A frequently asked question is how Perkeep compares to similar software and services.
Remember that Perkeep‘s goal is to keep your data for your entire life. Let’s call that 100 years. Or longer, if you want to pass your data down generations. That influences a number of aspects of Perkeep's design.
Perkeep is software that you can run on your own machine, or that you can run on the cloud yourself, but it is not a hosted service by a for-profit company. Many companies host your files, but we wouldn't count on any one of them to stay in business or not change business models in 100 years. Sites often die and lose user data.
Many services start free to get rapid growth but later close when they don‘t achieve enough growth, or don’t find a business model that works and their investors aren't happy. By paying for keeping your own data, you avoid the uncertainty of what other people (companies, investors) are going to do to your data.
We do provide the Cloud Launcher to run a copy on Google Compute Engine yourself. Perkeep runs happily on desktop machines, Raspberry Pis, home servers, Amazon EC2, Google Cloud Platform, or any other cloud provider. We suggest using at least two for redundancy. Your replicas can sync amongst themselves.
In addition to being software instead of a service, Perkeep is open source software. That means that even if computers are much different in 100 years, you‘ll still have hope of you or somebody else updating Perkeep to run on them. Or at least you’ll be able to read the code and figure out the on-disk representation, if Perkeep's verbose, data-archaeology-paranoid formats leave any doubt.
It also means many people can contribute, instead of one company that might go out of business or change priorities.
Perkeep‘s data model is based primarily on nameless objects. Perkeep can model traditional files with filenames and a POSIX filesystem, but it can just as happily represent a tweet or a “like” with no name. Perkeep is built as something you casually throw data into and don’t worry about organizing too much. It's all indexed so you can search for it later. Or you can give it a name (or multiple names!) if you prefer, but you can do that whenever you want later. You can even have objects or files with multiple parent containers.
Many other products & services assume a file-centric view of the world. Perkeep takes the view that files are becoming less important over time. People care about backing up and searching their content, not their files. (Note that iOS went about 10 years before having a file browser or any concept of files.)
Because Perkeep can handle objects so well, we can import your tweets or likes or check-ins or other social media content in a more natural representation, rather than inventing files and names for everything.
So, how does Perkeep compare to others?
Upspin is also open source, and has many similar goals. It differs in that its data model is very file-centric, with everything having a name. It has prioritized sharing between users via a global namespace and a global filesystem. See the section on Objects, not files above.
Upspin was announced on 2017-02-21, about 6.5 years after Perkeep (Perkeep was named Camlistore at the time).
There are probably interesting collaboration areas between Upspin and Perkeep. They share at least one common contributor familiar with both systems. One could imagine Perkeep users creating a share that is exported as an Upspin namespace, in the same way that Perkeep users can mount their data with FUSE.
(this answer was largely taken from an old Hacker News comment)
IPFS is an impressive and ambitious project. It also has some similarity to Upspin and Perkeep. Like Upspin, IPFS wants to have a global namespace and be a filesystem. See https://github.com/ipfs/ipfs#quick-summary. Like Perkeep, the content-addressable bits and representation of files is similar.
Perkeep uses an Objects, not files data model, which makes writing importers for third-party sites easier when that third-party content doesn't have an obvious file representation.
IPFS development began about 5 years after Perkeep. There is plenty of room for collaboration between the two projects. Perkeep should probably have an IPFS backend.
Perkeep will probably have some optional integration with Keybase.
git-annex is file-centric. See the section on Objects, not files above.
Google Drive is a service, not open source software. See the section on Software, not a service above.
That said, Google Drive is a really nice service with features like OCRing of images, object recognition of photos, and great search. Many of the Perkeep authors regularly use Google Drive, and we have the start of an importer. See the tracking bug.
Dropbox is a service, not open source software. See the section on Software, not a service above.
There is a tracking bug for a Dropbox importer.
See the prior art page for some others.