Senior Backend Developer
Crafting ScalableJava & Python Solutions
Crafting Scalable Java & Python Solutions
More than 7 years of experience building robust systems with Java and Python, focused on clean architecture, APIs, integrations, and scalable cloud-ready solutions; Implementing enterprise environments with Docker, Kubernates or Event Streaming Managers. I've led end-to-end backend initiatives designing secure and high-availability solutions, Using the best technologies as a Terraform, CI/CD with Jenkins, cloud services on AWS, Azure or GCP, and large-scale migration tools.
Professional Profile
Quality Solutions
Make Great Software
About me
Hi, I am Alejandro Valencia, a Senior Backend Developer and Tech lead with more than 7 years of experience leading and delivering strategic projects in enterprise environments. I specialize in designing and implementing scalable, secure, and high-performance backend solutions using Java and Python, with frameworks like Spring, Hibernate, Jakarta EE, Flask, FastAPI and Django.
Following best standards, patterns, architectures, testing practices, and quality assurance, I am able to release great software that meets real company needs. I have led large-scale, critical migrations and modernization efforts, certified as a Scrum Master and Product Owner.
AWS, Azure, GCP, Terraform (IaC), Jenkins, Git, Docker, Kubernates, Event Streaming, and many other technologies have become my everyday tools to achieve major goals, which has given me strong mastery and expertise, not only in the tools themselves, but also in solving real-world business problems.
I incorporate LLMs and prompt engineering into my workflows to accelerate technical analysis, documentation, and the generation of common software artifacts while maintaining an unwavering focus on quality, security, and traceability.
Java and Python
Senior developer with experience in frameworks like Spring, Hibernate, Jakarta EE, Flask, FastAPI and Django.
Quality Assurance
Ensuring software quality through comprehensive testing, code reviews, and adherence to best practices.
Design Patterns and Principles
SOLID principles, Patterns like Factory, Singleton, and Observer, all this standards were making to ensure code quality and maintainability, that is the type of work that I enjoy the most in my career.
REST and SOAP APIs
Nowdays, I specialize in designing and implementing RESTful and SOAP APIs, ensuring seamless integration and optimal performance, Guarantees the best user experience and microservices architecture
Work Experience
Senior Full-Stack Java/Python AWS Developer
- Salesforce Marketing Cloud: Designed the full architecture, diagrams, technical designs, and implementation modules using AWS, Azure, Terraform, Git, Jenkins, Splunk, Java, and Python, increasing campaign success rates by 45% and profitability by 25%.
- MongoDB to Amazon DocumentDB migration: Built large-scale data validation tooling, modernized infrastructure, migrated APIs to Node.js, Java, and Python, and refactored hundreds of queries, reducing database costs by nearly $15,000 per month.
- Core payment services optimization: Removed bottlenecks, reduced front-end response times, and improved query and transaction speed by 60%.
- New API delivery: Built a FastAPI integration API for Salesforce and a Java Spring Boot API for Ascent.
Software and Architecture Consultant
- Java 8 to Java 21 migration: Migrated the traffic fines payment module from Java 8 to Java 21 and developed technical documentation and a new REST API to support future payment processing modules.
- Performance improvement: Improved Oracle 13c database query performance by 40% in the payments and reporting modules and standardized database connectivity through the development of a new shared module.
- New React Admin panel: Developed the React frontend for the user management and traffic fines inquiry/payment modules, implementing session management, caching, Redis integration, encryption, and secure authentication
Backend JAVA/Python Software Engineer, Senior
- New mobile app development: Participated in the development of a new mobile app for banking products, following Domain Driven Design principles and Python frameworks like FastAPI, Django and Flask supporting it on Pydantic and pytest over AWS and Azure cloud platforms.
- Microservices and domain modeling: Designed and implemented domain models and business logic across multiple microservices using Python and Java, applying Domain-Driven Design (DDD) principles to support scalable banking services for microloans and low-balance account management.
- Cloud-native backend services: Developed and deployed RESTful backend services within AWS, Azure, and GCP environments, integrating API Gateway patterns, SQL and NoSQL databases, and CI/CD pipelines to support high-throughput financial transactions and reporting systems.
Tech lead and Senior Developer Analyst,
- Core banking integration architecture: Designed and implemented the inter-application communication backbone by building an API Gateway and mediation layer with 94+ REST and SOAP services, plus a translation API to integrate legacy banking systems with modern platforms.
- Enterprise data modernization: Cataloged and standardized 130+ ETL jobs and reporting pipelines, and contributed to their migration to modern data platforms including AWS Glue, Azure Data Factory, and GoAnywhere.
- Regulatory and operational readiness: Produced technical standards, operating manuals, and integration documentation required to meet banking regulatory and audit requirements, supporting the successful rollout of the institution’s new Core Banking ecosystem.
Developer Analyst and FLEXCUBE Migration Lead
- FLEXCUBE migration leadership: Designed the end-to-end technology architecture and migration rules for the transition of active loan portfolio products into Oracle FLEXCUBE, while serving as a Production Solutions Consultant and leading an 11-person team through delivery.
- High-impact banking migration: Contributed to the successful migration of Revolving Credit and Personal Loan products, achieving a 99.8% success rate across 39,000 customers and 80,000 loans, enabling a reliable transition to the bank’s new core banking model.
- Data and operational optimization: Built 15 ETL pipelines using DataStage, optimized 5 production ETL processes involved in loan portfolio closing, reducing execution time by 1.5 hours, and improved ODS and FLEXCUBE queries to strengthen reporting and business decision-making.
Highlighted Projects
Salesforce Marketing Cloud
Data Base Migration
Wompi Payments
Traffic fines payment module
Android APP BOLD CF
Core Banking System
FLEXCUBE Migration Program
My Skills and technologies
The Tools Behind
Exceptional Software
Personal Projects
The Best Resume
Is Your Work
Terraform Jenkins on DigitalOcean
This Infrastructure as Code project provisions a Jenkins server on DigitalOcean with Terraform, persistent storage, DNS, firewall rules, Docker, and Nginx, creating a compact self-hosted CI/CD environment exposed securely over HTTPS.
Public Endpoint https://www.jenkinsnauthsoftwareprivate.appAzure VM Terraform + LocalStack
This Terraform and Jenkins setup provisions an Azure environment with networking, DNS, persistent storage, Docker, Nginx, a static website, and LocalStack behind custom domains with TLS for repeatable single-server automation.
Public Endpoint https://localstack.nauthappstest.tech/_localstack/healthLocalStack AWS Automation Lab
This Jenkins-based automation lab deploys AWS-like resources into LocalStack with Terraform or AWS CLI, handling preflight checks, credentials, deployment artifacts, and optional Azure-backed Terraform state from one pipeline.
Public Endpoint https://nauthappstest.techSpring Boot Multi-App Platform
This Spring Boot project centralizes and serves multiple web applications from a single backend, organizing routing, templates, static assets, and shared presentation logic to expose portfolio-style app experiences from one platform.
Public Endpoint https://alejandrovalencia.site/Contact Me
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