Twenty Years of Pandoc

John MacFarlane released the first version of Pandoc on August 3, 2006, as a Haskell-based document converter supporting multiple formats like Markdown, HTML, and LaTeX. Over twenty years, the project evolved into the most popular Haskell program, now supporting over fifty document formats and integrated into major academic writing tools like Quarto and Jupyter Notebook. MacFarlane chose Haskell for its strength in parser design and built Pandoc around a more reliable abstract syntax tree architecture rather than regex-based transformations used by competing implementations.