(NewsDiffs.org)

Back in October, the New York Times made substantial changes to a report about Occupy Wall Street protesters marching over the Brooklyn Bridge. Version one opened with: "After allowing them onto the bridge, the police cut off and arrested dozens of demonstrators." Version two, edited just 20 minutes later, opened: "In a tense showdown above the East River, the police arrested more than 700 demonstrators from the Occupy Wall Street protests who took to the roadway as they tried to cross the Brooklyn Bridge on Saturday afternoon."

The changes to the first paragraph drew criticism, as the question of whether the police had allowed the marchers onto the bridge was central to hundreds of disorderly conduct charges. It's worth noting that the changes were due to the fact that the story was first posted based on the reporting of one staffer, and then updated with the accounts of two more reporters, and that the final version included both sides of the story. However, a graphic that illustrated the change as an example of bias went viral.

The kerfuffle inspired former Times reporter Jennifer 8. Lee and sibling programmer duo Eric and Greg Price (the latter is formerly of Quora, now at Tddium) to build a site at a news hackathon at MIT this weekend that tracks changes made to Times stories using Github. The app is called NewsDiffs. "Diffing is a popular concept within computer programming, which outputs the differences between two files. It is typically used to show the changes between one version of a file and a former version of the same file," the site says.

So far the app has turned up mostly minor but interesting differences. The strikethrough indicates words that were removed from the final version:

"as the winner of Egypt’s first dramatic competitive presidential election"

"Singapore’s single-party rule dominance"

The fact that Syriza did not place first may make European leaders more likely to grant some concessions to Greece, but they also have to consider the larger economies of Spain and Italy, which are also under intense pressure.

Rodney King's obituary had a slew of major changes, as the original version was incomplete.

NewsDiffs has started with the Times and CNN but may expand to cover more publications in the future.

UPDATE, 4:40 p.m.: Ms. 8 Lee writes in to point us to this column by public editor Arthur Brisbane, which addresses the importance of tracking changes on nytimes.com. Executive editor Jill Abramson told Mr. Brisbane that it's "unrealistic to preserve an 'immutable, permanent record of everything we have done,' as if the Times were a professionally-maintained Wikipedia. "But actually, with version control software, we can get a pretty good approximation," Ms. 8 Lee said in an email. "Developers have solved this problem. We just have to use it."