Coolify vs Fly.io: Which One Should You Choose? (2026)

If you're a self-hosting enthusiast who wants full control over costs and infrastructure, Coolify is your jam. But if you need global edge distribution and don't mind a bit of platform lock-in for performance, Fly.io might be the way to go. Both have free tiers, so let's see which fits your project.

Hey there, fellow devs! When you're looking at Coolify vs Fly.io 2026, it's like choosing between building your own workshop or renting space in a global co-working hub. Coolify lets you run everything on your own servers, while Fly.io spins up containers close to users worldwide. From what I've seen, the right pick depends on whether you're optimizing for cost or performance. Let's dive in and see which one fits your project.

Quick Overview

What is Coolify?

Coolify is an open-source, self-hostable Platform as a Service (PaaS) that's kind of like having your own private Heroku. It runs on your servers via Docker, so you can deploy static sites, full-stack apps, databases, and over 280 one-click services. Think of it as the DIY approach—you own the hardware, but Coolify handles the orchestration. It's perfect if you're tired of vendor lock-in and want to keep costs predictable.

What is Fly.io?

Fly.io is a container-based PaaS that uses hardware-virtualized micro-VMs called Fly Machines to run apps globally. Imagine it as a distributed cloud that puts your code close to users, similar to how CDNs work for static content. It's built for modern apps with features like edge functions and GPU support, making it a go-to for real-time or AI projects. In my experience, it's a solid choice if you need low latency and don't want to manage servers.

Key Differences at a Glance

Here’s a quick side-by-side to help you scan:

Coolify: Strengths & Weaknesses

Strengths

• Cost control: Run it on cheap VPS or existing servers—pay only for infrastructure.
• Full feature access: When self-hosted, you get all capabilities like custom domains, cron jobs, and persistent storage.
• Avoid vendor lock-in: Since it's open-source and Docker-based, you can move easily.

Weaknesses

• No edge runtime: If you need global edge functions, you'll have to look elsewhere.
• Infrastructure management: You're on the hook for OS updates, security, and scaling.
• Community support: Free tier relies on community, which can be hit or miss.

Fly.io: Strengths & Weaknesses

Strengths

• Global performance: Apps run close to users with low latency, thanks to edge distribution.
• Rich feature set: Includes edge functions, GPU support, analytics, and rollbacks out of the box.
• Managed infrastructure: Fly.io handles the heavy lifting, so you focus on code.

Weaknesses

• Learning curve: Requires Docker and CLI knowledge, which can be steep for beginners.
• Cold starts: Machines that scale to zero might have delays on first request.
• Platform-specific: Configs are tied to fly.toml, making migration trickier.

Feature Comparison

Performance

From what I've seen, Fly.io wins on raw global performance because it distributes containers. Coolify's performance depends entirely on where you host your servers—if you're okay with a single region, it can be fast, but latency varies.

Developer Experience

Coolify feels familiar if you're used to Docker; setting it up on a VPS is straightforward. Fly.io, with its CLI and fly.toml, has a steeper curve but offers powerful tools like preview deployments and rollbacks.

Pricing

Coolify: Free when self-hosted on your infra, or $5/month for managed options. Your main cost is the server. Fly.io: Free tier includes 3 shared-cpu machines with 256MB RAM each and data limits. Paid is usage-based, billed per-second, which can add up for high-traffic apps.

When to Choose Coolify

Choose Coolify if:

• You have existing servers or a tight budget and want to maximize control.
• Your app is full-stack with databases, and you prefer Docker workflows.
• You're avoiding cloud vendor lock-in and value open-source flexibility.
• Example: A side project where you're hosting on a $5/month VPS.

When to Choose Fly.io

Choose Fly.io if:

• Your app needs to be globally distributed for low latency, like a real-time chat app.
• You're working with AI/ML and require GPU support for inference.
• You want managed infrastructure with features like edge functions and analytics.
• Example: A Next.js app with users spread across continents.

Code Comparison: Deploying a Simple Node.js App

Here’s how a basic deployment looks side-by-side. First, Coolify (assuming you've set it up on a server):

# docker-compose.yml for Coolify (simplified)
version: '3.8'
services:
  app:
    image: node:18-alpine
    ports:
      - "3000:3000"
    volumes:
      - ./app:/usr/src/app
    command: npm start

In Coolify, you'd upload this via the UI or CLI to your self-hosted instance.

Now, Fly.io:

# fly.toml for Fly.io
app = "your-app-name"
primary_region = "iad"  # Example: Virginia

[[services]]
  internal_port = 3000
  protocol = "tcp"

  [[services.ports]]
    port = 80
    handlers = ["http"]
    [[services.ports.tls_options]]
      alpn = ["h2", "http/1.1"]

With Fly.io, you run fly launch and it handles the rest. The key difference: Coolify needs your server setup, while Fly.io abstracts it away.

Migration: Switching Between Them

Switching isn't trivial but doable. From Coolify to Fly.io, you'd containerize your app (if not already) and adapt configs to fly.toml. From Fly.io to Coolify, you'd need to set up a server and move Docker images. In both cases, expect some reconfiguration and testing—it's similar to moving between any PaaS.

Frequently Asked Questions

FAQ: Which one is better for beginners?

If you're new, Coolify might be easier if you're comfortable with Docker basics and have a server ready. Fly.io's CLI can be intimidating, but its docs are solid. From my experience, start with Coolify for small self-hosted projects to learn the ropes.

FAQ: Can I switch from Coolify to Fly.io later?

Yes, but it involves work. You'll need to ensure your app is containerized (Coolify uses Docker, so that helps), then reconfigure for Fly.io's platform. It's not a one-click move, but doable with some effort.

FAQ: Which one is cheaper for small projects?

For very low traffic, Coolify on a cheap VPS (like $5/month) can be cheaper since Fly.io's free tier has limits. But if you stay within Fly.io's free limits, it might cost nothing. Weigh your traffic and storage needs.

FAQ: Do both support Next.js?

Yes, both support SSR, ISR, and related features. Coolify handles it via Docker containers, while Fly.io has built-in optimizations for frameworks like Next.js, making deployment smoother.

FAQ: Which one has better performance?

Fly.io generally offers better global performance due to edge distribution. Coolify's performance depends on your server location—if you host centrally, it's fine, but for global users, Fly.io wins.

FAQ: Can I use both together?

Possibly, but it adds complexity. For example, use Coolify for a backend database on your server and Fly.io for a globally distributed frontend. However, you'd manage two platforms, which might not be worth it for most projects.

FAQ: Is there a clear winner in Coolify vs Fly.io 2026?

Nope, and that's the point. It depends on your priorities: control and cost (Coolify) vs. convenience and performance (Fly.io). Both are great tools; pick based on your specific needs.

Conclusion

So, when deciding between Coolify and Fly.io, think about what matters most for your project. If you're all about self-hosting and keeping costs down, give Coolify a shot. But if you need that global edge and don't mind the learning curve, Fly.io is worth the investment. Test both with their free tiers—you might find one just clicks with your workflow. Happy deploying!

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Last updated: 2026-01-07