What is Ant?
The Ant migration tool is a free tool provided by Salesforce. It is a Java/Ant based command line utility for moving metadata between a local folder and an org. It's also known as the Force.com migration tool.
How does Ant work?
Ant is a command line tool. This means all interactions with it are managed via the Command Line Interface (CLI) - there is no user interface.
Ant allows users to deploy sets of metadata changes from one environment to another by building code packages by hand. Packages are built by the developer and organised into a single folder which is then deployed using the tool.
Alongside the actual metadata to deploy, Ant also uses the concept of a package file which acts as a sort of index for what is included in the deployment. Once the deployment is complete, the target org will be in sync with the changes included in the deployment package.
You can see a live example of building and deploying some changes with Ant in this video by Salesforce:
Benefits of Ant
For the experienced developer, Ant has a number of benefits over change sets:
It allows finer-grained access to the deployment process as it gives users total control over the metadata that is migrated.
It gives better visibility into the changes being deployed, as users can easily inspect the raw XML on their machine.
Ant can be integrated with source control systems, such as git, to allow developers to adopt a modern development process.
It’s useful for automating or controlling the deployment process more accurately. Anyone that prefers deploying in a scripting environment will find the Ant Migration Tool a familiar process.
A typical development process requires iterative building, testing, and staging before releasing to a production environment. Scripted retrieval and deployment of components can make this process much more efficient.
By integrating Ant with other automation tools, users can schedule deployments to run when they want them, or pull down changes to their development environment every day.
Challenges of Ant
Despite these benefits, Ant has a number of drawbacks which limit its adoption across teams:
Since it lacks a GUI, the Ant tool has a steeper learning curve than change sets. This lack of interface is a barrier to many non-developers and means many admins and teams are unable to use it at all.
Running deployments with Ant requires manual editing of metadata which is error-prone and time consuming.
Dependencies for the deployment package must be individually identified and incorporated, requiring a deep knowledge of Salesforce.
Comparison of files downloaded from different environments is a manual process, usually involving a specific diff tool to bridge the gap.
Cases of deployment failures with obscure failure messages (which turn out to be down to missing a character when copying between text files) are all too common.
As the tool is tied to a specific development environment on a computer, it's not well-suited for remote working or mobile teams, and its complexity makes it inaccessible to the majority of Salesforce users.
Is there a better way than Ant?
Yes! Gearset was specifically designed to replace command line tools like Ant and provide developers with a more powerful, yet easy-to-use tool to manage their releases. Ant has also been superseded by the CLI released as part of Salesforce DX. You can find out more about how Gearset works with DX here.