Tech startup Toast will more than double the size headquarters in the Fenway’s Landmark Center with plans to hire an additional 250 employees this year.

Founded in 2013, the company provides tech platforms, including mobile point-of-sale systems for restaurants. It moved into Samuels & Assoc.’s Landmark Center in mid-2015. Toast’s office space will expand from 37,500 square feet to 81,000 square feet.

“From our founding as a three-person team in a basement to our expansive growth in Landmark Center, we’ve remained unwavering in delivering the best customer service and restaurant POS system built for restaurant success. Clearly, this commitment has resonated with leading brands across all 50 states,” Toast CEO Chris Comparato said in a statement.

Toast’s expansion comes as Samuels & Assoc. contemplates changes to the Park Drive complex’s outdoor spaces and a 3-year-old redevelopment plan.

Samuels recently submitted plans to the Boston Planning and Development Agency to build a 1.1-acre green and replace surface parking at the corner of Park Drive and Brookline Avenue. The land has been owned by the city of Boston since the 1940s, and Samuels & Assoc. has applied to the BDPA to acquire the parcel for a demonstration project. Among the allowed uses would be live performances, public art displays, food trucks, outdoor markets and up to 1,200 square feet of permanent structures.

“We’re taking a big expanse of pavement and turning it into a greenway,” said Peter Sougarides, a principal at Samuels & Assoc. “It gives Park Drive the parkway feel that was always intended when (landscape architect) Frederick Law Olmsted designed it over 100 years ago.”

Completion of the park is estimated in mid-2018.

Samuels & Assoc. is also preparing to submit revisions to the redevelopment plan for the 1.5-million-square-foot office and retail complex. The original plan, approved in 2014, called for demolition of the parking garage and construction of underground parking to make way for 550 apartments in three buildings and 185,000 square feet of retail space.

Because of physical and technical challenges, the garage will be retained, Sougarides said, and the master plan is being reconfigured by Elkus Manfredi Architects.

The Landmark Center was originally built as a Sears warehouse before being converted into office space. Samuels acquired the property in 2011.