If you were to customize a calendar by marking off the events most integral to Boston film culture, there’s one week you’d highlight a shade deeper than the rest: The Independent Film Festival Boston, which kicks off its 13th iteration on April 22. Statistics indicate that this event is our city’s biggest cinema celebration, stretching across eight days and four venues with parties, conferences, a two-day “film summit,” and special guests throughout. But, as it should be, it’s the chosen films that really mark this film festival as our city’s best.

Two years ago, director James Ponsoldt provided the opening night feature with his teen-movie melodrama The Spectacular Now. His follow-up—The End of the Tour [April 22, Somerville, 7:30pm], featuring Jason Segal as David Foster Wallace—has been afforded the same honor this year. The film adapts a book-length interview with the late author, and co-stars Jesse Eisenberg as Segal’s sparring partner. Tour won raves when it premiered at Sundance (but that did little to extinguish the ire of members of Wallace’s estate who have vocally objected to the feature’s release.) Both Segal and Ponsoldt are scheduled to attend the screening, so any objections that arise in the Boston crowd can be answered face to face.

Special guests at the screenings and after-parties are par for the course at IFFB. Sunday’s special screening will be the world premiere of The Primary Instinct [April 26, Somerville, 7:30pm], which documents the live performances of actor-slash-raconteur Stephen Tobolowsky (Groundhog Day), and it will be followed by a conversation with director David Chen and Tobolowsky himself.

And he’s not the only veteran stage-performer on-hand. IFFB favorite Bobcat Goldthwait will serve as the center of Saturday night’s festivities, hosting a screening of his new documentary Call Me Lucky [Apr. 25, Somerville, 7pm]. And like Chen, he’s bringing his subject—storied Boston funnyman Barry Crimmins—along with him. (Goldthwait’s Q&As have become legend at the IFFB, so stick around well after the movie ends. Trust me.)

Goldthwait’s move away from narrative films mirrors a shift within the festival itself. As strong as the fiction lineup is, the documentaries have dominated pre-fest chatter, with the works of masters young and old scheduled throughout. One of the last films by the late, great Albert Maysles, Iris [April 25, Somerville, 7:15pm], will make its regional premiere on Saturday night. (In Transit, another doc that Maysles contributed to, will play as well—Somerville, Sunday, 12:30pm.) And Harvard grad Joshua Oppenheimer, whose Act of Killing undoubtedly ranks among the most significant documentaries of the past few decades, will be showing his companion piece—The Look of Silence [April 26, Brattle, 6pm].

Call us biased, but our favorite film among the bunch we’ve screened thus far would be Results [April 23, Brattle, 7pm], the latest by Andrew Bujalski, a Boston-born IFFB veteran. A hip Austin gym serves as the setting for a love triangle among depressives—Kevin Corrigan as a rich divorcee, Guy Pearce as an anxious new-age trainer, and Cobie Smulders as his perpetually enraged employee. Bujalski’s last film, the avant-garde whatsit Computer Chess, detonated his prior reputation as a darling creator of indie dramedies. So now he’s moving in the opposite direction—Results consciously indulges an unending streak of romcom cliches, assigning itself to the most tired genre of all. But he outfits the picture with wacko formal flourishes throughout: Check out the way he sets a late montage to a series of intersecting songs, as if to purposefully throw off the rhythm. What emerges is a film as strangely endearing as its characters—what emerges is true eccentricity.

But to speak only of our favorite artists would marginalize the festival’s finest feature. The programming is dense to the extent that most years one leaves championing something one hadn’t heard of even a week prior. The films mentioned here can sell you a ticket, but the real fun is in sticking around afterwards. You can always count on discovering something brand new.

INDEPENDENT FILM FESTIVAL BOSTON 2015. APRIL 22-29 AT THE SOMERVILLE THEATRE, BRATTLE THEATRE, COOLIDGE CORNER THEATRE, AND UMASS BOSTON. VISIT IFFBOSTON.COM FOR TICKETS, BADGES, AND SCHEDULE.