Question 1

Why does everyone use github instead of just emailing each other code files?

Accepted Answer

The email-and-file-attachment model for sharing code breaks down in specific ways that become obvious quickly once more than one person is working on a codebase, and GitHub's value is best understood by working through exactly where it breaks.

When code lives in files attached to emails, there is no authoritative version. If two people modify different copies of the same file and email their changes back, someone has to manually reconcile them, figuring out which lines conflict and what the combined correct version should be. That reconciliation process is error-prone, doesn't scale beyond a few collaborators, and produces no record of why any specific change was made or by whom. If something breaks after a change, finding out what changed and who changed it requires searching through emails and comparing file timestamps, which works poorly even for a two-person team.

Git, the underlying version control system that GitHub is built on, solves the reconciliation problem through a structured merge process. Every change is tracked, attributed to a specific person, and accompanied by a message describing what was changed and why. When two people modify the same file in incompatible ways, Git surfaces the conflict explicitly and requires a human to resolve it deliberately, rather than silently overwriting one version with another. The entire history of every change to every file is preserved and searchable, so questions like "who changed this line and when" and "what was in this file six months ago" have reliable answers.

GitHub adds collaboration infrastructure on top of Git. The pull request is the central unit: when someone wants to add their changes to the main codebase, they open a pull request that shows exactly what they changed, line by line. Other team members can review the changes, leave comments on specific lines, request modifications, and approve or reject the change before it's incorporated. That review process — asynchronous, documented, and tied to the specific code — is fundamentally different from emailing someone a file and asking if it looks okay.

GitHub also provides issue tracking for bugs, features, and tasks that lives alongside the code, wikis for documentation, and a release management system for tracking what code is deployed where. All of this is searchable and tied together, so a team can trace a bug report to the specific change that introduced it and to the discussion that happened during its review.

The network effect is also worth naming. GitHub is where the vast majority of open-source code is hosted, which means that when you use open-source libraries — and nearly every software project does — you're already interacting with GitHub. Having your own code on GitHub means your team is already familiar with the workflow, integrations with open-source tooling are straightforward, and external contributors can work with your codebase using the same tools they use everywhere else.

For any team of more than one developer working on code that runs in production, the cost of not using version control compounds rapidly with team size and codebase complexity. GitHub is the most widely used platform for this workflow, which means tooling support, documentation, and hiring familiarity are all strongest there.

Question 2

What are github actions and do we need them or is it just more tooling?

Accepted Answer

GitHub Actions is GitHub's built-in automation system, and whether you need it depends on what you're currently doing to test and deploy your code — or not doing, if you don't have that infrastructure yet.

The basic concept is that GitHub Actions lets you define workflows in YAML files that live in your repository, and those workflows run automatically in response to events. The most common event is a push or pull request — when code is pushed to a branch or a pull request is opened, a workflow runs that does whatever you've defined: running your test suite, building a container image, checking code style, deploying to a staging environment, or any other repeatable process your team needs to run on code changes. The workflow runs on GitHub's infrastructure without any server setup required on your end.

An Action is a reusable unit of work that you compose into a workflow. GitHub's marketplace contains thousands of pre-built actions contributed by both GitHub and the community, covering common needs like setting up a specific programming language runtime, authenticating to a cloud provider, deploying to a hosting service, sending a Slack notification, or publishing a package to a registry. Building a workflow that runs your tests on every pull request and then deploys to production on merge to main can be done by composing existing actions without writing much automation code from scratch, once you understand the YAML structure.

The case for needing GitHub Actions is straightforward: if your team has no automated way to run tests on code changes, people will push changes that break things without catching it before it's in production. If deploying your application involves manual steps — connecting to a server, pulling code, restarting a process — GitHub Actions can automate those steps so deployment is triggered by a merge rather than a manual operation. Those two capabilities — automated testing on pull requests, and automated deployment on merge — are the baseline that most engineering teams want, and GitHub Actions is the most natural place to implement them if your code is already on GitHub.

The case for not needing GitHub Actions specifically is if you already have a CI/CD system you're happy with — Jenkins, CircleCI, Travis CI, GitLab CI, or something else — and your workflows are already running well there. GitHub Actions doesn't need to be adopted if an existing system is working. Actions also imposes some GitHub-specific YAML structure that takes time to learn, and for complex pipeline requirements, other CI/CD systems may have features or integrations that better fit specific needs.

For teams starting fresh, GitHub Actions has the advantage of requiring no additional account setup, no separate billing relationship, and no integration plumbing between your CI/CD tool and GitHub — it's already there. The free tier on GitHub includes a meaningful monthly allocation of Actions minutes for private repositories, and public repositories receive unlimited free minutes, which means the cost of getting started is low.

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Why does everyone use github instead of just emailing each other code files?

What are github actions and do we need them or is it just more tooling?