Rejoy Sebastian, Developer in Kochi, India
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Rejoy Sebastian

Verified Expert  in Engineering

Business Intelligence (BI) Developer

Location
Kochi, India
Toptal Member Since
June 18, 2020

Rejoy is a result-oriented data engineer with more than eight years of development experience in data analytics, design, and development of BI solutions. He designs and develops reports and dashboards using multiple platforms and data sources, including AWS. Rejoy thrives in a fast-paced environment with cross-functional teams within Agile methodology.

Portfolio

Vertizone IT Pvt Ltd
Amazon Web Services (AWS), Pentaho, PostgreSQL, Amazon EC2, Amazon S3 (AWS S3)...
KPMG
iDashboards, Microsoft SQL Server, Pentaho, Data Visualization
Vertizone IT Pvt Ltd
Amazon Web Services (AWS), Pentaho, PostgreSQL, Amazon EC2, Amazon S3 (AWS S3)...

Experience

Availability

Part-time

Preferred Environment

Linux, Amazon S3 (AWS S3), Redshift, Pentaho, SQL, Looker, Sisense, Snowflake, Amazon EC2, Dashboard Design

The most amazing...

...thing I've done was work on projects to migrate dashboards from Periscope to Looker and Sisense, with Snowflake and Redshift as respective source databases.

Work Experience

BI Developer

2015 - 2017
Vertizone IT Pvt Ltd
  • Developed data marts using AWS cloud computing tools like EC2, S3, and Redshift.
  • Created and maintained Redshift clusters according to client requirements.
  • Developed and deployed ETLs using a Pentaho Data Integration to automate data processing in Redshift.
  • Managed performance optimization in Redshift and ETLs.
  • Coded, designed, and scheduled reports in Pentaho Report Designer 3.9, 5.0, and 5.1.
  • Developed complex SQL codes required for reports and ETLs.
  • Gained coding experience in MySQL and Postgres database tools.
Technologies: Amazon Web Services (AWS), Pentaho, PostgreSQL, Amazon EC2, Amazon S3 (AWS S3), Redshift, Pentaho Data Integration (Kettle), Pentaho Reports, Data Visualization

Executive

2014 - 2015
KPMG
  • Developed ETLs using Pentaho Data Integration.
  • Maintained a data warehouse in a SQL server.
  • Developed complex SQL codes required for iDashboards and ETLs.
Technologies: iDashboards, Microsoft SQL Server, Pentaho, Data Visualization

BI Developer

2014 - 2014
Vertizone IT Pvt Ltd
  • Developed data marts using AWS cloud computing tools like EC2, S3, and Redshift.
  • Created and maintained Redshift clusters according to client requirements.
  • Developed and deployed ETLs using Pentaho Data Integration to automate data processing in Redshift.
  • Optimized the performance in Redshift.
  • Coded, designed, and scheduled reports in Pentaho Report Designer 3.9, 5.0 and 5.1.
  • Developed complex SQL codes required for reports and ETLs.
  • Gained coding experience in MySQL and PostGres database tools.
Technologies: Amazon Web Services (AWS), Pentaho, PostgreSQL, Amazon EC2, Amazon S3 (AWS S3), Redshift, Pentaho Data Integration (Kettle), Pentaho Reports, Data Visualization

Software Engineer

2013 - 2013
Verbat Technologies
  • Designed and automated various daily, weekly, and monthly report generation.
  • Gained experience in SQL development.
  • Designed reports in Pentaho.
  • Created ETLs to automate report generation.
  • Worked with different database tools like MySQL, MS SQL server, and Teradata SQL assistant. I also provided SQL coding support for other development teams.
Technologies: SQL, Teradata, Pentaho Reports, Pentaho Data Integration (Kettle), Microsoft SQL Server, Data Visualization

Developer

2011 - 2012
NH Infomedia
  • Handled server administration at a client's place.
  • Made backup plans for an Oracle 10g-based database.
  • Performed daily monitoring of the production environment.
  • Monitored and reorganized tablespaces, data files, and indexes.
  • Took regularly logical backups (export and import).
Technologies: Oracle DBA

Reports Automation Project

The project task was to provide sales and receiving reports for a US-based client for the purpose of in-house auditing for that financial year.

The project was completed using Pentaho ETL deployed in a Linux machine. This ETL had multiple parameter inputs based on which, the output files would be different. This ETL internally calls a reporting plugin to generate the report. The reporting plugin runs the report file and generates the report in the specified hard drive or emails the report to the specified recipients. I designed the whole architecture, developed, and deployed it.

Pentaho BI Project

Completed a whole BI project successfully right from deploying and configuring the Pentaho BI Server to SQL coding, designing, and scheduling reports for the stakeholders. The tools used were PostgreSQL, MySQL, Pentaho Data Integration, Pentaho Report Designer, and Pentaho BI Server.

Analytics on Big Data Sets in AWS

I analyzed the raw data files from a customer. The data size was in terabytes and I used AWS Redshift to get a solution. I designed and deployed Pentaho ETL in an AWS EC2 machine. Pentaho ETL executes the commands to Redshift and S3 in a preferred work flow for the desired output. The output files or data mart is used by the clients for marketing strategies.
2006 - 2010

Bachelor of Technology in Computer Science

Cochin University of Science and Technology - Kottayam, India

Languages

SQL, JavaScript, Snowflake

Paradigms

Business Intelligence (BI)

Storage

Redshift, Amazon S3 (AWS S3), PostgreSQL, Oracle DBA, Microsoft SQL Server, Teradata

Other

Pentaho Reports, Data Visualization, Dashboards, Data Analysis, Data Analytics, Data Processing Automation, iDashboards, Dashboard Design

Tools

Pentaho Data Integration (Kettle), Looker, Sisense

Platforms

Pentaho, Windows, Linux, Amazon EC2, Amazon Web Services (AWS)

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