-- The NIST HealthCare Standards Landscape (HCSL) is a project to develop and demonstrate a web-based repository of information (called "Landscape") on healthcare informatics standards and other related information. Users may navigate the HCSL web site, search and retrieve information about healthcare standards, about their development organization(s), about organizations adopting and using these standards, and other relevant healthcare standards' information. The HCSL was originally developed using an Oracle database on a Windows platform. To enable wider adoption of the HCSL application, it has also been implemented using open source software with PostgreSQL and MySQL databases on a Linux platform. This paper describes the software implementation and the lessons learned in porting to open source databases. The HCSL was built as a 3-tier web-based application providing user and content access controls. It may be adopted for other applications by modifying the software a...