Gliffy, the web-based diagram creation and editing utility, has been rewritten in HTML5, allowing its developer to add a slew of new features, including support for Microsoft Visio as well as Google Drive cloud storage.

Chris Kohlhardt, chief executive of Gliffy, said the shift from Flash to HTML5 was "highly risky," but something that the developers have seen as necessary for the last two years to improve performance. Gliffy is actually live in both Flash as well as HTML5, but given the large number of HTML5-compliant browsers available, the Flash version is quickly losing relevance.

Rewriting Gliffy in HTML5 aligned the online utility with modern standards, Kohlhardt said. Customers who have signed up for Gliffy Online, its software-as-a-service platform, can now store their files inside Google Drive, using a variety of formats, including SVG, GXML, and JPEG.

Gliffy is one of a small ecosystem of app providers working within collaboration platforms like Atlassian and Microsoft Office. The company provides tools to quickly create diagrams and flowcharts that can be added to wikis and other documents. Gliffy makes money by convincing customers, such as those who write manuals and other documentation, to store diagrams online and create embeddable diagrams within electronic documents that can be dynamically updated.

One of the company's chief competitors is Microsoft, whose Visio flowchart software competes directly with Gliffy. With the new release, Gliffy now "speaks" Visio, and users can open, edit, and save documents in the Visio file format.

The new release also adds features such as the ability to drag and drop images, and coherent themes that can be extended across a diagram or flowchart as a whole.

Last year, Kohlhardt outlined the hazards of rewriting an established code base into a new language. The upshot, he said, was that the code, in whatever form, is assumed to work. Rewriting it simply adds new bugs. Nevertheless, he and his other developers took on the task to bring Gliffy up to speed with other sites being rewritten in HTML5, and it looks like it's paid off.