The Brooklyn Development Group announced on Monday that it will be giving $400 million in a project to develop a $400-million, 5.1-acre site in the Williamsburg neighborhood that includes a major retail and office complex and the future headquarters of the city’s biggest tech company.

The Brooklyn-based company, which is led by developer Tony Reuben, has previously invested in development projects in Brooklyn including the $1.5 billion Williamsburg Bridge project, the $350 million development of a parking lot at the corner of Third Avenue and Avenue B, and the $300 million development at the intersection of Seventh Avenue and Bedford Avenue, which included the $225 million development last year of the new headquarters of a tech company called GoDaddy.

“This project is not only a first step toward a new Brooklyn, but it is a great example of how we can work together in an open and collaborative way to advance economic development, improve the health of our communities, and create a stronger and more sustainable economy,” said Brooklyn Development President Mark DeSantis in a statement.

The project will be called The Brooklyn Landing and is expected to be completed by the end of 2019.

The developer will be working with a team led by architect Chris Lattanzio, who has worked on projects in Atlanta, New York City, and New Jersey.

The company has already begun work on the site.

“The Brooklyn Landing is a natural next step for Brooklyn development and will further our efforts to make the city stronger and healthier,” said DeSantes in a release.

“I look forward to working with this team to create a truly great Brooklyn Landing that will transform this city for generations to come.”

The project is being led by Brooklyn-headquartered Brooklyn Development Partners.

The development will include office, retail, residential, and mixed use residential projects in an area that will be known as the Williams-LaGuardia Corridor.

The team will begin work on building in the area by the start of the 2020s, and plans to open a “super-tall” office tower, which will be similar to the tallest buildings in New York, later this year. 

According to the Brooklyn Development website, the project will include “a new, 1.6-acre parcel with nearly 1 million square feet of retail space, commercial and residential units, a park, an outdoor plaza and a new street, extending north to the river and east to the south.”

It will include a hotel, offices, offices and retail space for local restaurants and a mixed-use residential and retail development, as well as a park and plaza with public gardens.

The land was originally developed in the 1970s for an office tower that was later demolished and replaced by the new project. 

“The Williams-Laggett corridor is a highly desirable location for a new office tower because of its location on the edge of the borough and proximity to several major transit hubs, including the New York subway and Manhattan’s Fulton Ferry,” the company said in a press release. 

The Brooklyn-led development comes just months after Brooklyn developer Tony DeSantos proposed an entirely new development on the same parcel of land, the future site of a new shopping center, in a letter to the city.

The developers plans call for an 18-story, 300,000-square-foot retail and restaurant complex with a total of about 800,000 square feet, plus the development of an office building and retail complex on the land. 

 The project is expected for completion by the 2020 census.