Case Study: CHAMP Success Story
March 6, 2026CMS Saves $1.4 Million Annually Migrating CROWD to AWS Cloud
Modernizing a 40-year-old mainframe-based system to deliver 97% cost savings and enhanced user experience
Executive Summary
The Centers for Medicare & Medicaid Services (CMS) has successfully migrated the Contractor Reporting of Operational and Workload Data (CROWD) application, previously a CMS Mainframe-based Model 204 (M204) Database Management System (DBMS), to CMS Amazon Web Services (AWS) Cloud.
The modernized "next-gen" CROWD 2.0 application, hosted in the CMS AWS enclave utilizing CMS shared services provides a reliable, scalable, cost-effective solution to monitor the performance of each contractor, Medicare Administrative Contractor (MAC) and others to process claims efficiently. The system contains workload data submission and reporting capabilities that allow the use of data for estimating budgets, defining operating problems, comparing performance among contractors, and determining regional and national workload trends. CROWD 2.0 features a modern Angular front-end user interface hosted in the CMS Enterprise Portal Services (EPS), authenticated, and authorized by CMS Identity Management System (IDM), a serverless architecture, and integrated with CMS MicroStrategy (MSTR) for reporting.
This migration paved the way for CMS to retire the M204 system in January 2025, transitioning to an efficient application in the CMS AWS cloud saving more than $1.4M in annual proprietary mainframe licensing costs. The application is projected to return a 97% annual cost saving rate to CMS's investment in the AWS cloud platform. The modular backend consists of 7 Application Programming Interfaces (APIs) in the Amazon API Gateway, backed by 16 Python based AWS lambda functions that facilitate the user's interaction with the solution. The application uses CI/CD pipelines that deliver code with code quality and security scanning built-in and enforce a minimum test coverage threshold of 85% for code deployment. The CROWD end-user community has provided positive feedback on their user experience in the user support sessions we have conducted since go-live that are highlighted in the testimonials section.
97%
Annual Cost Savings
$1.4M
Licensing Cost Reduction
85%
Test Coverage Threshold
Challenge: Cloud Migration of a Mission-Critical National Application
The legacy M204 CROWD system, over 40 years old, is one of the last monolithic M204 database systems in the CMS mainframe. It evolved through multiple changes over time and struggled with high licensing costs, limited user experience, and dated documentation. Compounding this challenge was an aggressive timeline to develop the new system, within scope and budget, so that the M204 system could be retired from the CMS mainframe before the end of 2024. Additionally, the system had to meet all of CMS OIT's rigorous requirements, from presenting a Business Case for modernization to obtaining its Authority to Operate (ATO) with the CMS technical landscape.
Solution
Working in close collaboration with CMS, Index Analytics led the seamless transition to the new web-based CROWD 2.0 application, resulting in significant administrative savings that will continue to benefit CMS for years to come. We elaborate on several key factors that were crucial to the successful implementation of CROWD 2.0 in the sub-sections below.
(a) Guiding Principles
Following Agile, Human Centered Design (HCD) and DevSecOps guiding principles, we focused on a minimum viable product (MVP) for CROWD 2.0 that we could quickly implement, iterate, and improve continuously. Our team developed and tested code in two-week sprints, with infrastructure deployment, application development, and testing occurring with over-lapping dependencies. Our user interface designers and architects worked closely with CMS and shared service teams, creating wireframes to improve the authorized user's experience within the application and navigate seamlessly to CMS MicroStrategy shared service, without reauthentication, using HCD principles. We staffed our delivery team as a fully empowered DevSecOps unit with developers, testers, operations, infrastructure, security and help desk personnel working as one team. With this strategy, we were able to achieve a secure, code-stable, working prototype within 4 months of project inception. A lean staffing model, a CI/CD code delivery pipeline with security scanning, and an 85% test coverage threshold built-in resulted in identifying bugs faster so that they could be resolved in a timely fashion. Our testing team worked with the CMS 508 teams to ensure that the CROWD 2.0 user interface met 100% compliance with CMS accessibility standards. Post go-live, since November 2024, our lean email helpdesk received 110 inquiries from the users, and 100% of the inquiries were resolved within 2 hours, surpassing industry standard help desk SLAs.
(b) Modern Technology Stack Hosted in CMS AWS
CROWD 2.0 utilizes cutting edge serverless technologies in the Cloud, such as an Aurora PostgreSQL serverless database, API gateway hosted APIs, and Python based lambda functions, to optimize cost and provide efficiency for the client. A fast-tracked implementation time and cost savings were also achieved by leveraging a variety of pre-existing CMS shared services and well architected frameworks to take advantage of existing vetted software and practices within the application, including authentication libraries, software security scanning tooling, software build tools, and enterprise portal hosting platforms.
CROWD 2.0 is implemented as a 3-tier application hosted in the CMS AWS Cloud. The primary AWS services utilized across the 3-tier solution stack are:
User Interface Tier:
- Static S3 site – Angular web application hosted in S3 rendered as a static site
Application Tier:
- AWS API Gateway – interfaces the user's UI actions with AWS lambda functions
- AWS Lambda using Python runtime – for backend orchestration of submitted data
- Amazon CloudFront – content distribution of the static site for performance efficient rendering for users across the continental United States
Data Tier:
- Aurora PostgreSQL Serverless Relational Database – for persistent transactional and reporting data storage
- AWS S3 – for batch file upload storage, and static website hosting
In addition to the AWS services and frameworks highlighted above, the application utilizes several CMS shared services, such as EPS for application tenancy, IDM for authentication/authorization, MSTR for reporting, Jenkins with Snyk/SonarQube for CI/CD pipelines, and Splunk for monitoring.
(c) Cost Optimization
During the implementation phase, we validated the serverless compute aspect of our Aurora PostgreSQL serverless database and the lambda-based backend data orchestration, which automatically scales to meet user demand especially during peak submission windows throughout the calendar year. For data submissions storage in S3, we implemented lifecycle policies that mode data to low-cost storage and purge based on business requirements. Since our end user-base which are the MACs and CMS that are distributed throughout the continental United States, we chose CloudFront, AWS's content distribution network (CDN) to provide better site performance via EDGE optimized regions. We also performed an AWS Well Architected Review (WAR) with the AWS team, validated our system architecture and processes, and incorporated their recommendations in phased enhancements.
We adopted a cost-conscious development mindset with the goal of providing the best ROI for our customers through monitoring, optimization, and transparency. We utilized an automation-first mindset with CloudFormation infrastructure-as-code (IaC), Jenkins CI/CD pipelines with built-in stages for code quality checks using SonarQube, pytest, jasmine and karma unit/integration testing framework, and security scanning using Snyk with every code merge and deployment. We also integrated Splunk ITSI for system monitoring and review the top five AWS service costs using Cost Explorer and CMS EAC tools. In addition, the CMS Cloud Products and Tools (CPT) contract team works with business owners to ensure cost transparency is maintained and aligned with the budget. This allows for transparent conversations with CMS on the AWS service costs to ensure we provide the best ROI to CMS for their cloud investment. CROWD 2.0 has been able to deliver a projected 97% annual application cost savings rate over the legacy mainframe application since go live.
Outcomes
The modernized, "next gen" CROWD application is reliable, scalable, cost effective, and hosted in the CMS AWS Cloud utilizing CMS shared services. It provides vastly improved user experience with a one-stop-shop interface that allows users to submit data, receive submission status dynamically, and seamlessly consume reports using a familiar UI-based interface. The product feature changes to the application are performed in an agile fashion, incrementally and continuously through CI/CD pipeline releases. CMS was able to successfully retire the current CMS Mainframe M204 mainframe application on schedule, resulting in savings of approximately $1.4M in annual proprietary licensing and storage costs at a projected 97% annual application cost savings rate. The CROWD end-user community has provided positive feedback on their user experience in the user support sessions we have conducted since go-live that are highlighted in the testimonials section.
Testimonials
Thank you all for being there for us throughout this process. It's clear that you’ve put in a tremendous amount of work, and we truly appreciate everything you've done. I’m confident that this will become a very successful project. While there have been some glitches here and there, that’s to be expected, and I’m sure these will be ironed out. Ultimately, this is shaping up to be a fantastic product, and you’ve all done an excellent job. Thank you once again!
I feel very confident! It'd be incredibly smooth going forward. I'm excited for next month.
Old CROWD didn't do all of what the new system is doing (talking about more extensive data validation to ensure Data Integrity built in the new CROWD). And I think that's wonderful. That's a big reason I'm so impressed. I mean a huge reason why. I know we're all impressed by how much you guys have just drilled down into something. Thank you very much.
I wanted to thank you once again for taking the time with me this morning as I navigate the best possible road forward to make this a success. I cannot state enough how appreciative I am that you found time in your very busy week to help. I hope you all have a wonderful weekend.
I want to express my sincere gratitude for all the help and support you've provided. It's been incredibly reassuring to have such prompt assistance, you've made it possible to address problems quickly and efficiently. I really appreciate your dedication and proactive approach.
Thank you to the Index Analytics team for all the helpdesk assistance you provided. Your support in addressing my questions and offering valuable information during the UAT stand-ups has been incredibly helpful. The assistance you've given has been truly useful, and I appreciate all your efforts. Thank you again!
Disclaimer: This communication does not represent the official views, policies, or positions of the Centers for Medicare & Medicaid Services (CMS) or the U.S. Department of Health and Human Services (HHS). References to CMS programs, systems, or activities are provided for informational purposes only and do not constitute endorsement, sponsorship, or approval by CMS or HHS of any products, services, vendors, or organizations mentioned. Any performance metrics, cost figures, or outcomes described are the responsibility of the authors and have not been independently validated by CMS.