I have spent the two weeks modernizing a long dormant project at Contiamo. Not only did this require updating various dependencies and subsequently parts of the code base, but it also meant updating an old Jenkinfile into a Github Action workflow. 😬😬😬
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I think it is an uncontroversial statement to say testing is important in software development. Writing tests may not always be fun, but nothing is a sweet as that moment when a unit test catches a bug before you deploy.
In OpenFaaS we have tons of tests in each project, even the certifier itself runs a short suite of end-to-end tests. But, not all of our function templates have first class testing support.