), Web Services Description Language (WSDL), Microservices Architecture, Unit Testing, Enterprise Architecture, Cloud, Algorithms, JSON, Database Migration, Refactoring, Reporting, System Design, Application Architecture, Software, Software Development, Technical Leadership, Back-end Architecture, Enterprise Systems, Troubleshooting, Documentation, Large-scale Projects, Software Engineering
Java Architect
2020 - 2020
IMFyi
- Recovered the source code from a WAR file (decompiler), added back all the Java generics lost during compilation, figured out all the necessary dependencies, and generated a proper pom.xml file with all of the correct versions.
- Fixed a nasty concurrency issue in production that was causing timeouts and essentially crashing the site every 15 minutes. This put the site back in business and enabled them to serve more clients simultaneously.
- Solved massive performance issues with pagination in specific pages on the UI—pages that took 8-10 seconds to load started loading instantaneously.
- Generated a list of recommendations and architectural plans to move the application to a more modern platform.
- Set up the application locally and generated a comprehensive guide for future developers on setting up their environments.
Technologies: Git, Jira, PostgreSQL, Java Message Service (JMS), Java EE (Jakarta EE), JBoss, Full-stack Development, Microservices, Back-end, JUnit, REST APIs, Architecture, Performance Optimization, HTML, Software Architecture, Code Review, Front-end Development, Team Leadership, Relational Databases, Object-oriented Programming (OOP), Unit Testing, Enterprise Architecture, Algorithms, JSON, Refactoring, System Design, Enterprise Systems, Software Engineering
Senior Java Developer
2019 - 2020
Tremor
- Developed features to add to the auctioning platform.
- Hunted down and patched bugs by creating the necessary unit tests to demonstrate the bug's existence and then fixing them.
- Refactored portions of the code to be safer, more performant, and more precise, following the industry-wide guidelines and recommendations from SonarQube.
- Created a layer of abstraction on top of AWS services so that it would be possible to test the application locally without hitting AWS quotas when testing portions of the system that did not require AWS.
Technologies: JOOQ, Git, PostgreSQL, Spring Security, Spring Boot, Microservices, Back-end, JUnit, REST APIs, Architecture, HTML, Software Architecture, Code Review, Team Leadership, Relational Databases, Object-oriented Programming (OOP), Unit Testing, Enterprise Architecture, JSON, System Design, Role-based Access Control (RBAC), Software Engineering
Senior Java Developer
2018 - 2018
Ernst & Young
- Contributed to a three-month-long project to provide secure storage of files for client applications.
- Implemented Spring Security to authenticate users via SSO and basic authentication.
- Stored the file metadata using Spring Data, initially transitioning to MySQL and then moving to PostgreSQL.
- Refactored the source code to bring it up to standards.
- Implemented new endpoints and made adjustments to existing REST endpoints.
- Tested using both unit tests and JMeter for performance assessment.
Technologies: Spring Boot, Spring Data, PostgreSQL, Spring Security, Docker, Java, Back-end, JUnit, REST APIs, Architecture, Performance Optimization, Code Review, Object-oriented Programming (OOP), Unit Testing, Software Engineering
Chief Java Architect
2017 - 2018
Optiva
- Troubleshot and fixed the most difficult issues assigned to the team.
- Designed and implemented code changes to the applications following the latest code-quality recommendations.
- Built a root cause analysis for production crashes and slowness issues, including heap dump, garbage collector logs, thread dump, log analysis, and VM tuning.
- Created solution architectures, algorithms, and designs for solutions that scale to the customer's enterprise and their global requirements.
- Developed my expertise in one or more of the customer's proprietary enterprise software products.
Technologies: SoapUI, SOAP, Apache Kafka, ActiveMQ, Git, Web Services, Java, Back-end, JUnit, REST APIs, Architecture, Performance Optimization, RabbitMQ, Multi-tenant SaaS, Multi-tenant Architecture, Scalability, Web Services Description Language (WSDL), Unit Testing, Software as a Service (SaaS), Low-latency Software, Real-time Data
Senior Java Developer
2014 - 2017
PrestoSports
- Built a Java web system responsible for collecting data about collegiate sports teams in the US and Canada.
- Developed new features such as a user interface to allow users to automatically watch sports seasons into the next year.
- Addressed existing bugs, not merely fixing the bug itself but finding the root cause and applying the definitive fix.
- Fixed critical production issues by identifying the root cause and creating plans to avoid the problem in the future.
- Contributed to peer reviews and solution-brainstorming meetings for my team and other teams as well.
- Refactored code to address new needs; for instance, an overhaul of several system modules to upgrade the TinyMCE framework to the latest version. This included processing and sanitizing embedded videos (both hosted and from YouTube).
Technologies: Git, Jira, Apache Velocity, HTML5, CSS, MySQL, Hibernate, JSTL, Spring, Java, Jakarta Server Pages (JSP), Unit Testing, Server-side Rendering (SSR), IT Project Management, Project Management
Java Support Engineer
2013 - 2014
IBM
- Created usage and health reports based on various log files using shell scripts and Java for a large (20,000+ users) project-management system.
- Monitored system health by checking RAM, CPU, and disk usage.
- Took part in the deployment processes executing all the Linux and database steps and ensuring that the other professionals did their part on time according to the overall plan.
- Offered system health and production feedback to the main development team so that they could improve the application.
Technologies: Shell Scripting, Java, Unit Testing, Server-side Rendering (SSR)
Senior Java Developer | Team Leader
2012 - 2013
Freelance
- Developed Java back-end systems for the Malaysian government responsible for providing various permits.
- Recruited professionals to complete various website-building projects.
- Managed professionals related to project website building, including features to a website, a whole website redesign, translations, and more.
- Developed an onboarding wizard that allowed a company to record information and images of new customers into their system.
- Conducted peer code reviews of junior colleagues providing detailed feedback.
Technologies: CSS, HTML5, JavaScript, Java, Server-side Rendering (SSR)
Project Manager
2011 - 2011
LATAM Airlines Group
- Managed TAM's (the largest Brazilian airline) back-end systems in the travel industry. These systems are connected to Amadeus (one of the largest tourism software companies) and other 3rd-party systems.
- Ensured the projects were delivered on time and were feature-complete.
- Communicated with all the teams at TAM, Amadeus, and 3rd-party contractors.
- Produced project plans and updated them accordingly.
- Provided daily status reports to the upper management.
Technologies: Leadership, IT Project Management, Project Management
Project Manager
2010 - 2011
CPMBraxis (via Bradesco Bank)
- Managed a team of 15 analysts and developers working on six projects using Java and mainframe (COBOL) technologies for the banking industry.
- Interviewed candidates for the various positions available.
- Updated MS Project files according to the latest changes in the project execution.
- Took part in requirements gathering and clarification meetings.
- Mentored professionals towards improving their careers.
- Acted as a mediator during conflicts, looking to find a compromise between the various stakeholders.
Technologies: Java, COBOL, IT Project Management, Project Management
Support Analyst Level 2
2009 - 2010
Dell
- Led and managed bridge conferences towards a quick resolution of high severity issues–such as when Dell.com's website went down. It was about recruiting to the call all the necessary human resources and drive the issue to resolution.
- Updated the documentation and executed a root cause analysis afterward.
- Drove the resolution of lower severity issues, including being the point of contact between business areas and the development teams–taking full responsibility for the issue until it got resolved.
- Produced trend analyses of the production incidents to provide feedback to development teams.
- Trained professionals on the applications involved in the online store.
Technologies: Cross-departmental Collaboration
Team Leader
2007 - 2008
Compasso (via Sicredi Bank)
- Managed a team of business analysts, technical analysts, and developers on integration projects between the legacy ERP and the new ERP using Oracle ODI.
- Worked as an interpreter between the subject matter experts from the Indian ERP company and the local analysts that only spoke Portuguese.
- Distributed tasks to the analysts and developers and followed up towards resolution.
- Led daily standup meetings towards keeping everybody up to date with the latest from the project.
Technologies: PMBOK, Oracle ODI
Team Leader
2006 - 2007
CPMBraxis (via Deutsche Bank)
- Led a team working on auditing/reporting Deutsche Bank UK projects. I was also responsible for providing third-level support to an auditing application, which ensured that the data produced by a number of applications were correct.
- Reported status updates to the upper management weekly.
- Mentored professionals towards improving their careers.
- Implemented pre-sales processes and participated in those pre-sale events.
- Interviewed candidates looking to find top-notch talent for the projects.
Technologies: Java, Unix, Oracle, Microsoft SQL Server
Senior Java Developer
2004 - 2005
Dell
- Worked as a Java developer on the application responsible for communication with vendors on the software and peripherals store at Dell.com.
- Wrote modules to produce sales reports using JDBC queries and exporting to CSV files.
- Built XML parsing modules necessary to provide additional features to the vendors that had their ERPs connecting to our application.
- Worked on requirement clarification processes with the US team.
- Helped improve the logging of the application, producing more detailed data.
Technologies: Oracle, Jakarta Server Pages (JSP), Jakarta EE (Java EE or J2EE), Java, Web Services Description Language (WSDL), Server-side Rendering (SSR)
Java and COBOL Developer
2001 - 2004
CPM Braxis Capgemini (via Bradesco Bank)
- Developed COBOL modules for the banking industry. These modules ranged from reports to data processing modules that would read data from either text files or Db2 databases and produce output files with the updated data.
- Developed servlets that interacted with the COBOL modules and displayed data in JSPs.
- Tested the integrations between the COBOL and Java parts of the framework.
- Conducted software peer reviews of my colleagues, providing objective feedback on their work.
- Helped setup version control so that the team could be more productive.
Technologies: Apache Tomcat, Jakarta EE (Java EE or J2EE), COBOL
Experience
Shopping Budget — Variation of Knapsack
https://github.com/flaviopezzini/shoppingbudget-permutation/Problem Description:
Molly wants to buy laptops for her school, and I use Java to determine how many laptops she can purchase by comparing the vendors available. Each vendor sells the laptops in batches, with a quantity identifying how many laptops are in each batch, the price for the whole batch, and the parameters determining which laptop batches Molly should purchase for her school based on the available batch size and price.
I developed a Java-based solution that required permutation and dynamic programming. It involved a variation of the common knapsack 0/1 solution.
Sample input: 50 [20,19] [24,20]
• Molly has 50 dollars to spend.
• The first vendor has 20 laptops per batch, and each batch costs 24 dollars.
• The second vendor has 19 laptops per batch, and each batch costs 20 dollars.
The possible answers are 40 and 38.
If she buys from the first vendor, she will spend 48 dollars (24*2), and since she's buying two batches, the total quantity is 40 (20*2). However, if she buys from the second vendor, the maximum amount would be 38 since each batch has 19 laptops, and she'd run out of money after the second batch.
The final answer is then 40 since 40 is higher than 38.
Molly wants to buy laptops for her school, and I use Java to determine how many laptops she can purchase by comparing the vendors available. Each vendor sells the laptops in batches, with a quantity identifying how many laptops are in each batch, the price for the whole batch, and the parameters determining which laptop batches Molly should purchase for her school based on the available batch size and price.
I developed a Java-based solution that required permutation and dynamic programming. It involved a variation of the common knapsack 0/1 solution.
Sample input: 50 [20,19] [24,20]
• Molly has 50 dollars to spend.
• The first vendor has 20 laptops per batch, and each batch costs 24 dollars.
• The second vendor has 19 laptops per batch, and each batch costs 20 dollars.
The possible answers are 40 and 38.
If she buys from the first vendor, she will spend 48 dollars (24*2), and since she's buying two batches, the total quantity is 40 (20*2). However, if she buys from the second vendor, the maximum amount would be 38 since each batch has 19 laptops, and she'd run out of money after the second batch.
The final answer is then 40 since 40 is higher than 38.
Strava App to Format the Athlete Weekly to Copy/Paste to an Internet Forum
https://github.com/flaviopezzini/stravaweeklyA Spring application that uses OAuth2 to connect to Strava using the Athlete's credentials and pulls the latest week of exercises and formats it nicely so it can be posted on internet discussion boards.
Comparing Poker Hands in Rust
https://github.com/flaviopezzini/rust-poker-handA Rust program to compare Poker Hands using all the poker rules; for instance, a pair is stronger than a high card, a flush is stronger than a pair, and so on.
It served as a starting point in my track towards learning Rust.
It served as a starting point in my track towards learning Rust.
A Desktop App with Tauri and React to Format JSON
https://github.com/flaviopezzini/tauri-json-beautifer-converterThis is a Tauri app that utilizes Rust as its back end and React as its front end. It can be easily compiled and run on both desktop and Android/iOS.
It beautifies/minifies JSON content, and also converts JSON to either YAML or XML.
It beautifies/minifies JSON content, and also converts JSON to either YAML or XML.
Campsite Booking Application
https://github.com/flaviopezzini/campsite-bookingA Spring Boot application to manage reservations to a campsite.
Availability is created in the database, and then it is filled as reservations arrive.
It's relatively database-agnostic, but I would recommend PostgreSQL as the database.
Availability is created in the database, and then it is filled as reservations arrive.
It's relatively database-agnostic, but I would recommend PostgreSQL as the database.
Education
2005 - 2006
MBA in Business Administration and Management, General
Fundação Getulio Vargas - Porto Alegre, RS, Brazil
2002 - 2003
Certificate in Web Development
Universidade Tecnológica Federal do Paraná, Pato Branco - Pato Branco, Brazil
Certifications
DECEMBER 2025 - DECEMBER 2028
AWS Certified Cloud Practitioner
Amazon Web Services
Skills
Libraries/APIs
Spring REST, Jackson, REST APIs, API Development, Stripe API, Stripe, JOOQ, Graph API, React, JSTL, Java Message Service (JMS), Jenkins Pipeline
Tools
Apache Maven, Git, IntelliJ IDEA, RabbitMQ, Claude, NGINX, Kafka Connect, Logging, Docker Compose, Kafka Streams, Bitbucket, GitHub, Claude Code, Codex, Jira, SonarQube, Amazon Simple Notification Service (SNS), Jenkins, Helm, Apache Tomcat, SoapUI, ActiveMQ, Amazon Simple Queue Service (SQS), AWS IAM, Amazon Elastic Container Service (ECS)
Languages
Java, JavaScript, TypeScript, Rust, SQL, Python, HTML, Java SE (Core Java), Web Services Description Language (WSDL), COBOL, Hibernate Query Language (HQL), CSS, HTML5, Kotlin, Bash Script
Frameworks
JPA, Angular, Spring, Jakarta Server Pages (JSP), Spring Security, Spring Boot, JUnit, JSON Web Tokens (JWT), Java Persistence API (JPA), Hibernate, Mockito, OAuth 2, AngularJS, Selenium, Apache Velocity, Hydra, Tauri
Paradigms
REST, Microservices, Database Design, Event-driven Architecture, Event-driven Design (EDD), Test-driven Development (TDD), Real-time Systems, Object-oriented Programming (OOP), Microservices Architecture, Unit Testing, Continuous Delivery (CD), Continuous Integration (CI), Automation, Refactoring, Application Architecture, Redis Pub/Sub, Role-based Access Control (RBAC), Back-end Architecture, ETL, Desktop App Development, DevOps
Platforms
Jakarta EE (Java EE or J2EE), Unix, Linux, Java EE (Jakarta EE), Amazon Web Services (AWS), JVM, Google Cloud Platform (GCP), Azure, Firebase, Confluent Kafka, Apache Kafka, Docker, Kubernetes, Amazon EC2, JBoss, Oracle, Google Cloud SDK, AWS IoT
Storage
JSON, Spring Data, PostgreSQL, Spring Data REST, MongoDB, Redis, Spring Data JPA, Databases, Relational Databases, Database Migration, NoSQL, Database Architecture, MySQL, Microsoft SQL Server, Amazon S3 (AWS S3), Google Cloud
Industry Expertise
Project Management, High-frequency Trading (HFT), Trading Systems
Other
SOAP, API Design, Software Architecture, Full-stack Development, Back-end, APIs, Data Security, User Interface (UI), API Integration, Architecture, Distributed Systems, Metrics, Performance Optimization, Code Review, Springbot, Back-end Development, Front-end Development, Code Deployment, Authentication, Single Sign-on (SSO), Debugging, Webhooks, Document Processing, Workflow Automation, Full-stack, Team Leadership, Message Queues, Solution Architecture, Data Modeling, Multi-tenant SaaS, Multi-tenant Architecture, Scalability, Access Control, Non-relational Databases, Cursor AI, Enterprise Architecture, Cloud, WebSockets, Software as a Service (SaaS), Algorithms, Code Auditing, Low-latency Software, Real-time Data, Reporting, System Design, Security, Server-side Rendering (SSR), Redis Streams, AWS Secrets Manager, Efficient Data Serialization, Fintech, Payment Gateways, Event-driven Systems, Software, Software Development, Technical Documentation, Technical Leadership, Enterprise Systems, Troubleshooting, Documentation, SDKs, PDF, Large-scale Projects, IT Project Management, Software Engineering, Hibernate Validators, CI/CD Pipelines, Microsoft Graph API, Pub/Sub, Containerization, Trading, Front-end, User Experience (UX), Cloud Architecture, GCP DevOps, Automated Trading Software, Shell Scripting, Web Services, Web Development, Leadership, Agrona, FIX Protocol, Distributed Software, Asynchronous Data Streams, Minikube, Messaging, Caching, Data Marshalling, Amazon RDS
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