Front-end Web Development Deployment Syllabus

In GitHub Actions, define the hierarchy: workflow, job, step, and action.

A workflow contains one or more jobs; each job runs on a runner and contains a sequence of steps; a step is either a shell command or an 'action' (a reusable packaged unit of code).

In GitHub Actions, what does the `on` key specify? Give example triggers.

It specifies the events that trigger the workflow, e.g. `push`, `pull_request`, `schedule` (cron), `workflow_dispatch` (manual), or `release`.

What is a 'runner' in GitHub Actions?

A server that executes a job. GitHub provides hosted runners (Ubuntu, Windows, macOS), or you can register self-hosted runners on your own infrastructure.

In a GitHub Actions job, what is the difference between `uses` and `run`?

`uses` invokes a reusable action (e.g., `actions/checkout@v4`), while `run` executes shell commands directly on the runner.

How do jobs run by default in GitHub Actions, and how do you force one job to wait for another?

Jobs run in parallel by default. Use the `needs` keyword to declare a dependency so a job waits until the named job(s) complete successfully.

How are secrets referenced in a GitHub Actions workflow?

Via the secrets context, e.g. `${{ secrets.MY_TOKEN }}`. Secrets are stored encrypted in repository/organization/environment settings and masked in logs.

What is the GitHub Actions Marketplace?

A catalog of reusable, community- and vendor-published actions that can be referenced in workflows to perform common tasks without writing them from scratch.

What is Travis CI?

A hosted continuous integration service that automatically builds and tests code from GitHub (and Bitbucket) repositories, historically one of the first popular CI services for open source.

What configuration file does Travis CI use, and in what format?

`.travis.yml`, written in YAML, placed at the root of the repository.

In a `.travis.yml` file, what does the `language` key do?

It selects the build environment and default toolchain for a project (e.g., `language: node_js`, `python`, `ruby`), determining preinstalled tools and default build/test scripts.

Name the main Travis CI build lifecycle phases in order.

Optional `before_install`, then `install` (dependencies), optional `before_script`, `script` (the build/test), and `after_success`/`after_failure`, then optional `before_deploy`, `deploy`, and `after_deploy`.

What does the `script` phase control in Travis CI, and how is build success determined?

`script` defines the commands that build/test the project. The build passes if every command exits with status 0; a non-zero exit code from any script command fails the build.

What is the `matrix` (build matrix) feature in Travis CI?

A way to run the build across multiple combinations of languages, runtime versions, and environment variables in parallel, e.g. testing against several Node.js versions at once.

What is CircleCI?

A cloud-based (and self-hostable) CI/CD platform that automates building, testing, and deploying code, known for fast parallelized pipelines and Docker-first execution.

What configuration file does CircleCI use, and where is it located?

`.circleci/config.yml`, written in YAML, located in the `.circleci/` directory at the repository root.

In CircleCI, define: pipeline, workflow, job, and step.

A pipeline is the full set of work triggered by a commit; a workflow orchestrates and sequences jobs; a job runs in an executor and contains steps; a step is a command or built-in action.

What is an 'executor' in CircleCI? Name common types.

The environment in which a job runs. Types include `docker` (container images), `machine` (a full Linux VM), `macos`, and `windows`.

What are CircleCI 'orbs'?

Reusable, shareable packages of YAML configuration (commands, jobs, executors) that bundle common tasks, similar in spirit to GitHub Actions from the Marketplace.

In CircleCI, how do you control the order and dependencies of jobs?

Inside a `workflows` block, list jobs and use the `requires` key so a job only starts after its required jobs finish successfully; jobs without dependencies run in parallel.

What is the general purpose of a CI/CD pipeline in the context of front-end deployment?

To automatically build, test, and deploy code on each change, catching errors early and delivering updates reliably and repeatably without manual steps. CI = Continuous Integration; CD = Continuous Delivery/Deployment.

What is the difference between Continuous Delivery and Continuous Deployment?

Continuous Delivery automates the pipeline up to a production-ready build that is released manually; Continuous Deployment goes further by automatically releasing every passing change to production with no manual approval.

Classify these tools as primarily 'hosting/deploy platforms' vs 'CI/CD automation services': Netlify, Vercel, GitHub Pages, GitHub Actions, Travis CI, CircleCI.

Hosting/deploy platforms: Netlify, Vercel, GitHub Pages. CI/CD automation services: GitHub Actions, Travis CI, CircleCI. (Netlify and Vercel also include built-in CI/CD; GitHub Actions can also deploy.)

Compare the config file formats: Netlify, Vercel, GitHub Actions, Travis CI, and CircleCI.

Netlify uses netlify.toml (TOML); Vercel uses vercel.json (JSON); GitHub Actions uses YAML in .github/workflows/; Travis CI uses .travis.yml (YAML); CircleCI uses .circleci/config.yml (YAML).

Why is GitHub Actions often preferred over Travis CI or CircleCI for projects already hosted on GitHub?

It is natively integrated into GitHub (no third-party authorization), uses the same UI, has a generous free tier for public repos, and a large marketplace of actions, reducing setup friction.

What is an environment variable in the context of deployment, and why store secrets as them?

A key-value setting injected into the build/runtime environment (e.g., API_URL, API_KEY). Storing secrets as environment variables (rather than in code) keeps credentials out of version control and lets values differ per environment.

What does 'zero-config deployment' mean, as offered by Vercel and Netlify?

The platform auto-detects the framework and applies sensible default build commands and output directories, so a project can deploy without manually specifying build settings.

What is a 'rollback' in a deployment platform, and why is it valuable?

Reverting the live site to a previous known-good deployment. Because platforms like Netlify and Vercel keep immutable past deploys, rollback is near-instant and lets teams quickly recover from a bad release.

What is a build/deploy badge (status badge), and where is it commonly displayed?

An auto-updating image showing the latest CI build status (passing/failing), provided by services like Travis CI, CircleCI, and GitHub Actions, commonly embedded in a repository's README.

What is a webhook's role in connecting a Git repository to a CI/CD or deploy service?

When a configured event occurs (e.g., a push), the Git host sends an HTTP POST (webhook) to the service, which triggers the corresponding build/deploy pipeline automatically.

What does it mean that GitHub Pages, Netlify, and Vercel serve content over a CDN, and what is the benefit?

A Content Delivery Network caches static files on geographically distributed edge servers, so content is delivered from a location near each user, reducing latency and improving load times and availability.