The space is bright and open, with high ceilings and large windows that highlight the eternally terrific people-watching of the Lower East Side. The mint corner location is the former home of an outpost of Serafina, a chain known for its wood-fired pizzas, which explains the enormous domed oven taking up a quarter of the dining room. The oven, with its colorful tiles is somewhat visually cacophonous, given the understated rusticity of the rest of the room. Glowy porcelain light fixtures, translucent white streaked with rivers of darkness, give the impression of the nacreous interiors of oyster shells, or molded slices of Gorgonzola. They’re the work of the artist Nicole Pilar, who also made the interestingly multi-textured, organic-shaped platters on which many of the courses at 63 Clinton are served. At Cactus Wren, these platters show up beneath the appetizer of fruits de mer, a dish appealingly sized for one, featuring a rotating selection of composed bites that on my visits included dressed raw oysters and clams, Jonah-crab claws, and a Gilda skewer of raw tuna and shiso leaf. Indeed, the restaurant strikes me as a perfect choice for solo dining: belly up to the bar for a glass from the strong wine list, which foregrounds small producers, and order something to nibble on, or dive into, or bask in. On one of my visits, I found myself seated next to a woman indulging, with exquisite poise, in a glass of wine, a book, and what seemed to be every single caviar dish on the menu. There’s a lesson there for us all: it’s important, sometimes, to do exactly what you want to do, and to let yourself enjoy it. ♦