Critics are giving mixed reviews to Snowden, the Oliver Stone film that opens in theaters on Friday. But as I wrote this week, the movie is essential viewing for anyone who cares about the national security debate and NSA’s co-opting of familiar technology like Google and Facebook to spy on us.

One reason the movie is worth watching is the realistic depiction of technology and hacker culture. Even as Snowden engages in Stone-style propaganda to support its hero, it avoids the stupid clichés that often appear when Hollywood takes on tech topics. I spoke with screenwriter Kieran Fitzgerald and technical supervisor Ralph Echemendia, who explained that Edward Snowden himself read drafts of the film and corrected details he felt were inaccurate.

Here are five aspects of the film that make Snowden a convincing tale about tech.

1. The Stickers on Snowden’s Laptop

The red and green stickers are hard to make out the first few times that Snowden (well, Joseph Gordon-Levitt) pulls out his laptop. But in the final scenes it’s clear what they are: A sticker from the Electronic Frontier Foundation, the influential San Francisco-based civil rights group, and one for TOR, the popular protocol that lets people access the Internet without revealing their location.

Both the EFF and TOR are important fixtures in the tech world, and the stickers are also affixed to Snowden’s laptop in real life.

2. A Clip from Sen. Ron Wyden

Sen. Ron Wyden (D-Or) is the most prominent voice in Congress for digital privacy, and his knowledge of technology makes him well-respected by journalists and by Silicon Valley. It’s no surprise then that, when the movie shows real-life news clips about the surveillance scandal revealed by Snowden, one of the people we see is Wyden.

Get Data Sheet, Fortune’s technology newsletter.

3. The Computer Screens Are Realistic

Images of people—even spies—tapping away on computers make for boring movie footage, so Hollywood usually resorts to showing silly fake green display screen to make it more interesting. Not Snowden. The film takes pains to make the computers and coding appear accurate, including a series of Bash commands Snowden uses in a test at CIA training school.

According to Fitzgerald and Echemendia, Edward Snowden helped them to replicate what a real NSA log-in screen looks like. They also set up the computers on set in such a way that the actors had to actually navigate programs, rather than just tapping any button to trigger an impressive-looking response.

4. Hacker Lingo

Fitzgerald said a challenge in a movie like Snowden is to appeal to the American public, which includes many people who don’t know or care about geek-speak, while also remaining credible with hacker types. The movie gets this balance right by keeping almost all of the dialogue in plain English, but throwing in just enough hacker talk to remind us the characters are hard-core computer guys.

That’s why there are phrases in the film like “SQL injections and malware” and “zero day exploit codes” and “snarfing the hardware ID”—the latter phrase, said Fitzgerald, came right from Edward Snowden himself.

5. The Rubik’s Cube

A recurring image in the movie are Rubik’s Cube puzzles. Snowden fiddles with the toys in several scenes and, at a critical juncture of the film, hides a tiny SD card in a Rubik’s Cube square in order to sneak out secrets from an NSA lab in Hawaii. It’s a cool scene and also works well since Rubik’s Cube is a good metaphor for the cryptography that is an important part of the film, and is even the subject of academic papers by math scholars.

As it turns out, however, the Rubik’s Cube was a dramatization by the film makers—but one Edward Snowden himself suggested, according to Fitzgerald. (Snowden has not said how he got the data out of the NSA lab in real life, but said it was in a way similar to the Rubik’s Cube trick.)