He wrote about the circa-1840 building in a widely-shared piece in the Times.
There's now a separate article about No. 64 at Places, the journal of public scholarship on the built environment.
Hajdu writes:
From the first wave of immigration from Europe to lower Manhattan, through the rise of the Beats and avant-garde performance art in the mid-20th century, to the gentrification of recent years, the same building on East 7th Street has encapsulated one era after another after another.
Past occupants of 64 E. Seventh St. include:
• The parsonage for St. Mark's Evangelical Lutheran Church
• The newspaper Russky Golos ("Russian Voice")
• The Les Deux Megots coffeehouse, whose readings featured Allen Ginsberg, Paul Blackburn and Carol Berge
• The Paradox, taking claim to be the world's first macrobiotic restaurant where both Yoko Ono and folksinger Loudon Wainwright III worked
• Books 'N Things
• Tokio 7 (moved across the street)
Both articles are related to the world premiere of The Parsonage, a recorded album about the history of 64 E. Seventh St. Hadju and a group of musicians will perform live on April 27 at the Museum of the City of New York.
Per the MCNY site:
The Parsonage, which takes from the worlds of jazz, classical, and "post-classical" music, makes its debut on April 7 from Sunnyside Records. The song cycle features libretto by cultural historian David Hajdu and music by eight composers: Darcy James Argue, Theo Bleckmann, Regina Carter, Ted Hearne, Kirk Nurock, Renee Rosnes, Sarah Kirkland Snider and Dan Tepfer.