Hire the Best Apache Cassandra Developers

🥇TOP RATED PLUS | 👨🏻‍💻 4000+ WORKING HOURS 💼 7+ YEARS EXPERIENCE | 🏆100% Job Success ⭐️⭐️⭐️⭐️⭐️ "I had the pleasure of managing Dasun (Era), a senior software engineer, on our recent project, and I must say, it was a fantastic experience. Era's code was top-notch, well-structured, and he always delivered more than we expected. What really stood out was Era's communication skills; he kept the team in the loop, asked smart questions, and had great suggestions. Working with Era was a breeze - he was professional, met deadlines, and handled challenges with ease. I can't wait to hire him again ASAP; he's a star in our team! ⭐️⭐️⭐️⭐️⭐️"I was very happy with the work from Era on a spring web flux project. He produced code that was excellent quality and proactively fixed issues and made improvements as he worked through the tasks." I am a seasoned software engineer with over 7 years of experience, specialising in Java, Spring Boot, and REST API development. My passion lies in tackling new challenges and establishing long-lasting collaborations that drive innovation and excellence in every project. Technical Expertise: ✅ Proficient in Java, including Java 8, Java 11, Java 17. ✅ Expertise in developing web applications in the Banking and Financial domain for over the 5 years. ✅ Backend development experience with Spring Boot Spring webflux, REST API development, application security, scalability, and proficiency in Spring Data JPA, Hibernate, Spring Cloud, and Spring Security. ✅ Proficiency in Microservice design pattern with Clean code principals and Domain Driven Design and inter service async communication with Event-Driven architecture, CQRS (Command Query Responsibility Segregation), SAGA patterns, Load balancing, Config management, and Gateway implementation. ✅ Knowledge of application security best practices, including OAuth 2 implementation, JWT token-based authentication, and authorization. ✅ Experience in Test-Driven Development (TDD) and unit testing using JUnit 5 and Mockito, as well as snapshot testing with Jest and Enzyme. ✅ Familiarity with both relational and NoSQL databases, including MySQL, Oracle, PostgreSQL, MongoDB, and Amazon QLDB. ✅ Hands-on experience with AWS, including designing and implementing highly scalable and secure infrastructure plans, application deployment, and CI/CD pipelines using AWS services like CodeCommit. Proficiency in migrating on-premises applications to the AWS cloud. ✅ Expertise in DevOps practices, including CI/CD with Jenkins and GitHub Actions, containerization using Docker, terraform script development, Ansible, Container Orchestration with Kubernetes clusters and Amazon EKS (Elastic Kubernetes Service), and version control using Git. ✅ Experience in setting up monitoring and logging solutions like Prometheus, Grafana, ELK (Elasticsearch, Logstash, Kibana), or AWS CloudWatch to ensure the health and performance of applications. ✅ Understanding of distributed system concepts, including message brokers like Apache Kafka or RabbitMQ, and the implementation of distributed transactions. ✅ Expertise in optimising application performance, including profiling, caching strategies, and database query optimisation. ✅ Proficiency in modern Software Development Life Cycle (SDLC) methodologies, including Agile (SCRUM), and tools such as Jira, Confluence, and SonarQube. ✅ Mastery of Object-Oriented Programming (OOP) concepts, SOLID principles, and Data Structures & Algorithms. I have a proven track record of delivering exceptional results for my clients, including: ☑ Boosting client revenue by 30% through targeted web application improvements. ☑ Increasing code quality by 80% using best practices and the Boy Scout Rule. ☑ Mentoring junior developers to enhance their Java skills and problem-solving abilities. I am confident that my strong technical background and commitment to excellence will make me an asset to your team. If you would like to discuss how I can contribute to your next project, please don't hesitate to reach out. Thank you for considering my application, and I look forward to speaking with you soon. Best regards, Dasun.

Slow databases? Production outages? Performance bottlenecks affecting your business? I help organizations identify root causes, optimize database performance, and build reliable database platforms. I am a senior database administrator (DBA) with over 13 years of hands-on experience managing production database systems. I specialize in MySQL, MariaDB, PostgreSQL, MongoDB, Oracle , and SQL Server, providing database troubleshooting, incident response, daily operations and maintenance, performance optimization, and reliable backup, high availability, and disaster recovery solutions for mission-critical environments. 🔍 Database Expertise: With over 13 years as a senior expert in MySQL/MariaDB/Percona/PostgreSQL/MongoDB/Oracle/SQL Server/DuckDB, I’ve managed over 5000 databases and 300 TB+ of data. My experience covers database architecture, performance optimization, backup and recovery, High availability, disaster recovery, and much more. I ensure every database solution I deliver is robust, scalable, high performance, and perfectly aligned with your business needs. 🛠️ Technology Stack: MySQL/Percona (Versions 5-9) MariaDB (Versions 5-12): Installation、High Availability, Replication, and Scalability Solutions、InnoDB Cluster、Group Replication、Workbench/Shell/Router、Backup & Restore、Galera Cluster、Percona XtraDB Cluster、XtraBackup、Toolkit、InnoDB/MyISAM/Binlog、Orchestrator、replication-manager. PostgreSQL (Versions 7-18): Installation、High Availability, Replication, and Scalability Solutions、SQL Tuning、pgpool-II、PostGIS、TimescaleDB、ClickHouse、Patroni、Citus、pgvector、Security、Supabase、Neon. MongoDB (Versions 3-8) / MongoDB Atlas : Installation、MongoDB Shell (mongosh)、Aggregation、Indexes、Atlas、Time Series、Change Streams、Replication、Sharding、Storage、Administration、Security. SQL Server (Versions 6.5 – 2025): Installation、High Availability and Disaster Recovery (Always On AG, FCI, Log Shipping, Replication)、Distributed Availability Groups、SQL Server Management Studio / Azure Data Studio / sqlcmd、Backup & Restore、Failover Cluster / Always On Solutions、PowerShell dbatools / First Responder Kit、Storage Engine / Transaction Log / Change Data Capture. Other Database : Oracle、DB2、Redis、SQLite、DuckDB、DocumentDB Cloud service providers: AWS RDS、AWS Aurora、Amazon DocumentDB、GCP、Azure、N8N creator. Certifications: I hold certifications from Cisco, Oracle, MySQL, AWS, ITIL, PMP, and TOGAF, ensuring I bring industry-recognized expertise to every project. 📈 Why Choose Me? Proven Experience: Worked for leading ICT and IoT solution providers, supporting major operators, banking, and financial enterprises. End-to-End Solutions: From designing high availability architectures to delivering query optimizations and backup solutions, I offer complete database management expertise. Training & Support: I also provide course training for companies looking to empower their teams with database-related skills. 🤝 Let’s Collaborate: If you’re looking for a seasoned database professional to tackle challenges in MySQL, PostgreSQL, MongoDB, Oracle, or other database technologies, let’s discuss how I can help streamline your operations and enhance performance. 📩 Contact Me: I’m ready to dive into your project. Reach out, and let’s unlock the full potential of your data infrastructure together!

I am a senior software developer and architect (Total- 21 Yrs.) in Java/J2ee, Python, Rest API, SOAP API, javascript, OAuth, SSO, React, Redux, Angular, Kafka, SpringBoot, JPA, Cloud, AWS, Azure, Private cloud, JBPM, n8n, Oracle BPM, JMS, Hibernate, Struts, Spring Batch, ESB, Base44, Playwright, Selenium, JavaFX, Lisp, Prolog, Weka , OpenAI, Different Web as well as Application Servers, different Operating Systems and DBMS Tools, SQL, NoSQL, PostgreSQL, Mongo, Cassandra, MYSQL, Oracle, Supabase, AI, NLP, OpenAI, agent development, Wordpress, php , CI/CD, Agile and various open-source tools, technologies and frameworks. Some of the domains I have worked on are Banking, finance, Trade, Crypto, HR, Insurance, Learning, NLP, Healthcare, System architecture, Developers Tooling, Document management, AI, DevOps, Cloud, GCP, Hubspot, Quickbook, PandaDoc, etc. ********************************************************************* Experience Summary: Freelancing || Freelancing || Present Toyow, Mumbai || Solution Architect || Sep 24 to JAN 25 JPMorgan, Mumbai || Vice President || Jun 15 to July 24 and May 10 to Jun 13 || (Around 12 Yrs.) Deloitte, Mumbai || Senior Consultant/Specialist Senior || Jun 13 to Jun 15 HCL Technologies || Onsite/Offshore Dev lead || Sep 06 to May 10 Birla Soft Ltd || Software Engineer || Jan 06 to Sept 06 GIIT, Gr. Noida || Developer || Feb 05 to Oct 05 ************************************************************************* Some of the applications are as below which I have developed/contributed. - Document generation system - Online translation system using NLP - Library management system - HRMS System - Networking system - Tools for Developer and Operate to build and deploy their applications. - Workflow as a service - Workflow Platform for Mutual Fund NAV processing (Fund accounting) - Prediction analysis for SLA miss. - A real time dashboard for fund processing - Messaging Platform supporting MQ, SFTP, REST, Kafka, FIX, - Trade instruction manager - Customer support system for Bank operators - Platform for Tokenization Assets using Blockchain - A social Media application - A insurance management Platform - Applications developed on Base44 - Loan record reports - OCR for healthcare reports and data processing. - ChatBot for Patient enquiry - Coin analysis using AI (openAPI integration)

Data Engineer specializing in Python ETL pipelines for cloud data warehouses. I build automated data engineering solutions processing millions of records daily, from real-time trading data to healthcare analytics. With over 6 years of experience, I have developed production ETL systems on GCP and AWS using Apache Airflow, Dagster, and modern data stacks. I architect data engineering solutions that handle schema changes, ensure data quality, scale with demand, and prevent 3 AM pipeline emergencies. DATA ENGINEERING & ETL EXPERTISE ETL Pipeline Development & Data Engineering I design scalable ETL pipelines and data engineering infrastructure using Python with Apache Airflow or Dagster. My solutions include automated error handling, data validation, and comprehensive monitoring. Cloud Data Engineering (GCP & AWS) I build cloud-native data engineering solutions and ETL pipelines on modern platforms: GCP: BigQuery, Dataflow, Cloud Functions, Pub/Sub AWS: Redshift, Glue, Lambda, S3, Kinesis Enterprise Data Warehouse Migration Reduced ETL processing time by 60% moving to GCP. Python Data Engineering & Pipeline Orchestration Python expert for data engineering and ETL development. I implement robust data workflow orchestration using Apache Airflow and Dagster with pipeline monitoring for data quality and reliability KEY DATA ENGINEERING & ETL PROJECTS - Election Data Pipeline: Python + Dagster + Clickhouse solution extracting campaign finance data, automating 40 hours/week of manual processing. - Real-Time Trading Pipeline: Multi-layer architecture for algorithmic trading, achieving <100ms latency and 100% uptime. - Healthcare Data Migration: Led enterprise ETL migration to GCP BigQuery, resulting in 60% faster processing and 50% better performance. - ML Feature Engineering: Built end-to-end data pipeline for AirAsia's recommendation system, processing millions of records and increasing engagement by 25%. - Web Scraping ETL: Automated solution combining scraping with warehousing using Python and Apache Airflow. - AWS Cloud System Stabilization: Enhanced stability and performance of AWS-based systems, focusing on S3, Lambda, and webhook integrations. - Manufacturing Data Platform Expansion: Supported and expanded a manufacturing data platform with SQL Server, Azure SQL, and ERP data mappings. DATA ENGINEERING TECH STACK ETL & Orchestration: Apache Airflow, Dagster, Apache Spark, Kafka, dbt Languages: Python (Expert), SQL (Expert) Cloud Platforms: GCP (BigQuery, Dataflow), AWS (Redshift, Glue, Lambda) Databases: PostgreSQL, Clickhouse, MongoDB, BigQuery, Redshift, Snowflake Python Libraries: Pandas, PySpark, SQLAlchemy, Apache Beam Infrastructure: Terraform, Docker, Kubernetes, CI/CD IDEAL PROJECTS ETL pipeline development from scratch (Python, Airflow, cloud platforms) Data warehouse engineering and cloud migration (BigQuery, Redshift, Snowflake) Real-time data engineering and streaming ETL implementation Legacy ETL modernization and data pipeline migration Web scraping data engineering with ETL workflows Data integration connecting multiple sources ML data pipeline engineering for feature engineering LET'S BUILD YOUR DATA ENGINEERING SOLUTION Available for fixed-price data engineering projects and long-term ETL contracts. I work across US, European, and Asian time zones (GMT+7). Ready to discuss your data engineering and ETL needs? Send me a message. I respond within 2 hours during business hours.

🏆 Top-Rated Database Architect & Multi-Cloud Specialist with 16+ Years of Experience Delivered 50+ enterprise-scale database and cloud transformation projects across telecom, government, banking, retail, and transport industries, specializing in migrations, HA/DR architectures, and performance tuning for Oracle, PostgreSQL, MySQL, SQL Server, MongoDB, Redis and Apache Cassandra. I am a seasoned Database Architect and Cloud Specialist with over 16 years of experience, delivering high-impact solutions across telecom, government, banking, transport, and retail industries. My expertise spans multi-database ecosystems (Oracle, PostgreSQL, MySQL, SQL Server, MongoDB, Redis) with a strong focus on performance tuning, HA/DR architectures, and enterprise-scale migrations. Beyond databases, I bring deep experience in multi-cloud environments (OCI, AWS, Azure, GCP) and DevOps practices, leveraging Kubernetes, Docker, Ansible, Jenkins, and CI/CD pipelines to design and automate resilient, scalable infrastructures. Over the years, I have led critical modernization projects including Oracle RAC/Data Guard, PostgreSQL Patroni clusters, MySQL InnoDB clusters, SQL Server Always-On, and GoldenGate microservices replication, all aligned with compliance, cost optimization, and business continuity. I specialize in cloud-native architectures, database modernization, and containerized deployments, ensuring secure, high-performing, and future-ready platforms for enterprises across multiple sectors. 🔹 Database Expertise High Availability & DR: Oracle RAC/Data Guard/GoldenGate, PostgreSQL Patroni/repmgr/EFM, MySQL Group Replication/ClusterSet, SQL Server Always-On, MongoDB ReplicaSets & Sharding, Redis Sentinel & Cluster. Performance Tuning: Advanced SQL optimization, query indexing, connection pooling, and OS-level tuning (CPU, memory, I/O, networking). Clickhouse DB optimization and performance tuning. Migrations: End-to-end cross-platform migrations (SQL Server → Postgres/Oracle, MySQL → Snowflake/OCI/Azure, on-prem → multi-cloud). I have hands-on experience designing and implementing Oracle Fusion API integrations using Oracle Integration Cloud (OIC), connecting Fusion Cloud with multiple external systems. My work includes building and optimizing REST and SOAP-based services, handling complex data mappings, and improving integration performance and reliability. I’ve also maintained existing integrations to ensure high availability and seamless data flow while collaborating closely with cross-functional teams to identify needs, streamline workflows, and deliver well-documented, reusable integration solutions. Automation: Backup/recovery orchestration, PITR, monitoring, and administration via shell scripts, Ansible, Jenkins, and IaC. 🔹 Cloud Architecture Certified in OCI, AWS, Azure, GCP, and Alibaba Cloud, with deep experience in hybrid & multi-cloud setups. Skilled in OCI Exadata Cloud@Customer, AWS RDS/Aurora, Azure SQL Database, Databricks, and multi-region failover. Migrated enterprise systems (DB + middleware) to cloud with zero-downtime cutovers and automated DR. 🔹 DevOps & Modern Platforms Proficient with Docker, Kubernetes, and OpenShift for containerized DB + application deployments. Extensive experience in building, optimizing, and maintaining Oracle Integration Cloud (OIC) processes, adapters, and orchestration for enterprise-scale clients. VBCS (Visual Builder Cloud Service): Skilled in designing and developing responsive, low-code applications integrated with Oracle SaaS and PaaS ecosystems. Strong background in CI/CD (Jenkins, GitLab, Ansible, Terraform). Experience securing secrets with Vault, integrating monitoring stacks (Prometheus, Grafana, ELK). 🔹 Odoo & Application Layer Odoo deployment, backend DB optimization, and module customization. Report building & tailoring business workflows for performance and usability. Tomcat, Apache, IBM WebSphere, Oracle WebLogic, and Bitnami stack administration. 🔹 Data & AI Solutions Data Engineering & Warehousing: Azure Data Factory, Databricks, Oracle OBIEE, Snowflake. AI Agent Development: Built agents for self-healing DBs, N8N automation, and natural language querying. Supabase Consultation: Connect Supabase with AI agents to simplify backend management for non-developers. Automate project provisioning, query execution, function creation, and API management. Enable natural language interaction with data, making database operations accessible to entire teams. ✅ Key Certifications: Oracle 19c OCP DBA | PostgreSQL Advanced v11 | MySQL 8.0 OCP | MongoDB Associate DBA | Redis Certified Developer | Microsoft Azure Administrator | OCI 2025 Certified Multicloud Architect | OCI GenAI | Oracle GoldenGate Implementation Specialist | WebLogic 12c OCP | YugabyteDB DBA

It was the most important moment of my 13+ years of career. It was when I realized that there is always a trade-off in technology. You have to do something intentionally bad in order to succeed as a Small Medium Business in the Digital Transformation. And 70% fail because they insist on doing this very thing well. A while back, when I finally landed a job in a corporation, I was excited that I was going to use state-of-art technology. But, one of my first features immediately added some bugs. As I fixed those bugs, I introduced another, but also other bugs started to pop up caused by previous developers. In laymen terms, it is like a Rubik’s cube. As you carry on assembling the second face, you may accidentally mess up the first bit. It wasn’t like that when I started my career in technology in the civil service a long time ago. Yes, I was frustrated because we used old boring technology. But, we didn’t have to put out the fire all the time because that limited technology prevented us from getting in this position. Coincidence or not, the easiest way to solve the Rubik’s cube is putting constraints. If you move towards, you have to move backwards at some point. Fast forward to nowadays, some of my clients want to create highly customized User Experience. As the project starts to grow, hyper customization introduces more complexity. Then, you make a small change and get unexpected results. You didn't account for all the complex consequences. And this happens again and again, and you can’t avoid it. The software had become brittle. You start to miss deadlines or have to hire more developers to fix cracks faster, and eventually I get hired. That’s the time I have the hard talk: don’t bite more than you can chew, stop chasing the perfect User Experience (good User Interface is not a problem though) with a small team. If a BigTech didn’t have to hire thousands of engineers to provide that, they certainly wouldn’t. Anyway, User Experience is only noticed by B2C clients, and this is where Big Techs thrive. In B2B or internal tool software, who pays for the software won’t even use it. Hey, my name is João, I’m a software architect and developer, feel free to send me a message asking how I can make your business grow. What technologies do I work with? The simple ones: HTML, CSS, Bootstrap, Bash, XML, PostgreSQL, Apache Camel, Apache Knowledge Is Everything, Keycloak. If you need a hypercustomized solution, I can decently program in Java, Python and JavaScript, though. If you have any doubts, don’t hesitate to contact me.