In 2014 at the encouragement of the Smithsonian Transcription Center she began working on
Wikipedia; her first article, on botanist and collector
Charlotte Cortlandt Ellis, was quickly flagged for deletion.[2][11] She was spending at least two hours a day on Wikipedia,
Wikimedia Commons,[12]Wikidata,[13] and
iNaturalist,[14] and organised several volunteer events with Wikipedian
Mike Dickison.[8] Her Wikipedia work focussed on women in science, neglected scientific collectors, and the endemic moths of New Zealand.[2] Inspired by
Ahi Pepe Mothnet, her project to create articles on all 1,800 New Zealand endemic moth species draws on openly-licensed images from iNaturalist, the
Auckland Museum, and the
New Zealand Arthropod Collection.[1][3] She has been an advocate of open licenses for digital collections of museums and cultural institutions. She has also worked on creating Wikidata entries and Wikipedia articles for female scientific illustrators in the collection of the Biodiversity Heritage Library.[1][15]
Leachman has presented at
VALA,[16] New Zealand's National Digital Forum,[17] and WikiDataCon.[18] The Smithsonian invited her to be on the "Build the Crowdsourcing Community of Your Dreams" panel at
SXSW in 2016.[19] In 2018 she was awarded a travel scholarship to present at the WikiCite conference in
Berkeley, where she spoke about the difficulties of finding metadata on historical biodiversity literature.[20][21] In 2019 at Biodiversity Next in Leiden she spoke about using Bloodhound Tracker (now
Bionomia) to link museum specimen data to collectors.[22]
In 2019
Auckland Museum made Leachman a Companion of Auckland War Memorial Museum in recognition of her work with their openly-licensed digital collection images.[20] In 2023 Leachman was awarded the
Wikimedia Laureate award.[23]