Somewhere, Spike Lee’s smiling.

It appears that the Williamsburg exodus has begun — with apartment inventory shooting up by 25 percent and rent slipping back down to 2015 prices — thanks to the L train shutdown.

Local hipsters apparently are heading for the hills as the final day of service fast approaches.

“The shutdown is eight months away, which means that anyone who has to renew a lease is thinking twice,” explained Grant Long, senior economist at StreetEasy.

Furthermore, a “pre-shutdown shutdown” is set to begin on Aug. 11 — meaning service will be disrupted between Brooklyn and Manhattan for at least 15 weekends before the official closure even goes into effect.

Inventory is already up 25 percent since the same time last year, according to data compiled by StreetEasy.

In North Brooklyn, rents have slid to 2015 prices — and almost half of all apartment listings in Williamsburg are renting for less than they did two years ago on the site — with an average chop of $250.

New Yorkers first learned about the L train suspension in 2016, but Long says they didn’t start seeing major changes until after it came time for people to renew their leases for 2019, which is when the official 15-month shutdown is slated to begin.

Those who oppose gentrification in Brooklyn, such as Lee, will likely welcome the Williamsburg exodus with open arms. The filmmaker has been one of the most vocal critics in recent years and has unleashed a number of profanity-laced rants on the subject.

“Why does it take an influx of white New Yorkers … for the facilities to get better?” Lee once asked during an event at the Pratt Institute in 2014.

“What about the people who are renting? They can’t afford it anymore,” the director said. “People want to live in Fort Greene. People want to live in Clinton Hill. The Lower East Side. They move to Williamsburg. They can’t even afford f–kin’, mother—kin’ Williamsburg now because of the mother—kin’ hipsters.”

Thanks to the L train shutdown, though, things are finally changing.

In June, nearly a third of listed apartments across Williamsburg received a price cut — more than any other Brooklyn neighborhood, according to StreetEasy.

Landlords are also offering major incentives to folks who have been longtime renters and choose to stay in the neighborhood.

In June 2018, more than a quarter — 27 percent — of all Williamsburg apartments saw a price reduction, and 18 percent of the listings came with offers of free rent for a month or more.

Vittorio Faricelli, a Citi Habitats broker who was born and raised in North Brooklyn, told The Post that some buildings are offering as much as three months of free rent for those who sign an 18-month or two-year lease.

For example, the landlord of 50 N. 5th St. is offering three months free on 24-month leases, Faricelli said.

That means a two-bedroom, two-bathroom unit in the seven-story luxury building is now asking $4,419 a month.

The property includes 15,000 square feet of amenity space — from a two-story gym with yoga and boot camp class, to communal working space and free morning coffee in the lobby lounge. There’s also a billiards lounge, a screening room, an indoor basketball court, bocce ball, a landscaped courtyard and a rooftop with a dining area, BBQ grills and an outdoor shower.

The building, however, might want to update its marketing copy.

The StreetEasy listing notes: “Before you head out for the day, grab a complimentary fresh cup of coffee from the lobby lounge to sip on your way to the L train.”