Ryan Miller is proud of “Ooh La La,” the new album from his long-running rock band, Guster. He’s excited at the prospect of Guster’s concert this weekend at the Shelburne Museum, not far from Miller’s home in Williston.

Recording albums and playing concerts are, of course, what Guster does. “Ooh La La” is the band’s ninth studio album. The Shelburne concert will be the latest of a couple thousand shows Guster has played since forming more than three decades ago.

Miller is, however, taking on one big project unlike any he’s done before. He’s writing the music and lyrics for an off-Broadway musical based on the 2012 film “Safety Not Guaranteed” that will open in previews in September at the Brooklyn Academy of Music (BAM). Miller wrote the soundtrack for that movie and has followed with more than a dozen film scores. But a musical? That’s uncharted territory.

Miller called himself a “51-year-old dude/neophyte” in the world of New York musicals who doesn’t fully know what he’s doing as he works with seasoned Broadway and off-Broadway veterans. He said he’s had nightmares about the musical failing. He likes to stretch himself for projects that keep him occupied for weeks or months at a time, but a musical that might take years to fully develop sounds daunting.

And exciting.

“It’s a fascinating process,” Miller said. “I am just learning so much in real time.”

The flow of ‘Ooh La La’

Miller spoke June 21 with the Burlington Free Press on his houseboat on Lake Champlain. If a houseboat sounds like another case of rock-star excess, know that it’s a 57-year-old houseboat Miller bought with three friends for $3,000. It’s also more house than boat; like most abodes, it is incapable of locomotion.

The scruffy floating retreat fits Miller’s persona to a T. For his chat with the Free Press, he wore a cartoonish T-shirt touting the Hudson Valley, flannel pants festooned with floral prints and vibrant socks bearing the logo for the soft drink Topo Chico. His hair maintained its perpetually tousled status.

Nothing about Guster is so haphazard. “Ooh La La,” which came out May 17, is a meticulous-sounding record, brimming with brightly toned tunes with soft edges of melancholy. Miller said the lyrics reflect his own experiences but ideally bypass the “hyper-personal” to let the listener in on his perspective.

Miller, who’s married with two teenagers, has heard from fans who say it’s amazing that Guster can still relate to where they are in life after three decades.

“When that happens, that has something to do with why we’ve been able to maintain our place” of popularity with fans, Miller said, noting that the band sold out the famed Ryman Auditorium in Nashville in one day and the Red Rocks Park & Amphitheatre outside Denver in three days. “I do think we are in conversation with people.”

“Ooh La La” is a very Vermont-y record, and not just because Miller and bandmate Luke Reynolds, an Addison County native, live in Vermont. Grammy-winner Rich Costey, a Waterbury native, mixed, co-engineered and co-produced the songs “When We Were Stars” and “All Day.” University of Vermont graduate Peter Katis mixed most of the album’s songs and played keyboards. Part of the album was recorded in southern Vermont at Guilford Sound.

The Shelburne Museum performance will be very Vermont-y as well. “Let’s go full Vermont as much as possible,” Miller said of his approach to the concert.

Guster will be joined onstage by James Kochalka Superstar, the Burlington band led by the big personality of the vocalist/cartoonist, and the Zeno Mountain Band from Zeno Mountain Farm in Lincoln that supports people with disabilities. Miller is counting on nice weather as opposed to last summer, when Guster’s plans to perform on the Shelburne Museum lawn were continually washed out.

“We need to go back to the scene of the crime,” he joked.

Music for “Safety Not Guaranteed’

Miller will spend much of the summer cramming to get “Safety Not Guaranteed” ready for its BAM run from Sept. 17-Oct. 20. He became involved with the film a dozen years ago after striking up a friendship with Colin Trevorrow, the director of that time-travel-themed movie who at the time lived in Burlington. (Trevorrow, a Guster fan who would go on to direct films including “Jurassic World,” now lives in London.) That well-received film and score launched Miller’s career in writing music for movies, most recently for the Ilana Glazer comedy “Babes,” which came out the same day as “Ooh La La.”

Another Guster fan, Nick Blaemire, approached Miller with the idea of contributing music for a stage version of “Safety Not Guaranteed.” “My answer was, ‘Sure,’” Miller said, though he had no real idea what writing the songs for a musical might entail.

He traveled to New York and found that Blaemire, who’s writing the book for “Safety Not Guaranteed,” assembled several Broadway and off-Broadway actors and a guitar player to present a version of the production with Guster songs as placeholders. Miller said he was impressed by the narrative of the story but didn’t want “Safety Not Guaranteed” to be a jukebox musical framed by Guster songs, so he chose to write more than an hour’s worth of original songs for the production.

Miller said he’ll work on a film soundtrack for four to 12 weeks, but a multi-year musical is a different animal for someone who likes to take on a variety of projects. “I respect the medium,” he said, “but it’s not my workflow.”

He’s getting into the flow now as “Safety Not Guaranteed” makes its way to BAM’s 875-capacity Harvey Theater. Miller would like to see the show move to Broadway one day. “We’re not trying to be done with it at BAM,” he said.

“Safety Not Guaranteed” has already influenced Miller’s work with Guster. He said the band’s recent “We Also Have Eras” tour, which told the story of Guster in a theatrical-styled musical performance, was shaped in part by the work he’s doing on “Safety Not Guaranteed.”

“I almost felt like maybe we’re more of an art project than a band,” Miller said. “This sort of theater experience I’m having will remain conversant with the band.”

His work on film scoring, off-Broadway shows and presenting “super-special” shows with Guster “gets kind of gooey,” blending in one creative pot, according to Miller.

“It helps me to recontextualize what the band can be,” he said.

If you go

WHAT: Guster with James Kochalka Superstar and the Zeno Mountain Band

WHEN: 6 p.m. Saturday, June 29

WHERE: Shelburne Museum

INFORMATION: $55 in advance, $59 day of show; free for children 12 and under. www.highergroundmusic.com

Contact Brent Hallenbeck at bhallenbeck@freepressmedia.com.