Terraform vs Pulumi in 2026: Which IaC Tool Should You Choose?

The Infrastructure as Code landscape has matured. Terraform dominates with market share, but Pulumi is winning converts with its programming language approach. Here’s an honest comparison to help you decide.

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The Core Difference

Terraform: Uses HCL (HashiCorp Configuration Language), a declarative DSL designed specifically for infrastructure.

Pulumi: Uses real programming languages (TypeScript, Python, Go, C#, Java) with full IDE support.

This isn’t just syntax — it fundamentally changes how you write and maintain infrastructure code.

Quick Comparison

Syntax Comparison

Let’s deploy the same infrastructure — an AWS Lambda function with an API Gateway.

Terraform Version

# providers.tf
terraform {
  required_providers {
    aws = {
      source  = "hashicorp/aws"
      version = "~> 5.0"
    }
  }
}

provider "aws" {
  region = var.region
}

# variables.tf
variable "region" {
  default = "us-east-1"
}

variable "environment" {
  type = string
}

# lambda.tf
resource "aws_iam_role" "lambda_role" {
  name = "api-lambda-role-${var.environment}"
  
  assume_role_policy = jsonencode({
    Version = "2012-10-17"
    Statement = [{
      Action = "sts:AssumeRole"
      Effect = "Allow"
      Principal = {
        Service = "lambda.amazonaws.com"
      }
    }]
  })
}

resource "aws_lambda_function" "api" {
  filename         = "lambda.zip"
  function_name    = "api-handler-${var.environment}"
  role            = aws_iam_role.lambda_role.arn
  handler         = "index.handler"
  runtime         = "nodejs20.x"
  source_code_hash = filebase64sha256("lambda.zip")
  
  environment {
    variables = {
      ENVIRONMENT = var.environment
    }
  }
}

resource "aws_apigatewayv2_api" "api" {
  name          = "api-${var.environment}"
  protocol_type = "HTTP"
}

resource "aws_apigatewayv2_integration" "lambda" {
  api_id           = aws_apigatewayv2_api.api.id
  integration_type = "AWS_PROXY"
  integration_uri  = aws_lambda_function.api.invoke_arn
}

resource "aws_apigatewayv2_route" "default" {
  api_id    = aws_apigatewayv2_api.api.id
  route_key = "ANY /{proxy+}"
  target    = "integrations/${aws_apigatewayv2_integration.lambda.id}"
}

resource "aws_lambda_permission" "api" {
  statement_id  = "AllowAPIGateway"
  action        = "lambda:InvokeFunction"
  function_name = aws_lambda_function.api.function_name
  principal     = "apigateway.amazonaws.com"
  source_arn    = "${aws_apigatewayv2_api.api.execution_arn}/*/*"
}

# outputs.tf
output "api_url" {
  value = aws_apigatewayv2_api.api.api_endpoint
}

Pulumi Version (TypeScript)

import * as pulumi from "@pulumi/pulumi";
import * as aws from "@pulumi/aws";

const config = new pulumi.Config();
const environment = config.require("environment");

// Lambda role
const lambdaRole = new aws.iam.Role("api-lambda-role", {
  assumeRolePolicy: JSON.stringify({
    Version: "2012-10-17",
    Statement: [{
      Action: "sts:AssumeRole",
      Effect: "Allow",
      Principal: { Service: "lambda.amazonaws.com" }
    }]
  })
});

// Lambda function
const lambda = new aws.lambda.Function("api-handler", {
  code: new pulumi.asset.FileArchive("lambda.zip"),
  role: lambdaRole.arn,
  handler: "index.handler",
  runtime: "nodejs20.x",
  environment: {
    variables: { ENVIRONMENT: environment }
  }
});

// API Gateway
const api = new aws.apigatewayv2.Api("api", {
  protocolType: "HTTP"
});

const integration = new aws.apigatewayv2.Integration("lambda-integration", {
  apiId: api.id,
  integrationType: "AWS_PROXY",
  integrationUri: lambda.invokeArn
});

const route = new aws.apigatewayv2.Route("default-route", {
  apiId: api.id,
  routeKey: "ANY /{proxy+}",
  target: pulumi.interpolate`integrations/${integration.id}`
});

new aws.lambda.Permission("api-permission", {
  action: "lambda:InvokeFunction",
  function: lambda.name,
  principal: "apigateway.amazonaws.com",
  sourceArn: pulumi.interpolate`${api.executionArn}/*/*`
});

export const apiUrl = api.apiEndpoint;

Photo by Ilya Pavlov on Unsplash

When Terraform Wins

1. Massive Ecosystem

4,000+ providers means virtually every cloud service is supported. Need to manage:

• Cloudflare DNS? ✓
• Datadog monitors? ✓
• GitHub repos? ✓
• PagerDuty schedules? ✓

Pulumi can use Terraform providers via a bridge, but native support is always smoother.

2. Hiring and Knowledge

Most DevOps engineers know Terraform. HCL is a common skill. Pulumi adoption is growing but still smaller.

Job listings (2026):
- "Terraform" — 45,000 results
- "Pulumi" — 8,000 results

3. Simplicity for Simple Infrastructure

For straightforward resources, HCL is often more concise:

# Terraform
resource "aws_s3_bucket" "logs" {
  bucket = "my-logs-bucket"
}

// Pulumi
const logs = new aws.s3.Bucket("logs", {
  bucket: "my-logs-bucket"
});

Similar length, but Terraform requires no build step or package management.

4. Policy as Code with Sentinel

HashiCorp Sentinel provides powerful governance:

# Require tags on all resources
main = rule {
  all tfplan.resources as _, resources {
    all resources as _, r {
      r.change.after.tags contains "Environment"
    }
  }
}

When Pulumi Wins

1. Complex Logic

Real programming languages handle complexity better:

// Dynamic resource creation based on config
const regions = ["us-east-1", "eu-west-1", "ap-southeast-1"];

const buckets = regions.map(region => {
  const provider = new aws.Provider(`provider-${region}`, { region });
  
  return new aws.s3.Bucket(`bucket-${region}`, {
    bucket: `my-app-${region}-${environment}`,
  }, { provider });
});

// Conditional resources
if (environment === "production") {
  new aws.cloudwatch.MetricAlarm("cpu-alarm", {
    // ... production monitoring
  });
}

The equivalent in Terraform requires count, for_each, and dynamic blocks — functional but awkward.

2. Type Safety and IDE Support

TypeScript catches errors before you apply:

const bucket = new aws.s3.Bucket("data", {
  acl: "private-read"  // ❌ IDE error: not a valid ACL value
});

With Terraform, you’d find this at terraform plan or worse, terraform apply.

3. Testing

Use your language’s native testing:

// Pulumi with Mocha/Jest
import * as pulumi from "@pulumi/pulumi";
import { expect } from "chai";

pulumi.runtime.setMocks({
  newResource: (type, name, inputs) => ({ id: name, state: inputs }),
  call: () => ({})
});

describe("Infrastructure", () => {
  it("should create bucket with encryption", async () => {
    const infra = await import("./index");
    const bucket = await infra.bucket;
    
    expect(bucket.serverSideEncryptionConfiguration).to.exist;
  });
});

4. Component Abstractions

Build reusable, typed components:

interface ApiServiceArgs {
  name: string;
  memory?: number;
  environment: Record<string, string>;
}

class ApiService extends pulumi.ComponentResource {
  public url: pulumi.Output<string>;
  
  constructor(name: string, args: ApiServiceArgs, opts?: pulumi.ComponentResourceOptions) {
    super("custom:ApiService", name, {}, opts);
    
    const lambda = new aws.lambda.Function(`${name}-function`, {
      memorySize: args.memory ?? 256,
      // ...
    }, { parent: this });
    
    // ... gateway setup
    
    this.url = gateway.apiEndpoint;
  }
}

// Usage
const userApi = new ApiService("user-api", {
  name: "users",
  memory: 512,
  environment: { DB_URL: dbUrl }
});

5. Secrets Management

Built-in encryption:

const config = new pulumi.Config();
const dbPassword = config.requireSecret("dbPassword");  // Auto-encrypted in state

new aws.rds.Instance("db", {
  password: dbPassword  // Stays encrypted
});

State Management Comparison

Terraform State

# Local state
terraform init

# Remote state (S3)
terraform {
  backend "s3" {
    bucket = "my-terraform-state"
    key    = "prod/terraform.tfstate"
    region = "us-east-1"
  }
}

Pulumi State

# Pulumi Cloud (default)
pulumi login

# Self-managed (S3)
pulumi login s3://my-pulumi-state

# Local
pulumi login --local

Both work well. Pulumi Cloud has better UI for state exploration. Terraform Cloud has more enterprise features.

Migration Path

Terraform to Pulumi

# Convert existing Terraform
pulumi convert --from terraform

# Import existing resources
pulumi import aws:s3/bucket:Bucket my-bucket my-bucket-name

Pulumi to Terraform

Export state and recreate manually. More painful — consider before starting.

Decision Framework

Choose Terraform if:

• Team has existing Terraform expertise
• Infrastructure is relatively straightforward
• You need maximum provider coverage
• Enterprise governance (Sentinel) is important
• Hiring DevOps engineers who know it

Choose Pulumi if:

• Team is developer-heavy (TypeScript, Python, Go)
• Complex logic and abstractions needed
• You want full IDE support and type safety
• Native testing is important
• Building internal platforms with reusable components

Consider Both:

• Use Terraform for core infrastructure (networking, databases)
• Use Pulumi for application-level infrastructure (serverless, containers)

Conclusion

There’s no wrong choice here. Both tools are mature, well-supported, and capable of managing production infrastructure at scale.

My take: If you’re starting fresh in 2026 and your team knows TypeScript or Python, give Pulumi a serious look. The developer experience is genuinely better for complex scenarios.

If you have existing Terraform and it works, there’s no urgent reason to switch. HCL isn’t going anywhere, and the ecosystem keeps growing.

The best IaC tool is the one your team will actually use consistently.

What’s your IaC stack? The infrastructure wars are far from over.

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