Ghassan Hallaq, Software Developer in Montreal, QC, Canada
Ghassan Hallaq

Software Developer in Montreal, QC, Canada

Member since May 16, 2019
Ghassan is senior solution architect with over 20 years of experience at companies like CN, Morgan Stanley, and TD Bank. He has also architected a lot of big data solutions, and he is an expert in applying AI and machine learning in his solutions.
Ghassan is now available for hire


  • Pillar Base, Inc.
    Serverless, AWS Lambda, DynamoDB, Cognito, Spark SQL, TypeScript...
  • ReactiveCore
    Scala, Akka, Golang, AWS EKS, AWS Glue, Kafka, Spark, Kubernetes, Istio...
    Python, Apache Airflow, Docker, CircleCI, Docker Compose



Montreal, QC, Canada



Preferred Environment

Linux, VS Code, IntelliJ, PyCharm, Jupyter,

The most amazing...

...project I've worked on used DL, NLP, and ontology to build an NLU model.


  • Senior Solution Architect

    2019 - PRESENT
    Pillar Base, Inc.
    • Developed an application to denormalize data from the relational database and stream it to an AWS Dynamo DB single table.
    • Worked on a proof of concept (POC) to assess the performance between Apache Spark SQL, Presto DB, and Apache Drill, with parquet files.
    • Built a data warehouse on AWS using Redshift and Redshift Spectrum.
    • Architected and developed an integration solution solutions based on AWS Lambda, API Gateway, Cognito, WMS, Facebook Graph API, Google Ads API, BigCommerce, Dynamo DB, and JavaScript/TypeScript.
    Technologies: Serverless, AWS Lambda, DynamoDB, Cognito, Spark SQL, TypeScript, BigCommerce API
  • Senior Scala Developer

    2019 - 2020
    • Architected and developed a solution to implement a worker thread pattern integrated with Apache Kafka.
    • Rearchitected the microservices components to implement the service mesh (Istio) in Kubernetes over the AWS EKS cluster.
    • Built a real-time streaming solution on AWS using Kinesis and AWS Glue. Developed a data model.
    • Implemented Apache Spark streaming with Apache Kafka to support the data model.
    • Integrated Apache Druid with Apache Kafka to implement time-series analytics on the AWS EKS cluster.
    Technologies: Scala, Akka, Golang, AWS EKS, AWS Glue, Kafka, Spark, Kubernetes, Istio, Node.js, React, AWS Kinesis
  • Senior Data Engineer

    2019 - 2019
    • Developed and optimized the Apache Airflow graph solution to support the data model.
    • Packaged the solution using Docker and Docker Compose.
    • Built a workflow in CircleCI to automate the building, packaging, and deploying processes.
    • Developed a big data ETL solution on Azure Cloud, based on DataFactory and integrated with Data Lake Analytics.
    Technologies: Python, Apache Airflow, Docker, CircleCI, Docker Compose
  • Senior Solution Architect

    2019 - 2019
    CN Railway
    • Built real-time and batch processing ETL solutions based on the DataFactory.
    • Architected and developed an event-driven application using Node.js, React, and GraphQL using Serverless tech.
    • Architect and build an integration solution using Apache Kafka on the AWS EKS cluster with Azure Power BI.
    • Designed a solution based on React and Node.js and deployed the solution using Docker and Kubernetes.
    • Architect and develop a solution to stream the data into the data warehouse on Azure.
    • Engineered interactive dashboards using Power BI with a data warehouse.
    Technologies: Java, Scala, Python, AWS EMR/EKS/Kinese, Apache Kafka, Apache Spark, React, Node.js, Kubernetes
  • Big Data Architect

    2016 - 2019
    Morgan Stanley
    • Architected and developed a big data ETL solution based on AWS EMR and AWS Kinesis.
    • Worked on building a knowledge graph using a triple store database and Elasticsearch.
    • Created a data streaming solution using S3, Lambda functions, AWS Kinesis data streaming, and AWS EMR service.
    • Helped on developing an NLP solution to enhance/enrich the features in the market data reports as a data analyst.
    • Built a data interactive UI based on React and React D3 integrated with Azure Power BI.
    • Developed a search engine for market data integrated with Elasticsearch and Apache Solr.
    • Worked on a POC to compare the latency between C++ and Golang.
    Technologies: Scala, Java, Golang, Python, Node.js, AWS Kinesis, React, NLP, DL, ML, AWS EMR
  • Big Data Developer

    2016 - 2016
    TD Bank
    • Developed a solution to three ETL big data projects using Apache Hive and Oozie.
    • Worked as part of the team on extending Hadoop security functionality.
    • Architected and developed a multi-threaded Java application to integrate a Linux local account with the Active directory, business requirement analysis, and sketching technical solution.
    • Received “Act for Impact Award” on my work.
    Technologies: Java, Scala, Golang, Hadoop, Spark, Streaming
  • Lead Software Engineer

    2014 - 2015
    NetBridge Consulting
    • Architected and developed two big data ETL applications based on Apache Spark, AKKA, Kafka, and Cassandra.
    • Built an application based on test-driven development (TDD).
    Technologies: Apache Spark, Scala, Kafka, Apache Cassandra, Java 8
  • Senior Software Engineer

    2011 - 2014
    Lebanon Consultant
    • Built and introduced big data practices.
    • Architected and built an ERP solution.
    • Spearheaded an integration solution.
    Technologies: Big Data, Scala, AKKA, Java
  • Senior Solution Architect

    2005 - 2011
    Accad Institute
    • Gathered the software developers' team.
    • Architected and developed the institute management solution.
    • Built a solution to automate the sugar factory.
    • Created a solution for a utility company.
    Technologies: Java, Oracle, WebLogic


  • Act for Impact Award (Other amazing things)

    Awarded for my work on a security project.


  • Languages

    SQL, Snowflake, Scala, Python 3, Java 8, JavaScript, C++, C, Go, TypeScript, R
  • Frameworks

    Serverless Framework, Presto DB, Hadoop, Apache Spark, Apache Camel, Express.js
  • Libraries/APIs

    Pandas, Facebook Open Graph API, React, REST APIs, PySpark, Node.js, BigCommerce API, Google Ads API, OpenCV, TensorFlow, Keras, PyTorch
  • Tools

    Apache Solr, AWS Glue, AWS Athena, AWS Quicksight, AWS CloudFormation, Auth0, Apache Airflow, Flink, Kafka Streams, Envoy Proxy, Istio, Microsoft Power BI, SMART on FHIR, Apache NiFi
  • Paradigms

    Serverless Architecture, ETL, Database Design, ETL Implementation & Design, Functional Programming, Fast Healthcare Interoperability Resources (FHIR), HL7 FHIR Standard, Agile Software Development, DevOps
  • Platforms

    AWS Lambda, Linux, Apache Kafka, Apache Flink, Docker, Kubernetes, iOS, Amazon Web Services (AWS), Azure
  • Storage

    AWS DynamoDB, Elasticsearch, MongoDB, Redshift, PostgreSQL, NoSQL, Graph Databases, MySQL/MariaDB
  • Other

    Data Analysis, Common Data Service, Data Warehousing, Serverless, ETL Development, Big Data Architect, Data Engineering, Data Architecture, Pyspark, Data Engineer, Software Architecture, SOA Architecture, Service Meshes, Architecture, Solution Architecture, HL7, CRM Design


  • Diploma in Computer Systems Analyst
    1994 - 1996
    Accad Institute - Aleppo, Syria
  • Progress towards a bachelor's degree in Mathematics and Physics
    1987 - 1990
    Aleppo University - Aleppo, Syria


  • Manager of Quality/Organizational Excellence
    OCTOBER 2011 - DECEMBER 2014
    American Society for Quality
  • Quality Engineer
    JUNE 2011 - JUNE 2014
    American Society for Quality
  • HACCP Auditor
    MARCH 2011 - JUNE 2014
    American Society for Quality
  • Six Sigma Black Belt
    JUNE 2010 - JUNE 2013
    American Society for Quality
  • Quality Auditor
    DECEMBER 2009 - DECEMBER 2012
    American Society for Quality
  • Project Management Professional
    Project Management Institute
  • Sun Certified Business Component Developer
    Sun Certification
  • System Administrator/Messaging
    JUNE 2005 - PRESENT
  • Sun Certified Web Component Developer
    APRIL 2004 - PRESENT
    Sun Certification
  • Level I Certification
    Linux Professional Institute
  • Microsoft Certified Trainer
    JANUARY 2004 - JANUARY 2014
  • System Administrator
    JUNE 2003 - PRESENT
  • Sun Certified Developer
    MARCH 2003 - PRESENT
    Sun Certification
  • Oracle 9i Database Administrator Certified Professional
  • Oracle 9i Database Administrator Certified Associate
  • Cisco Certified Design Associate - CCDA
    MARCH 2002 - MARCH 2004
    Cisco Career Certification
  • Cisco Certified Network Associate - CCNA
    DECEMBER 2001 - DECEMBER 2003
    Cisco Career Certification
  • Sun Certified Programmer
    Sun Certification
  • Professional System Engineer
    APRIL 2001 - PRESENT
  • Network+
    CompTIA Certification Program
  • A+
    CompTIA Certification Program

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