It was a celebration on Fourth Avenue in Sunset Park as community leaders and elected officials along with students from P.S. 1 cut the ribbon on a brand new branch of the Brooklyn Public Library.

It's a unique project that also includes 49 units of affordable housing.

"It's the first of its kind in New York City to combine 100% affordable housing over a new 21st century library," said Michelle de la Uz, executive director of Fifth Avenue Committee, which partnered with the Brooklyn Public Library on the project. 

Fifth Avenue Committee is a nonprofit community development corporation that builds and manages affordable housing. The plan has been in the works since 2016, and required demolition of the existing 1970s-era library building at the site.

"We decided to contribute the land in partnership with Fifth Avenue Committee to demolish the existing library to build a library that's almost twice the size of the original one, and to create affordable housing in a community where there hadn't been any affordable housing built in 20 years," said Linda Johnson, president and CEO of the Brooklyn Public Library.  

The library features areas for adults, kids, and the largest dedicated space for teens of any library in the borough. It even has a recording studio. 

Upstairs there is over 50,000 square feet of residential space. Half of the apartments are studios and one-bedroom units, and the other half are two- and three-bedroom units. 

There's also a roof deck and some amazing views of the city. 

More than 60,000 people applied to live in one of the 49 units, including Miguelina Minier, who said she and her son were the first to move in.  

"I applied for so many apartments, in East New York, Queens, whatever matches my income, so I got called on this one, and it's so good, feels good," said Minier, who added that the library will be a second home for her and her son.  

Officials hope this won't be the only such partnership, but it isn't an easy process.

"It takes political will and it also sort of requires the perfect convergence of circumstances: a library that needs repair, a neighborhood that has the right zoning, but we are on the lookout for other projects," Johnson said. 

As de la Uz said, the need for affordable housing is absolutely off the charts, but so is the need for spaces like the library that are hubs for the community.