Cloud

• Self-host Azure DevOps agent in AWS

• Setup OpenVPN log self-cleaning using cron job (crontab)

• Automated email sending with attachment via SES and S3 Event Notification

• Architected self-host/local deployment solution to launch our platform in customer's environment

• Created automated ticketing process to gain additional 4% (total 7%) cloud operation cost savings.

• Resolved issue with cookie to ensure same-site: lax doesn't break existing functionality.

• Moved Kubernetes pods from EKS Fargate to EKS Nodegroup for better performance and lower cost.

• Resolved issue with crashed pods without error message.

• Created CDK for AWS connection/integration.

• Created CLI for cloud connection using Python.

• Created a process to launch Cloudsaver on client's AWS commercial and GovCloud accounts.

• Automated shutting down and starting resources using AWS Lambda and Event Bridge.

• Setup multiple environment using EKS, MSK, Aurora, Elasticache Redis, OpenSearch, API Gateway, etc.

• Wrote custom OAuth 2.0 authorizer running on Lambda for API Gateway.

• Configured Ingress-Nginx controller with AWS NLB for EKS and Azure Load Balancer for AKS.

• Configured Glue crawler, Athena and Lambda for Operations team to query invoice data.

• Moved EMR Phoenix backend storage from S3 (EMRFS) to HDFS to improve query performance.

• Configured private connection to Elasticsearch cluster with VPC endpoint and private hosted zone.

• Workaround Micronaut OIDC configuration to enable authentication on AKHQ with Okta.

• Resolve intermittent Aurora RDS database crash.

• Dual-hosted CloudSaver front end app on Azure Static Web App and AWS EKS.

• Setup automatic wildcard subdomain routing for white labeling.

• Configured cross-region cross-account zero-code bridge from AWS Marketplace SNS to CloudSaver app using SNS, SQS, and EventBridge pipes.

• Processed Azure CUR data daily using Azure Functions and Azure Synapse Analytics with Spark pool.

• Remediated issues to meet CIS 1.4.0. for AWS Foundational Technical Review (FTR).

• Captured application logs in EKS Fargate to Datadog using sidecar instead of Datadog recommended way of using Lambda.

• Capture APM data and application logs in EKS Nodegroup using Datadog daemonset via unix socket.

• Correlated logs and traces in Datadog by formatting application logs as json.

• Refactored Docker image to run in both Lambda and ECS Fargate.

• Enabled/disabled CUR obfuscation flow using CloudWatch composite alarm.

• Updated CUR obfuscation process to use S3 event notification, SQS, and EMR serverless.

• Automated test file creation and upload using Lambda-backed CloudFormation custom resource when launching resources.

• Switched Transit Gateway to VPC peering to save data processing cost.

• Submitted dependencies and multiple python files to EMR serverless using both Python virtual environment and PySpark Native Features.

• Implemented cluster and application autoscaler for WordPress in ECS.

• Saved $10,000/month by removing redundancy on legacy application.

• Resolved Aurora MySQL issue due to deadlock caused by index creation.

• Configured pseudo blue/green deployment for API deployment in EKS.

• Saved $15,000/week by moving CUR ingestion from EKS Fargate to EKS Nodegroup in public subnet.

• Bypassed API Gateway 10 MB limit using CloudFront with Python (with pyJwt) custom authorizer running on Lambda@Edge.

DevOps

• Validated Pull Request source and destination branch to prevent unexpected Git merge in Azure DevOps.

• Automated comments in Azure DevOps Pull Request using service hooks and Azure Functions.

• Injected private key for custom authorization using jq and Azure DevOps secure files.

• Created Azure DevOps extension to move work items between swim lanes by using dropdown.

• Automated moving work items on completed Pull Request between Kanban board columns using Azure Functions.

• Setup Gated build PR to validate build before Git merge.

• Implemented GitOps to AWS with change set to prevent unintended change on production stacks.

• Optimized build time by building front and backend in parallel.

• Created dynamic Kubernetes workers deployment per Kafka topic using Helm, jq, and yq so workers can be scaled independently.

• Scheduled pipeline that automatically runs C# script (csx), commit, push, and create Pull Request.

Programming

• Created Cloudsaver CLI using Python, setuptools, and Click.

• Developed Visual Studio Extension to change the environment that local applications point to.

• Write scripts to export/import HBase snapshots.

• Wrote bash and PowerShell scripts to connect AWS accounts and Azure subscriptions to CloudSaver app.

• Applied schema migration using idempotent EF script export, S3 event, Lambdas, and SQS.

• Update Visual Studio Extension to encrypt/decrypt value with DialogWindow, ToolWindow, and WPF.

• Saved $7,000/week by refactoring .NET 7 application to run on Linux ECS container.

• Debugged running .NET 7 application using Visual Studio remote debugger.

• Developed a web page on CloudSaver app to enable self-configure SSO using React and ASP.NET Web API backend.

System

• Migrated OpenVPN configuration to new servers.

• Resolved OpenVPN issue where config failed validation but was saved and caused the web interface to be unreachable.

• Setup KEDA to enable pod scaling in Kubernetes (EKS) based on data from CloudWatch.

• Enabled monitoring of Kubernetes pods by injecting Dynatrace agents into CloudSaver pods.

• Troubleshot HBase/Phoenix error by using hbck to check for table inconsistencies.

• Configured Fargate logging to send application logs in Kubernetes (EKS) to CloudWatch Logs.

• Configured Jaeger to run in Kubernetes (EKS) in ECS Fargate with and without agent sidecar and OpenSearch as storage.

• Configured Amazon Container Insight using AWS Distro for Open Telemetry (ADOT) in EKS.

• Implemented auto memory dump usng Kubernetes preStop lifecycle.

• Configured application to export telemetry data directly to Jaeger collector removing the need for sidecar.

• Patched .NET 6 vulnerability that's no longer fixed using .NET 8 docker image and .NET 6 runtime.

• Bypassed CoreDNS 5s bug issue by routing pod-to-pod traffic through Ingress.

• Fixed issue with Docker Desktop used significant amount of memory.

Staffs

• Wrote script to simplified memory dump capture and upload to S3.

• Implemented an auto restart pipeline in ADO.

• Migrated OpenSearch indices to a different cluster using replication.

• Implemented cluster autoscaler on EKS Nodegroup.

• Captured application logs in EKS Nodegroup.

• Added container insights for EKS through add-on.

Various

• Assisted with answering technical questions at CloudSaver booth in AWS re:Invent 2022.

• Documentated various architecture and data flow diagrams using draw.io.

• Assisted in obtaining SOC 2, ISO 27001, and GDPR compliances.

Auth

• Setup SAML 2.0 for clients who use Okta, PingFederate, and Azure in Auth0.

• Fulfilled client security requirements by enabling Single Logout (SLO) between Auth0 and PingFederate.

• Updated from built-in authentication to OpenID and OAuth 2.0 using Auth0.

Big Data

• Significantly improved ingestion rate from Apache Spark to Apache Phoenix using Phoenix Spark connector.

• Wrote C# Apache Spark application running on EMR to reduce Cost and Usage (CUR) data.

• Launched Apache Phoenix and Apache HBase on EMR to serve invoice data to web application.

Cloud

• Significantly reduced timeout by migrating database from Amazon Aurora Serverless to Amazon Aurora RDS cluster.

• Setup WordPress using Bitnami Docker image hosted in ECS Fargate with EFS storage and Amazon Aurora serverless.

• Launched and configured OpenVPN Access Server.

• Moved WordPress from ECS Fargate to ECS EC2 to enable faster throughput by connecting it to NFS server backed by EBS.

• Moved Learning site to Amazon Lightsail due to storage limit in Azure Static Web App.

• Initialized ASP.NET session database in AWS RDS for SQL Server (web edition) to improve compatibility.

• Resolved issue with disabled AWS SES due to high email bounce rate.

• Re-configured AWS VPC network from VPC peerings to hub and spoke model using Transit Gateway.

• Setup Content Delivery Network (CDN) using Amazon CloudFront and S3.

• Created static website in Amazon S3 and Amazon CloudFront for Learning team.

• Automated copy and bootstrap of Aurora MySQL database to lower environment using EventBridge and Lambda.

• Ran Hangfire as ECS Service and added capability to launch ECS tasks.

• Adopted IaC by launching and importing resources using CloudFormation templates.

• Containerized and ran batch applications on ECS Fargate to improve scalability and reduce cost.

DevOps

• Containerized batch applications on deployment to Amazon ECR (Elastic Container Registry) using Docker.

• Created Azure Artifacts feed to host private Nuget packages.

• Utilized AWS CodeDeploy hooks to update running applications on EC2 by renaming files.

• Installed RDS Combined CA bundle to enable SSL to Aurora MySQL on various resources (Docker, EC2, etc.).

• Migrated source/version control from TFVC to Git.

Miscellaneous

• Initiated and led weekly team meeting.

• Initiated and led bi-weekly architecture meeting.

• Setup and maintained Microsoft SharePoint for department information sharing.

• Implemented Datadog APM for CloudSaver applications on EC2.

• Replaced Datadog with Dynatrace for CloudSaver applications on EC2 due to APM for .NET was not ready.

Programming

• Configured CloudSaver web application to use in proc session state to fix issue with incompatibility with Aurora MySQL.

• Upgraded batch applications from .NET 4.6.2 to .NET 5, containerized and run in ECS Fargate.

• Upgraded shared library from .NET 4.6.2 to .NET Standard 2.0.

• Created a simple web application using Node.js and VS Code to host temporary learning courses.

• Used Handlebar.NET to map database bootstrap script with data from AWS secrets manager.

• Decoupled shared code from batch applications by moving it to a Nuget package.

• Resolved issue with TLS 1.2 between newer Linux kernel and MySQL due to removed older cipher suites.

• Wrote EC2 rightsizing scripts requested by client in Bash and PowerShell.

Auth

• Built integration with Okta, Ping Identity, OneLogin to enable SAML 2.0 SSO.

• Moved custom Sustainsys SAML 2.0 logic from HttpModule to OWIN Middleware.

• Setup Microsoft Active Directory.

• Enabled Cloudsaver app to authenticate against Microsoft AD.

Cloud

• Programmatically installed and configured CloudWatch agent using AWS Systems Manager (SSM).

• Used AWS API Gateway and Lambda to provide endpoints to store metadata for CloudSaver bundling and compression engine.

• Automated Amazon EC2 virtualization type conversion from PV to HVM.

• Installed ENA module and NVMe driver programmatically via AWS System Manager (SSM) for Zen to Nitro conversion.

• Saved on SSL certificate cost by using AWS Certificate Manager (ACM).

• Designed and performed Amazon S3 Bundling PoC for client.

• Automated creation and sharing of AMI Golden Image with partner.

• Launched NAT Gateway to workaround Elastic IP (EIP) limit.

• Automated benchmarking of EC2 using Aida 64 and Geekbench on custom AMI.

• Configured Site-to-site VPN to client environment.

• Setup automatic security patching using AWS SSM Patch Manager.

• Setup automatic agents update using AWS SSM State Manager.

• Implemented EBS Safety Net feature using Amazon CloudWatch alarms and Amazon SNS.

Database

• Created SQL Server stored procedure with Table-Valued Parameters to generate complex reports.

• Improved EF batch insert performance by utilizing SqlBulkCopy.

• Enabled consistent database schema migrations using EF 6 (Entity Framework) Migrations.

• Moved Hangfire database from SQL Server to Amazon Aurora Serverless.

• Moved critical data from SQL Server to Amazon Aurora Serverless.

• Setup Amazon DocumentDB as a storage to store status and configuration for batch applications.

• Implemented Elasticsearch to store and improve query speed of client's AWS CUR/Invoice data.

DevOps

• Implemented CI/CD pipelines using Azure DevOps and AWS CodeDeploy with deployment to EC2 and Lambda.

• Designed and applied Azure DevOps building and deployment steps.

• Troubleshot phantom TFS workspace.

• Setup Kanban board, design and document development process in Azure DevOps.

Graphic

• Added emboss effect on CloudSaver logo using Adobe Illustrator.

• Edited promotional video using After Effect and Quick Time.

• Assisted in creating and editing of CloudSaver assessment instruction video using Movavi.

• Blurred sensitive information in CloudSaver instruction videos using Adobe Premier Element.

System

• Wrote code and scripts to automatically migrate EC2 in Xen hypervisor to Nitro-based hypervisor.

• Automated EBS cost saving by writing scripts to setup and move data to smaller EBS volumes.

• Map disk drives and partitions to EBS volumes using PowerShell and Shell script.

• Created mirror (Raid 1) on EBS using PowerShell and Diskpart.

• Created script to create, attach, initialize, part and format EBS volumes.

• Automated benchmarking by programmatically run AIDA64 on various EC2 using AWS Systems Manager (SSM).

• Hosted private Nuget server in EC2.

• Developed feature to bundle files and extract a single file by querying the byte range in S3.

• Wrote script to replace device name with UUID in fstab to migrate Amazon EC2 to Nitro-based instance type.

• Installed and renewed SSL certificates in IIS.

• Disabled deprecated SSL and TLS versions/protocols on Windows Servers via PowerShell.

• Disabled weak encryption protocols/cipher suites on Windows Servers.

• Configured OpenVPN access server to allow VPN connection to test account VPC.

• Wrote script to automatically fix Linux kernel update failure.

• Troubleshot URL Rewrite on IIS.

Programming

• Created .NET generic classes to simplify retrieving multiple metrics from CloudWatch.

• Created .NET extension methods to sort enumerables by attribute and property name using reflection.

• Implemented drag and drop report filter with level indentation.

• Added custom tooltip on HTML tables using Tooltipster.

• Created custom HTML tables with frozen top, bottom, and first column using CSS.

• Added custom scrollbar using mCustomScrollbar.

• Created various reports in PDF and Excel using TallPDF, EPPlus, and Highcharts.

• Implemented background process queueing and scheduling using Hangfire to decouple front end and back end.

• Created custom .NET attributes to improve code efficiency.

• Worked around template formatting bug in Salesforce CPQ by utilizing knowledge in Apache FOP.

• Developed ASP.NET Core Web API to compress file using LZMA and hosted it in Ubuntu using NGINX.

• Created .NET SDK for CloudSaver compression engine.

• Enabled OWIN on ASP.NET Web Forms.

• Enabled ASP.NET Session on OWIN.

• Solved race condition issue by implementing ServiceLocator pattern.

• Moved some appsettings to environment variable for easier management and security.

• Utilized TopShelf to install Hangfire as Windows Service.

• Improved page response by asynchronously loading batched data using custom queue written in JavaScript.

• Enabled CloudSaver web application to send email using Simple Mail Transfer Protocol (SMTP).

• Created a Razor page based internal web application to query New Relic API using GraphQL.

• Automated migration of previous generation Amazon EC2 with Xen hypervisor to newer AWS Nitro hypervisor

• Converted instances from PV (Paravirtual) to HVM (Hardware Virtual Machine)

• Installed NVMe driver and ENA (Enhance Network Adapter) module on the instance

• Fixed fstab for Linux

• Developed CloudSaver iOS app using Swift and XCode.

• Integrated SAML 2.0 SSO handling using Sustainsys/SAML2 library on CloudSaver web application for Okta, OneLogin and Ping Identity.