Within the span of five days in January, Sean Wang’s life changed about as dramatically as is possible for a young filmmaker.

On Jan. 19, Wang’s “Nai Nai & Wài Pó,” a documentary short about his two grandmothers, was nominated for an Academy Award. On Jan. 23, his feature film debut, “Dìdi,” a coming-of-age tale drawn from Wang’s life growing up as the son of Taiwanese immigrants in Fremont, California, premiered at the Sundance Film Festival.

“Dìdi” was immediately hailed as the exciting debut of a new filmmaking voice. The film, a comic and sensitive tale about awkwardly finding yourself in the early digital days of MySpace and AOL Messenger, went on to win an audience award and a prize for its ensemble cast at Sundance. In “Dìdi,” a portrait of an artist as a young skater kid, Chris Wang (Izaac Wang) hesitantly becomes a “filmer” of his friends’ skating tricks, a path that mirrors Wang’s own first steps behind the camera.

In one scene, someone jokes that Chris, nicknamed “Wang Wang,” will later thank them in his Oscar speech — a prophecy that very nearly came true before “Dìdi” even opened in theaters. “Nai Nai & Wài Pó” ultimately didn’t win at the Oscars, though Wang’s grandmothers did earn “best dressed” from GQ.

“I’m sure people who saw the movie pre-Oscars and after Sundance were like ‘Oh my God,’ ” Wang says. “Now they’re like, ‘Well, it didn’t happen. Better luck next time, Wang Wang.’ ”

For Wang, 30, though, luck has had little to do with his swift rise, nor is he any kind of overnight sensation. “Dìdi,” being released in theaters July 26 by Focus Features, is what Wang has been steadily building toward, in skateboarding videos, YouTube uploads and short films since he first started filming himself attempting ollies.

“There was something about it that I loved,” said Wang in a recent interview. “It felt like Legos, in a way. You start with nothing, and by the end of it, you have something. And then you get to show your friends.”

Wang has carried on that mindset as a filmmaker, making collage- like movies both with and about his friends and family. His short “3,000 Miles” chronicled a year away from his parents with a soundtrack of voicemails left by his mom. In “H.A.G.S. (Have a Good Summer),” Wang, then in his mid-20s, called up old middle school classmates who had written in his yearbook to reflect on their past while pondering their unfolding adult lives.

“Dìdi,” similar in spirit to those shorts but more ambitiously narrative, is an effervescent amalgamation of fact and fiction. It was shot in Wang’s childhood home and old neighborhood. Chris’ mother is played in the film by Joan Chen, but the live-in grandmother is played by one of Wang’s real, GQ-certified grandmothers, Zhang Li Hua. On most days, Wang’s real mother was on set, too.

“The hope,” Wang says, “was always to keep it feeling very familial and homegrown and to have my real family become part of the process with my film family.”

In some ways, “Dìdi,” which is Mandarin for little brother, doesn’t differ radically from other coming-of-age films before it. “Stand by Me” is a touchstone for Wang. There are memorable, foul-mouthed fights with his older sister (Shirley Chen), shy encounters with girls and disappointments with best friends.

But Chris’ adolescence is also uniquely his. His quarrels with his mom stem in part from unsettled feelings about his still-forming identity. Wanting to fit in with a new group of skaters, Chris lies that he’s “half Asian.” He’s also told by a crush that he’s pretty cute “for an Asian.” With a light touch, “Dìdi” captures the experience of a first- generation kid navigating two worlds, plus one in between.

“I was really cognizant of not making a capital-I identity movie,” says Wang. “A lot of what I wanted to capture was the feeling this kid goes through about being a kid in America with immigrant parents. The hope was that all the themes in the movie about identity and race and adolescence are just felt and not necessarily commented on.”

For Chen, the actor- director of “The Last Emperor” and “Lust, Caution,” “Dìdi” hit home. Speaking from Atlanta, where she was shooting a Michael Showalter comedy, Chen said she deeply related to the film as a Chinese American mother who raised two daughters in San Francisco.

“That kind of confusion — and the complex, fraught relationship with the mother-in-law — that is something that all Chinese daughters-in-law understand,” said Chen. “The immigrant experience was something I was very familiar with.”

When Wang was making skate videos, he wasn’t just shooting tricks. He was drawn to making portraits of skaters and in-between moments. He was inspired by Spike Jonze’s skating videos and the atmospheric flavor of videos on the skating website the Berrics.

“It was just fun. I liked the feeling of shooting stuff, putting it in a timeline and putting music underneath and going: Are we capturing the feeling of what that day was like?”

The tools of filmmaking — a decent camera, the ability to post videos online — was making moviemaking more accessible, even if Wang didn’t start thinking about narrative films until film school at the University of Southern California. He’d later participate in several Sundance Institute labs.

By then, films like Ryan Coogler’s “Fruitvale Station,” Destin Daniel Cretton’s “Short Term 12” and Barry Jenkins’ “Medicine for Melancholy” were expanding Wang’s sense of cinematic possibilities.

For Izaac Wang, 16, making “Dìdi” was a way to channel his own adolescent hardships growing up while experiencing a coming of age of his own. Wang became friends with the actors who play Chris’ friends in the movie; they stayed together at Sundance.

“I learned a lot through this movie whether it be about acting or just being a better human being,” says Wang. “The overall feel of the crew, how everyone felt like a small family, was very heartwarming.”

Together, Chen and Wang make up one of the more indelible mother-son portraits in recent years. Wang felt himself being reshaped in more ways than one. “I used to have really good posture before this movie,” he says. “But every scene, Sean would be like, ‘Can you just slouch a little bit more?’ Ever since then, I’ve just never been able to sit straight.”

Chen says “Dìdi” ultimately felt “like destiny” for its young director. Sean Wang, having experienced such a breakthrough, seems cognizant that everything has changed for him a filmmaker now.

“I was talking about it with friends of mine recently, all the skate videos and stuff I was making as a kid, in my teenage years and even early college, there was no fear attached to any of it,” says Wang. “Now, for better and for worse, there’s always an element of fear. Because you want it to be good.”

“Yeah,” he adds, smiling, “but don’t look at my YouTube channel.”