In 1995, Pixar released a little film called “Toy Story” that brought characters to 3D life, via computer-generated imagery. The movie mesmerized audiences and saw boffo box-office receipts.

But its enormous success was the beginning of the end for the traditional, hand-drawn animation that had charmed audiences since 1937’s “Snow White and the Seven Dwarfs.” Studios turned to the new style, and even Disney abandoned the old, releasing its last 2D feature, “Winnie the Pooh,” in 2011.

Leave it to Netflix to shake things up with its first animated feature: “Klaus,” a Santa origin story made the old-fashioned way: in 2D.

“Klaus,” which hits select theaters Friday before streaming Nov. 15, follows a young postman named Jesper (voiced by Jason Schwartzman) who’s exiled to frigid Smeerensburg until he’s able to deliver 6,000 letters. After encountering a mysterious old toymaker, Klaus (J.K. Simmons), Jesper crafts a wily plan to deliver the mail.

It’s a tale, says director Sergio Pablos, who co-created “Despicable Me” and worked on Disney’s “Tarzan,” that begged for an old-school touch. “When you have a story that has a very organic quality to it and a nostalgic element, then it feels appropriate for traditional animation, because those are traits of that medium,” Pablos tells The Post.

He says producer Jinko Gotoh initially dismissed the idea, but when he showed her an animation test in 2015, she was blown away, both by the story and the visual style, a blend of old and new techniques.

“I wanted to take traditional animation to the next level,” Gotoh tells The Post. “I was very invested in making that happen.”

To the untrained eye, the characters of “Klaus” may look like CGI. But while the filmmakers used CGI to animate, say, moving vehicles, the characters are hand-drawn, just as Disney’s original Cinderella and Ariel were. The difference is something called volumetric lighting, a process that gives Jesper and Klaus the appearance of depth.

Texturing also allowed for a more seamless merger of characters and their backgrounds. That, and the lighting, created a look that’s significantly less flat than the 2D films of yesteryear.

The hardest part, say Pablos and Gotoh, was finding animators who could do it.

“I thought most of our crew was going to have to be veterans that we broke out of retirement homes and jails,” jokes Pablos.

While he enlisted old-school animators from 2D’s glory days, he was shocked to also find millennials who were still choosing to pursue traditional animation, just as Pablos did when he was in school in the ’80s.

“I did it because it was a passion move. It had nothing to do with career expectancy,” he says. “These guys are making the same decision based on what they love … It just made my heart warm.”

After all, those young adults were inspired by the traditional animation they grew up watching. Perhaps, Pablos says, “Klaus” can do the same for a new generation of animators.