Softwr

Cloud · head to head

Fly.io vs Terragrunt

Fly.io logo

Fly.io

Cloud

Deploy web applications globally

From
$29/month
Rated
-
Full reviewWebsite
Terragrunt logo

Terragrunt

Cloud

The Open Source IaC Orchestrator Platform Teams Trust

From
Free
Rated
-
Full reviewWebsite

The short version

  • Only Terragrunt has a free tier, so it costs nothing to try first.
  • Each has a real cost: Fly.io egress is priced by destination region, from $0.02 per GB in North America and Europe to $0.12 per GB for Africa and India, so the same traffic costs six times more depending on where users are; Terragrunt additional complexity layer on top of Terraform
  • They diverge on capability: Fly.io covers Global deployment, Terragrunt covers Infrastructure orchestration.

Where they differ

Only the attributes on which Fly.io and Terragrunt actually diverge.

Attributes where Fly.io and Terragrunt differ
AttributeFly.ioTerragrunt
Starting price$29/monthFree
Pricing modelusage-basedUnknown
Free tierNoYes
PlatformsWeb, Api, DockerAWS, Azure, GCP
Founded2020Unknown

Identical on both: user rating (Not yet rated), category (Cloud).

What each one covers

Drawn from each product's published feature list. An absence here means we hold no record of it - not that the product lacks it.

Only in Fly.io

  • Global deployment
  • Docker support
  • Postgres databases
  • Redis support
  • Auto-scaling
  • Health checks
  • Backups
  • Monitoring

Only in Terragrunt

  • Infrastructure orchestration
  • Run Queue
  • DRY configuration
  • Automated hooks
  • Infrastructure catalog
  • Least-privilege access

What people use each for

The jobs each tool is most often brought in to do.

Fly.io

  • Deploying containerised applications close to users across regionsnot Terragrunt
  • Running full stack apps and databases on managed machinesnot Terragrunt

Terragrunt

  • Organizing Terraform code across multiple environmentsnot Fly.io
  • Automating infrastructure deployment workflowsnot Fly.io
  • Implementing infrastructure as code templates for developer self-servicenot Fly.io

Where each one falls short

Documented limitations, not opinions. Every one is a constraint you would hit in normal use.

Fly.io

  • Egress is priced by destination region, from $0.02 per GB in North America and Europe to $0.12 per GB for Africa and India, so the same traffic costs six times more depending on where users are
  • Stopped machines still bill at $0.15 per GB of root filesystem a month, so a paused service is not a free one
  • Volumes are billed on provisioned capacity rather than usage, at $0.15 per GB a month
  • Reservation discounts of 40% require paying a year up front, from $36 to $1,440
  • Fly Kubernetes is a separate $75 a month per cluster
  • Dedicated IPv4 addresses are $2 a month each

Terragrunt

  • Additional complexity layer on top of Terraform
  • Requires understanding of Terraform concepts
  • Paid tier pricing not clearly published

Pricing, plan by plan

Fly.io

$29/month
  • Pay-as-You-Go$null/mo
    • Micro VMs and persistent storage charged by usage
    • FlyCTL CLI
    • Unlimited users and organizations
  • Serious Support$29/month
    • Access to dedicated engineering team
    • All Pay-as-You-Go features
  • Machine Reservation Blocks$null/mo
    • 40% discount on machine usage
    • Requires upfront payment for savings
  • Compliance Package$99/month
    • HIPAA compliance
    • BAAs
    • SOC2 documentation

Terragrunt

Free
  • Open SourceFree
    • Terragrunt CLI - completely free
    • Community support
  • Terragrunt Scale FreeFree
    • Free CI/CD pipeline
    • Unlimited runs and resources
    • For up to 25 infrastructure units
  • Terragrunt Scale Paid$undefined/custom
    • Volume pricing for more than 25 infrastructure units
    • Enterprise support

Which should you pick?

Choose Fly.io if

  • You need global deployment.
  • You work on Web, Api, Docker.
  • You also want docker support.
Fly.io review

Choose Terragrunt if

  • You need infrastructure orchestration.
  • You want to start without paying.
  • You work on AWS, Azure, GCP.
  • You also want run queue.
Terragrunt review

Questions people ask

Is Fly.io or Terragrunt better?
Neither clearly leads. Fly.io starts at $29/month and Terragrunt at Free, and user ratings are close enough to be indistinguishable. Choose on capability and platform support.
Which is cheaper, Fly.io or Terragrunt?
Terragrunt has a free tier; the other does not. Paid plans start at $29/month for Fly.io and Free for Terragrunt.
Does Fly.io or Terragrunt run on more platforms?
Fly.io runs on Web, Api, Docker. Terragrunt runs on AWS, Azure, GCP.
Can I use Terragrunt for free?
Yes. Terragrunt has a free tier, so you can try it without paying. Fly.io starts at $29/month.
What is Fly.io best used for?
Fly.io is most often used for deploying containerised applications close to users across regions, running full stack apps and databases on managed machines. Of those, deploying containerised applications close to users across regions and running full stack apps and databases on managed machines are not what Terragrunt is typically brought in for.
What can Fly.io do that Terragrunt cannot?
Fly.io covers Global deployment, Docker support, Postgres databases, Redis support. Terragrunt covers Infrastructure orchestration, Run Queue, DRY configuration, Automated hooks.

Answered from the vendors’ own pages

Fly.io: Is there a free tier for Fly.io?

Fly.io does not advertise a free tier. The base plan is pay-as-you-go with usage-based pricing for Micro VMs and persistent storage. All users get FlyCTL CLI, unlimited organizations, private networking, SSO, ACLs, and scoped tokens.

Source
Terragrunt: Is Terragrunt free?

Yes, the Terragrunt CLI is completely free and open source. Terragrunt Scale offers a free tier for up to 25 infrastructure units.

Source
Fly.io: How much does Fly.io Serious Support cost?

Serious Support costs 29 USD per month and provides access to a dedicated engineering team while maintaining all pay-as-you-go features for Micro VMs and storage.

Source
Terragrunt: What is the difference between Terragrunt and Terraform?

Terragrunt is an orchestration layer on top of Terraform that handles state management, DRY principles, and deployment automation without replacing Terraform itself.

Source
Fly.io: What does Fly.io Compliance Package include?

The Compliance Package is 99 USD per month and includes HIPAA compliance, BAAs, and SOC2 documentation for organizations requiring compliance certifications.

Source
Fly.io: Does Fly.io offer discounts for upfront commitment?

Yes, Fly.io offers Machine Reservation Blocks with 40% discount on machine usage. This requires upfront payment but applies savings on infrastructure costs.

Source
Share

Related pages

More on Fly.io

More on Terragrunt

Keep looking

Other head to heads