Heroku

Heroku remains the simplest way to deploy full-stack apps. The 2025 “Fir” generation runs on AWS Graviton (ARM) and integrates native AI capabilities.

When to Use

• Simplicity: “Git Push Heroku Master”. No K8s, no Dockerfiles (optional).
• Stateful Apps: Heroku Postgres is arguably the best managed Postgres service in existence for developer experience (DX).
• MVP: Fastest time to market for Rails/Django/Node apps.

Quick Start

heroku create
git push heroku main

# Add Postgres
heroku addons:create heroku-postgresql:standard-0

Core Concepts

Dynos

Lightweight Linux containers. Pro/Enterprise dynos sleep only when told. 2025 includes Performance-L (Large) and Eco types.

Buildpacks

Scripts that detect your language (e.g. package.json -> Node) and build the app.

Releases

Atomic deployments. You can instant-rollback to v42 if v43 breaks.

Best Practices (2025)

Do:

• Use Environment Variables: 12-Factor App methodology is native to Heroku.
• Use Review Apps: Spin up a temp Heroku app for every Pull Request automatically.
• Use Docker (Container Registry): If Buildpacks fail you, push a Docker image.

Don’t:

• Don’t use local filesystem: Dynos are ephemeral. Files written to disk vanish on restart. Use S3.

References

• Heroku Documentation