How to use Pulumi instead of Terraform?

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Accepted Answer

**Pulumi** — IaC using programming languages (TypeScript, Python, Go, C#).

**Advantages over Terraform:**
- Real language (conditions, loops, functions).
- Type safety.
- Testing (unit tests).

**TypeScript example:**
```typescript
import * as aws from "@pulumi/aws";
import * as pulumi from "@pulumi/pulumi";

const vpc = new aws.ec2.Vpc("main", {
  cidrBlock: "10.0.0.0/16",
  tags: { Name: "production-vpc" },
});

const subnet = new aws.ec2.Subnet("public", {
  vpcId: vpc.id,
  cidrBlock: "10.0.1.0/24",
  availabilityZone: "us-east-1a",
  mapPublicIpOnLaunch: true,
});

const instance = new aws.ec2.Instance("web", {
  ami: "ami-xxx",
  instanceType: "t3.micro",
  subnetId: subnet.id,
  tags: { Name: "web-server" },
});

export const instanceIp = instance.publicIp;
```

**Dynamic logic:**
```typescript
const env = pulumi.getStack();
const instanceType = env === "production" ? "t3.large" : "t3.micro";

const instances = [];
for (let i = 0; i < (env === "production" ? 3 : 1); i++) {
  instances.push(new aws.ec2.Instance(`web-${i}`, {
    ami: "ami-xxx",
    instanceType,
  }));
}
```

**CLI:**
```bash
pulumi up       # apply
pulumi preview   # plan
pulumi destroy   # destroy
pulumi stack output  # outputs
```

**Pulumi vs Terraform:** Pulumi for complex logic (conditions, loops). Terraform simpler for simple configurations.

DevOps: How to use Pulumi instead of Terraform?