Platform as a Service (PaaS) is a cloud computing model where a provider manages the underlying infrastructure — servers, storage, networking, operating system, and runtime — and you supply only your application code and data. It sits in the middle of the three cloud service models: with IaaS you manage more of the stack, and with SaaS you manage nothing at all. For most SaaS founders, PaaS is where the product first ships.
What Is PaaS?
PaaS gives developers a ready-to-use platform to build, run, and deploy applications without configuring the servers and system software underneath. You push your code; the provider handles the operating system, patching, scaling, and runtime.
The easiest way to place PaaS is the well-known "pizza as a service" analogy (created by Albert Barron of IBM in 2014):
| Model | Pizza analogy | You handle |
|---|---|---|
| On-premises | Homemade pizza | Everything — buy and make it all yourself |
| IaaS | Take-and-bake | Provider supplies the base; you bring the oven, table, drinks |
| PaaS | Pizza delivery | Arrives ready to eat; you just supply the table and drinks |
| SaaS | Dining out | Show up and eat — everything is handled |
IaaS vs PaaS vs SaaS: Who Manages What
The three cloud service models differ by how much of the stack the provider runs for you:
| Layer | On-prem | IaaS | PaaS | SaaS |
|---|---|---|---|---|
| Applications | You | You | You | Provider |
| Data | You | You | You | Provider |
| Runtime | You | You | Provider | Provider |
| Middleware | You | You | Provider | Provider |
| Operating system | You | You | Provider | Provider |
| Virtualization | You | Provider | Provider | Provider |
| Servers / storage / networking | You | Provider | Provider | Provider |
| You bring | everything | apps, data, OS, runtime | just code + data | nothing |
In short: with IaaS you rent raw compute and manage the OS up; with PaaS you manage only your code and data; with SaaS you just log in and use a finished app.
PaaS Examples
- Heroku — pioneered the
git pushdeploy model. Its free tier was removed on November 28, 2022; the cheapest paid option is now the Eco dyno at $5/mo. - Google App Engine — Google's hyperscaler PaaS, with standard and flexible environments.
- AWS Elastic Beanstalk — the PaaS layer on AWS (which is otherwise primarily IaaS); supports Node.js, Python, Ruby, Java, .NET, Go, PHP, and Docker.
- Azure App Service — Microsoft's full PaaS for web apps and APIs.
- Render and Fly.io — modern, container-based platforms, often described as the closest to the original Heroku experience.
- Vercel and Netlify — modern PaaS optimized for frontend and Jamstack apps.
- Red Hat OpenShift — enterprise, Kubernetes-based PaaS.
(This very blog runs on Cloudflare Pages — a modern PaaS-style platform — so the pattern is everywhere.)
When Does a SaaS Founder Actually Use PaaS?
Nearly always, at the start. Most early-stage SaaS products deploy on a PaaS (Heroku, Render, Vercel, Fly.io) precisely because it removes infrastructure work — you ship features instead of configuring servers. The build-vs-buy decision here is really speed-vs-control: PaaS buys you speed, at a per-unit cost premium.
Many teams later migrate to raw IaaS (like AWS EC2) as they scale — not because PaaS stops working, but because the convenience premium starts to bite the margin. That migration is a financial decision as much as a technical one.
PaaS in Your Cost Stack
For a founder, PaaS isn't just architecture — it's a line on the P&L:
- PaaS fees are a classic COGS line. Hosting and infrastructure are the cost of delivering your service, so they sit in cost of goods sold.
- They erode gross margin as you scale. The PaaS convenience premium is cheap when you're small and expensive when you're big — which is exactly why teams migrate off Heroku to AWS at scale.
- They turn CapEx into OpEx. Instead of capitalizing servers, PaaS/IaaS make infrastructure a pay-as-you-go operating expense — contrast this with capitalized software development.
The trade-off in one line: PaaS ships faster at a higher per-unit cost; IaaS is cheaper at scale but demands engineering overhead. Model it, don't default to it.
PaaS Advantages and Disadvantages
| Advantages | Disadvantages |
|---|---|
| Faster development (skip infra setup) | Vendor lock-in — hard to migrate off |
| Pay-as-you-go pricing | Limited low-level control and customization |
| Automatic updates, patching, security | Integration friction with legacy/on-prem systems |
| Built-in scaling and collaboration | Cost creep at scale (the convenience premium) |
Vendor lock-in is the headline risk: once your app is built around a platform's runtime and services, moving is real work.
PaaS FAQ
What is PaaS in simple terms?
PaaS (Platform as a Service) is a cloud service where the provider runs the servers, operating system, and runtime, and you supply only your application code and data. Heroku and Google App Engine are common examples — you push code and the platform runs it.
What is an example of Platform as a Service?
Heroku, Google App Engine, AWS Elastic Beanstalk, Azure App Service, Render, and Vercel are all PaaS platforms. Each lets developers deploy apps without managing the underlying servers or operating system.
What is the difference between PaaS and SaaS?
PaaS gives developers a platform to build and deploy their own applications; SaaS delivers a finished application ready for end users. You manage your code and data on PaaS, and manage nothing on SaaS.
What is the difference between IaaS, PaaS, and SaaS?
They differ by how much the provider manages. IaaS provides raw infrastructure (you handle the OS and up), PaaS adds the OS, middleware, and runtime (you handle just code and data), and SaaS delivers a complete application (you handle nothing).
Is AWS a PaaS?
AWS is primarily an IaaS provider, but it offers PaaS through services like Elastic Beanstalk. As a whole, AWS spans all three cloud models.
Is Salesforce PaaS or SaaS?
Both. Salesforce is a SaaS product (its CRM), and it also offers the Salesforce Platform — a PaaS layer for building custom apps on its infrastructure.
What are the disadvantages of PaaS?
The main drawbacks are vendor lock-in, limited low-level control, integration friction with legacy systems, and rising cost at scale as the convenience premium adds up.
Do SaaS companies use PaaS?
Yes. Most early-stage SaaS deploys on a PaaS to ship quickly, then some migrate to raw IaaS as scale makes the per-unit cost worth the extra engineering. It's a recurring build-vs-buy decision as the company grows.
