Frequently Asked Questions

Does Slate Collaborate use Operational Transforms (OT) or Conflict-free replicated data type (CRDT) for synchronizing documents?

Slate Collaborate uses Operational Transforms (OT), a collaborative technology popularized by Google Docs and is used in popular products like Microsoft Word 365 and Dropbox Paper.

OT is used in production and has a proven track record.

Why does Slate Collaborate use OT?

Conflict-Free Replicated Data Type (CRDT) is a newer approach than OT to collaborative editing. It has Promise but is not widely adopted yet for rich text editing. Here's why we don't use CRDT:

• OT preserves intent, CRDT does not: Due to the way CRDTs encode changes, intent is not preserved across certain operations like split blocks. This means, some combinations of operations do not end up in the expected end state. For some, this is an acceptable trade-off but we selected OT due to its correctness.
• CRDT lacks a proven track record: OT is used in proven software like Google Docs, Microsoft Word 365 and Dropbox Paper. CRDT has promise and is interesting but its ability to perform in wide-scale production is not proven.
• OT adoption is high in editors while CRDT is not: OT is favored over CRDT in rich text editors such as CodeMirror 6, Xi Editor, CKEditor, and TinyMCE.

CRDT's have potential and its ability to converge to the same document without central coordination is attractive. One day, CRDT's may be the best option, but until that time, OT remain the preferred option.

What happens if Slate Collaborate is no longer supported?

There is a Business Continuity Protection guarantee. If for any reason Slate Collaborate is no longer supported, the license allows you to continue to use Slate Collaborate in your project without having to pay for it. You will be granted access to the source code if you do not already have access to it so you will be able to support it yourself or with others slate-collaborate developers.

For clarity, this does not mean that Slate Collaborate becomes open source. It means people that have paid for a license can continue using it without charge.

Can I host Slate Collaborate on my own servers?

Yes.

Can I host Slate Collaborate in the cloud?

Yes.

Is Slate Collaborate GDPR and HIPAA Compliant

Slate Collaborate includes features that make compliance possible such as:

• End-to-end encryption with SSL over WebSockets
• No long-term state is stored in the servers
• You can authenticate users through a callback hook in JavaScript/TypeScript. You can use it to authenticate against a database, LDAP server, using JSON tokens with client data from Cookies, LocalStorage or anything you choose.
• You can authorize access through a callback hook to prevent unauthorized access to sensitive editing data. For example, a specific user may have access to specific documents.

Do I get access to the source code

The Enterprise package includes the source code

If for any reason we can no longer support Slate Collaborate, you get access to the source code and the right to use the software in your project without charge.

How and where is document content saved?

The document content is saved into the data store of your app (probably a database) like any other content on your website or web app.

During an editing session, a copy of the document is stored in a Redis data store; however, at the end of the editing session, this data is deleted.

There are three ways to save data to your data store:

• On save: When a user clicks the save button, the document's value is saved into the app's database.
• At the end of an editing Session: If you want content automatically saved without having to click a save button, you can have content automatically saved to your database when an editing session ends. This is done through a callback function (in JavaScript or TypeScript) that you can define on the collaboration server.
• Real-time: As the user types, you can have changes (usually throttled) saved directly to the database. There is a callback function that gets called on every edit that you can edit to save edits to the database.

Who are you?

MeZine Inc. is a successful Internet Company started in 1999 to create tools to help end users and developers develop websites.

Sunny Hirai is the CEO of MeZine Inc. and a core contributor to Slate and has contributed the most commits and lines of code to the project that any other developer with the exception of Ian Storm Taylor, the creator of Slate. Sunny added Android support for the 0.47 version of Slate and created a successful KickStarter that raised about USD $25,000 which was used to fund the migration of Android support to the 0.5x version of Slate.

Wayne Leroux worked on the migration of Android support to the 0.5x version of Slate. wwwww Leroux built a platform these uses operational transforms to keep application in sync. Slate-Collaborate is an extraction of the rich-text editing portion of that framework.

What is Redis used for?

Slate Collaborate has a dependency on Redis. What is Redis used for?

Redis is used for two things:

• Store the current state including the operations for each document editing session.
• It is used as a publish/subscribe platform where multiple Slate Collaborate servers can stay synchronized by subscribing to a document editing session on Redis, and then listening for incoming operations to keep the document in sync.