Bump was an application, created by GoCardless in 2015, which helped keep project dependencies up to date.
Since 2017, Dependabot has fulfilled the same needs, whilst offering a wider range of features and tools to teams and individuals.
Dependabot is powered by dependabot-core, which is the spiritual successor to the bump-core project.
Bump Core was a library containing the logic to keep a project's Ruby, JavaScript and Python dependencies up to date. It was used by [Bump][bump].