A Single Source of Truth


Development based on a Single Source of Truth is like creating Cross Platform Interfaces for your Technology.

And just like a Java or CSharp interface, a Single Source of Truth allows you to make decisions once, and then act on those decisions consistently across multiple platforms and environments.

In a traditional development model, the same notions/ideas/concepts are defined again and again, will little to no concern for duplication.

Development based on a Single Source of Truth

To effectively use SSoT.me to develop software, it is important to have a clear understand of what a single source of truth is.

A good single source of truth is a Description of Technology which is a:

  1. Single
  2. Authoritative
  3. Machine Readable
  4. Platform Agnostic
  5. Queryable
  6. Description of What is needed


The most important aspect of a Single source of truth is that there is only one of them.  The most common mistake made in a “Traditional Development Model” is that the same notions are described again, and again, and again – and in each place we call that “Source Code”.


Many projects actually have development assets which would make good Single Sources of Truth, but they lack Authority.  In other words – after finding a good Single description of what is needed, the next KEY is designating that description authoritatively as “the” description.

Machine Readable

Another key aspect of developing an SSoT is that it must be machine readable.  Creating a single, one page picture of the technology is a fanstastic start.  But if that picture is embedded in a PNG that’s not as helpful as if it is in a simple JSon or Xml Description of a flow chart..

Platform Agnostic

SSoT’s which are easily read by Mobile, Desktop, Windows, Web, iOS, Android, Linux, etc are better than Single Sources of Truth which are targeted at a particular environment, language or technology.  Good examples of platform agnostic SSoT’s are:

  • Json
  • Xml
  • Csv
  • Xlsx
  • DBs (Sql, Postgress, MySql, NoSql, etc)
  • Google Docs/Sheets
  • etc


Description of What is needed

A key aspect of a good Single Source of Truth is that it contain as many of “the decisions” that have been made as possible.  In other words, the SSoT is the perfect place for all of the tribal knowledge.  In other words, once you’ve created the SSoT, there should be no tribal knowledge.

Because anything that would ordinarily be treated as “tribal knowledge” should be written down!