Version control

Version control is the practice of to record all changes made to a piece of software code. Let’s say it’s the equivalent of saving your progress in a video game. This tool or feature is very useful in any development project, and essential for a DevOps even. 

What is a version control system used for?

It allows us to go back in time and restore a previous version of the code, in case we have made a mistake and need to check other versions to compare them and pinpoint the error. In this way, it saves a lot of time when correcting errors, it causes less disruption to other team members and, as a result, streamlines work processes.

As a general rule, version control software tends to save versions of the code on a regular and automated basis, which makes them very effective and user-friendly. Furthermore, version control also keeps a record of which specific developer made which changes and allows several developers to work on the same code at the same time.

Conversely, not having version control software can cause a great deal of trouble. For example, if data is accidentally lost at any stage of the project, we will not be able to recover the most recent changes made, but only those from the last version we saved manually. It would be just as complicated and time-consuming to debug without a comprehensive record of code changes that includes crucial details such as what, when and why.

Benefits of version control

Version control offers users the following benefits:

• Full change history: We can track all the changes made to files over time, including who made them, when and why. This makes it easier to identify errors by comparing the current version with previous, correct versions.
• Branching and mergers: It allows you to work on independent workflows and merge changes in a controlled manner, which facilitates collaboration within teams whilst also giving each member of the development team the autonomy to make changes freely.
• Traceability and notes: In a version control system, every change made to the software is recorded. Furthermore, the software is linked to other project management tools, making it easier to analyse the root cause of any code errors.

Types of version control systems

There are three main types of version control systems:

• Distributed: Enables staff to work on cloned repositories without an connection to the main server. Ideal for teams seeking flexibility and productivity, although it can result in long waiting times when downloading extensive logs or large binary files. Some of the most popular distributed version control systems are Git, Mercurial and Bazaar.
• Centralised: Use a registration/insertion flow to connect to the main server, automatically saving changes to the repository. Although it is potentially more secure and easier to set up, it requires a constant network connection and can cause problems when scaling up the project or merging changes from many developers. Subversion (SVN), CVS (Concurrent Versions System) and SCSS (Source Code Control System).
• Location: The most basic form, which is typically used by freelance developers, stores all the project data on a single computer and records changes as local revisions. It is less flexible and secure than centralised or distributed systems, but suitable for small projects before the project grows in size and team. The most commonly used local version control programmes are RCS (Revision Control System) and SCCS (Source Code Control System). However, developers often prefer distributed or centralised systems even for individual projects due to their greater flexibility and functionality.