Change is afoot at eateries along the west side of Witherspoon Street. The expansion of House of Cupcakes into the vacant former Ferry House, a new look for portions of the Alchemist & Barrister, and targeted late May or early June opening date for Mamoun’s Falafel in the former home of Princeton Mattress are among the improvements, openings, and alterations planned.

Behind the Alchemist & Barrister on Palmer Square, Teresa’s Caffe is installing outdoor seating. Accommodating eight to ten tables, the patio will open June 15. At 66 Witherspoon Street, the restaurant Mistral is enclosing its patio dining area by adding a roof and an outdoor fireplace. The projected opening for that space is the first week in May.

More imminent is the opening of Cafe Vienna, a European-style venue specializing in traditional Viennese cakes and coffees, across town at 200 Nassau Street, former home of The Piccadilly clothing shop. Owner Anita Waldenberger said Tuesday that she is expecting to have a certificate of occupancy “within a couple of days.” Originally projected to open last January, the cafe has been delayed due to winter weather, construction, and permits. “But the countdown is on,” she said.

It was only a month ago that a fire broke out in the basement of the House of Cupcakes at 30 Witherspoon Street, temporarily displacing residents of apartments upstairs and closing the bakery. But instead of derailing the business, the blaze has provided an opportunity for expansion. Owners Ron and Ruthie Bzdewka plan to reopen in the space that housed the Ferry House restaurant until it shut down last year. The space is directly next door and twice the size of the bakery.

“We were going back and forth, and weren’t sure if we were going to make the move,” Mr. Bzdewka said this week. “It’s double the size and a lot more rent. But I guess somebody upstairs made the decision for us.”

The added space allows the couple to expand their line. Mr. Bzdewka said he wasn’t ready to reveal exactly what the additions to the line will entail. “We’re still waiting for approval from the town. But I will say that we want to bring some things that are not in Princeton currently.” The bakery specializes in a variety of flavors of cupcakes, baking all on the premises.

While the former space had space for six to eight people to sit at a counter, the new location will allow several tables and chairs. “That alone will be a tremendous boost for us,” Mr. Bzdewka added. “And it’s a much better layout. It’s wider, not like a bowling alley as in the old place.”

House of Cupcakes opened in 2008 and has since branched out to include two corporate franchise stores in East Brunswick and the Bronx. Two more are planned in Wayne and Clifton. Depending on obtaining needed permits, the Bzdewkas hope to be installed at their new location in Princeton within a month or so with “a huge grand opening,” Mr. Bzdewka said.

On the other side of the shuttered House of Cupcakes store is The Alchemist & Barrister restaurant and pub, better known as the A&B. To mark its 40th anniversary, the restaurant is planning a major renovation that will include a revamped exterior, redesigned dining room, and additional bar.

“Our space won’t be getting any bigger, but the two front dining rooms, which really don’t have much personality, will be changed,” said Tom Yermack, the restaurant’s office manager. “Those two rooms facing Witherspoon will become one room, and we’ll build a big bar right in the middle. That will allow 50 taps of beer. We currently only have eight taps in the pub, but over the last five to ten years microbrews have become huge and we want to take advantage of that.”

Between May and December of last year, the A&B renovated its basement, removing walls to change three separate rooms into one large space. “It was all knocked down to ground zero, and now it’s one big room with a giant beer walk-in, which will support the bar that will be directly upstairs,” Mr. Yermack said.

From the outside, changes to the A&B will include two large sets of windows on the Witherspoon Street side of the restaurant. On the alley where the current entrance is located, the dining room windows will be replaced by three sets of French doors. A performance area for musical entertainment will be built into the new space, said Mr. Yermack, who in addition to his restaurant duties is a musician and member of The Blue Meanies group.

The pub and patio will stay the same. “They seem to be the most popular areas of the A&B, and we’re trying to recreate that feel with the new bar,” he added. “It will be a new, more homey place. The dining room now doesn’t have much character, and we want to change that.”