Cloudformation To Pulumi
PulumiOfficialPublished by Pulumi
- Skill
- Workflow
- Cloud and DevOps
- Apache-2.0
- No issues found
AutoGineer summary
Written by AutoGineer from the skill’s own files, not by the author
This skill provides a rigorous, step-by-step procedure for converting AWS CloudFormation templates into Pulumi programs. It emphasizes the use of the aws-native provider and strict adherence to CloudFormation Logical IDs to facilitate automated resource imports. The process covers information gathering, manual code conversion, handling of intrinsic functions, and post-import validation to ensure a zero-diff state between the existing stack and the new Pulumi-managed infrastructure.
What it does
- Extracts resource inventories and templates from existing AWS CloudFormation stacks.
- Maps CloudFormation intrinsic functions and parameters to their Pulumi TypeScript equivalents.
- Enforces the use of CloudFormation Logical IDs as Pulumi resource names for automated import compatibility.
- Prioritizes the aws-native provider to ensure structural alignment with CloudFormation types.
- Provides a template for a formal migration report suitable for pull requests.
- Guides users through the post-import validation process to ensure no unexpected infrastructure changes occur.
When to use it
- When you need to migrate existing AWS CloudFormation stacks to Pulumi.
- When you have a CloudFormation template and need to generate equivalent Pulumi code.
- When you need to import existing AWS resources managed by CloudFormation into a Pulumi project.
- When you are using cdk-importer and need to ensure your Pulumi code is correctly structured for automated matching.
Advantages
- Ensures structural consistency between legacy CloudFormation and new Pulumi code.
- Reduces manual effort during the import phase by leveraging Logical ID naming conventions.
- Provides a clear, repeatable workflow for complex infrastructure migrations.
- Minimizes the risk of drift or unintended resource replacement during the transition.
Usage examples
- “I want to migrate my production CloudFormation stack named 'web-app-prod' to Pulumi. How do I start?”
- The agent will guide you through verifying your AWS credentials, fetching the template, building a resource inventory, and beginning the manual conversion process using the required naming conventions.
- “How do I map my CloudFormation !Sub and !GetAtt functions to Pulumi?”
- The agent will provide specific TypeScript patterns, such as using pulumi.interpolate for !Sub and direct property access for !GetAtt, ensuring your code is ready for import.
Install
Download the skill as a ZIP:
https://mp-staging.autogineer.com/agent-skills/pulumi/cloudformation-to-pulumi/downloadUnzip it into the cross-client skills folder of your project:
mkdir -p .agents/skills && unzip cloudformation-to-pulumi.zip -d .agents/skills
Documentation by Pulumi
IMPORTANT: PLAN ADJUSTMENT REQUIRED
If you have already generated a migration plan before loading this skill, you MUST:
Review your existing plan against the workflows and requirements in this skill
Identify any gaps, missing steps, or incorrect assumptions
Update and revise your plan to align with this skill's guidance
Communicate the adjusted plan to the user before proceeding
CRITICAL SUCCESS REQUIREMENTS
The migration output MUST meet all of the following:
Complete Resource Coverage
Every CloudFormation resource MUST be represented in the Pulumi program OR explicitly justified in the final report.
CloudFormation Logical ID as Resource Name
CRITICAL: Every Pulumi resource MUST use the CloudFormation Logical ID as its resource name.
This enables the
cdk-importertool to automatically find import IDs.DO NOT rename resources. Automated import will FAIL if you change the logical IDs.
Successful Deployment
The produced Pulumi program must be structurally valid and capable of a successful
pulumi preview(assuming proper config).
Zero-Diff Import Validation (if importing existing resources)
After import,
pulumi previewmust show NO updates, replaces, creates, or deletes.
Final Migration Report
Always output a formal migration report suitable for a Pull Request.
WHEN INFORMATION IS MISSING
If the user has not provided a CloudFormation template, you MUST fetch it from AWS using the stack name.
MIGRATION WORKFLOW
Follow this workflow exactly and in this order:
1. INFORMATION GATHERING
1.1 Verify AWS Credentials (ESC)
Running AWS commands requires credentials loaded via Pulumi ESC.
If the user has already provided an ESC environment, use it.
If no ESC environment is specified, ask the user which ESC environment to use before proceeding.
For detailed ESC information: Use skill pulumi-esc.
You MUST confirm the AWS region with the user.
1.2 Get the CloudFormation Template
If user provided a template file: Read the template directly.
If user only provided a stack name: Fetch the template from AWS:
aws cloudformation get-template \
--region <region> \
--stack-name <stack-name> \
--query 'TemplateBody' \
--output json > template.json1.3 Build Resource Inventory
List all resources in the stack:
aws cloudformation list-stack-resources \
--region <region> \
--stack-name <stack-name> \
--output jsonThis provides:
LogicalResourceId- Use this as the Pulumi resource namePhysicalResourceId- The actual AWS resource IDResourceType- The CloudFormation resource type
1.4 Analyze Template Structure
Extract from the template:
Parameters and their defaults
Mappings
Conditions
Outputs
Resource dependencies (Ref, GetAtt, DependsOn)
2. CODE CONVERSION (CloudFormation → Pulumi)
IMPORTANT: There is NO automated conversion tool for CloudFormation. You MUST convert each resource manually.
2.1 Resource Name Convention (CRITICAL)
Every Pulumi resource MUST use the CloudFormation Logical ID as its name.
// CloudFormation:
// "MyAppBucketABC123": { "Type": "AWS::S3::Bucket", ... }
// Pulumi - CORRECT:
const myAppBucket = new aws.s3.Bucket("MyAppBucketABC123", { ... });
// Pulumi - WRONG (DO NOT do this - import will fail):
const myAppBucket = new aws.s3.Bucket("my-app-bucket", { ... });This naming convention is REQUIRED because the cdk-importer tool matches resources by name.
2.2 Provider Strategy
⚠️ CRITICAL: ALWAYS USE aws-native BY DEFAULT ⚠️
Use
aws-nativefor all resources unless there's a specific reason to useaws.CloudFormation types map directly to aws-native (e.g.,
AWS::S3::Bucket→aws-native.s3.Bucket).Only use
aws(classic) when aws-native doesn't support a required feature.
This is MANDATORY for successful imports with cdk-importer. The cdk-importer works by matching CloudFormation resources to Pulumi resources, and CloudFormation maps 1:1 to aws-native. Using the classic aws provider will cause import failures.
2.3 CloudFormation Intrinsic Functions
Map CloudFormation intrinsic functions to Pulumi equivalents:
| CloudFormation | Pulumi Equivalent |
|---|---|
!Ref (resource) | Resource output (e.g., bucket.id) |
!Ref (parameter) | Pulumi config |
!GetAtt Resource.Attr | Resource property output |
!Sub "..." | pulumi.interpolate |
!Join [delim, [...]] | pulumi.interpolate or .apply() |
!If [cond, true, false] | Ternary operator |
!Equals [a, b] | === comparison |
!Select [idx, list] | Array indexing with .apply() |
!Split [delim, str] | .apply(v => v.split(...)) |
Fn::ImportValue | Stack references or config |
Example: !Sub
// CloudFormation: !Sub "arn:aws:s3:::${MyBucket}/*"
// Pulumi:
const bucketArn = pulumi.interpolate`arn:aws:s3:::${myBucket.bucket}/*`;Example: !GetAtt
// CloudFormation: !GetAtt MyFunction.Arn
// Pulumi:
const functionArn = myFunction.arn;2.4 CloudFormation Conditions
Convert CloudFormation conditions to TypeScript logic:
// CloudFormation:
// "Conditions": {
// "CreateProdResources": { "Fn::Equals": [{ "Ref": "Environment" }, "prod"] }
// }
// Pulumi:
const config = new pulumi.Config();
const environment = config.require("environment");
const createProdResources = environment === "prod";
if (createProdResources) {
// Create production-only resources
}2.5 CloudFormation Parameters
Convert parameters to Pulumi config:
// CloudFormation:
// "Parameters": {
// "InstanceType": { "Type": "String", "Default": "t3.micro" }
// }
// Pulumi:
const config = new pulumi.Config();
const instanceType = config.get("instanceType") || "t3.micro";2.6 CloudFormation Mappings
Convert mappings to TypeScript objects:
// CloudFormation:
// "Mappings": {
// "RegionMap": {
// "us-east-1": { "AMI": "ami-12345" },
// "us-west-2": { "AMI": "ami-67890" }
// }
// }
// Pulumi:
const regionMap: Record<string, { ami: string }> = {
"us-east-1": { ami: "ami-12345" },
"us-west-2": { ami: "ami-67890" },
};
const ami = regionMap[aws.config.region!].ami;2.7 Custom Resources
CloudFormation Custom Resources (AWS::CloudFormation::CustomResource or Custom::*) require special handling:
Identify the purpose: Read the Lambda function code to understand what it does
Find native replacement: Check if Pulumi has a native resource that provides the same functionality
If no replacement: Document in the migration report that manual implementation is needed
2.8 TypeScript Output Handling
aws-native outputs often include undefined. Avoid ! non-null assertions. Always safely unwrap with .apply():
// WRONG
functionName: lambdaFunction.functionName!,
// CORRECT
functionName: lambdaFunction.functionName.apply(name => name || ""),3. RESOURCE IMPORT
After conversion, import existing resources to be managed by Pulumi.
3.0 Pre-Import Validation (REQUIRED)
Before proceeding with import, verify your code:
Check Provider Usage: Scan your code to ensure all resources use
aws-nativeDocument Exceptions: Any use of
aws(classic) provider must be justifiedVerify Resource Names: Confirm all resources use CloudFormation Logical IDs as names
3.1 Automated Import with cdk-importer
Because you used CloudFormation Logical IDs as resource names, you can use the cdk-importer tool to automatically import resources.
Follow cfn-importer.md for detailed import procedures.
3.2 Manual Import for Failed Resources
For resources that fail automatic import:
Follow cloudformation-id-lookup.md to find the import ID format
Use
pulumi import:
pulumi import <pulumi-resource-type> <logical-id> <import-id>3.3 Running Preview After Import
After import, run pulumi preview. There must be:
NO updates
NO replaces
NO creates
NO deletes
If there are changes, investigate and update the program until preview is clean.
OUTPUT FORMAT (REQUIRED)
When performing a migration, always produce:
Overview (high-level description)
Migration Plan Summary
Pulumi Code Outputs (TypeScript; organized by file)
Resource Mapping Table:
| CloudFormation Logical ID | CFN Type | Pulumi Type | Provider |
|---|---|---|---|
MyAppBucketABC123 | AWS::S3::Bucket | aws-native.s3.Bucket | aws-native |
MyLambdaFunction456 | AWS::Lambda::Function | aws-native.lambda.Function | aws-native |
Custom Resources Summary (if any)
Final Migration Report (PR-ready)
Next Steps (import instructions)
FOR DETAILED DOCUMENTATION
Fetch content from official Pulumi documentation:
Files
- ATTRIBUTION.mdAdded by AutoGineer882 B
- LICENSELicence file added by AutoGineer11.1 KiB
- SKILL.md9.4 KiB
- agents/openai.yaml249 B
- cfn-importer.md4.2 KiB
- cloudformation-id-lookup.md2.8 KiB
- use_cases.yaml801 B
LICENSE
Apache License
Version 2.0, January 2004
http://www.apache.org/licenses/
TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
1. Definitions.
"License" shall mean the terms and conditions for use, reproduction,
and distribution as defined by Sections 1 through 9 of this document.
"Licensor" shall mean the copyright owner or entity authorized by
the copyright owner that is granting the License.
"Legal Entity" shall mean the union of the acting entity and all
other entities that control, are controlled by, or are under common
control with that entity. For the purposes of this definition,
"control" means (i) the power, direct or indirect, to cause the
direction or management of such entity, whether by contract or
otherwise, or (ii) ownership of fifty percent (50%) or more of the
outstanding shares, or (iii) beneficial ownership of such entity.
"You" (or "Your") shall mean an individual or Legal Entity
exercising permissions granted by this License.
"Source" form shall mean the preferred form for making modifications,
including but not limited to software source code, documentation
source, and configuration files.
"Object" form shall mean any form resulting from mechanical
transformation or translation of a Source form, including but
not limited to compiled object code, generated documentation,
and conversions to other media types.
"Work" shall mean the work of authorship, whether in Source or
Object form, made available under the License, as indicated by a
copyright notice that is included in or attached to the work
(an example is provided in the Appendix below).
"Derivative Works" shall mean any work, whether in Source or Object
form, that is based on (or derived from) the Work and for which the
editorial revisions, annotations, elaborations, or other modifications
represent, as a whole, an original work of authorship. For the purposes
of this License, Derivative Works shall not include works that remain
separable from, or merely link (or bind by name) to the interfaces of,
the Work and Derivative Works thereof.
"Contribution" shall mean any work of authorship, including
the original version of the Work and any modifications or additions
to that Work or Derivative Works thereof, that is intentionally
submitted to Licensor for inclusion in the Work by the copyright owner
or by an individual or Legal Entity authorized to submit on behalf of
the copyright owner. For the purposes of this definition, "submitted"
means any form of electronic, verbal, or written communication sent
to the Licensor or its representatives, including but not limited to
communication on electronic mailing lists, source code control systems,
and issue tracking systems that are managed by, or on behalf of, the
Licensor for the purpose of discussing and improving the Work, but
excluding communication that is conspicuously marked or otherwise
designated in writing by the copyright owner as "Not a Contribution."
"Contributor" shall mean Licensor and any individual or Legal Entity
on behalf of whom a Contribution has been received by Licensor and
subsequently incorporated within the Work.
2. Grant of Copyright License. Subject to the terms and conditions of
this License, each Contributor hereby grants to You a perpetual,
worldwide, non-exclusive, no-charge, royalty-free, irrevocable
copyright license to reproduce, prepare Derivative Works of,
publicly display, publicly perform, sublicense, and distribute the
Work and such Derivative Works in Source or Object form.
3. Grant of Patent License. Subject to the terms and conditions of
this License, each Contributor hereby grants to You a perpetual,
worldwide, non-exclusive, no-charge, royalty-free, irrevocable
(except as stated in this section) patent license to make, have made,
use, offer to sell, sell, import, and otherwise transfer the Work,
where such license applies only to those patent claims licensable
by such Contributor that are necessarily infringed by their
Contribution(s) alone or by combination of their Contribution(s)
with the Work to which such Contribution(s) was submitted. If You
institute patent litigation against any entity (including a
cross-claim or counterclaim in a lawsuit) alleging that the Work
or a Contribution incorporated within the Work constitutes direct
or contributory patent infringement, then any patent licenses
granted to You under this License for that Work shall terminate
as of the date such litigation is filed.
4. Redistribution. You may reproduce and distribute copies of the
Work or Derivative Works thereof in any medium, with or without
modifications, and in Source or Object form, provided that You
meet the following conditions:
(a) You must give any other recipients of the Work or
Derivative Works a copy of this License; and
(b) You must cause any modified files to carry prominent notices
stating that You changed the files; and
(c) You must retain, in the Source form of any Derivative Works
that You distribute, all copyright, patent, trademark, and
attribution notices from the Source form of the Work,
excluding those notices that do not pertain to any part of
the Derivative Works; and
(d) If the Work includes a "NOTICE" text file as part of its
distribution, then any Derivative Works that You distribute must
include a readable copy of the attribution notices contained
within such NOTICE file, excluding those notices that do not
pertain to any part of the Derivative Works, in at least one
of the following places: within a NOTICE text file distributed
as part of the Derivative Works; within the Source form or
documentation, if provided along with the Derivative Works; or,
within a display generated by the Derivative Works, if and
wherever such third-party notices normally appear. The contents
of the NOTICE file are for informational purposes only and
do not modify the License. You may add Your own attribution
notices within Derivative Works that You distribute, alongside
or as an addendum to the NOTICE text from the Work, provided
that such additional attribution notices cannot be construed
as modifying the License.
You may add Your own copyright statement to Your modifications and
may provide additional or different license terms and conditions
for use, reproduction, or distribution of Your modifications, or
for any such Derivative Works as a whole, provided Your use,
reproduction, and distribution of the Work otherwise complies with
the conditions stated in this License.
5. Submission of Contributions. Unless You explicitly state otherwise,
any Contribution intentionally submitted for inclusion in the Work
by You to the Licensor shall be under the terms and conditions of
this License, without any additional terms or conditions.
Notwithstanding the above, nothing herein shall supersede or modify
the terms of any separate license agreement you may have executed
with Licensor regarding such Contributions.
6. Trademarks. This License does not grant permission to use the trade
names, trademarks, service marks, or product names of the Licensor,
except as required for reasonable and customary use in describing the
origin of the Work and reproducing the content of the NOTICE file.
7. Disclaimer of Warranty. Unless required by applicable law or
agreed to in writing, Licensor provides the Work (and each
Contributor provides its Contributions) on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
implied, including, without limitation, any warranties or conditions
of TITLE, NON-INFRINGEMENT, MERCHANTABILITY, or FITNESS FOR A
PARTICULAR PURPOSE. You are solely responsible for determining the
appropriateness of using or redistributing the Work and assume any
risks associated with Your exercise of permissions under this License.
8. Limitation of Liability. In no event and under no legal theory,
whether in tort (including negligence), contract, or otherwise,
unless required by applicable law (such as deliberate and grossly
negligent acts) or agreed to in writing, shall any Contributor be
liable to You for damages, including any direct, indirect, special,
incidental, or consequential damages of any character arising as a
result of this License or out of the use or inability to use the
Work (including but not limited to damages for loss of goodwill,
work stoppage, computer failure or malfunction, or any and all
other commercial damages or losses), even if such Contributor
has been advised of the possibility of such damages.
9. Accepting Warranty or Additional Liability. While redistributing
the Work or Derivative Works thereof, You may choose to offer,
and charge a fee for, acceptance of support, warranty, indemnity,
or other liability obligations and/or rights consistent with this
License. However, in accepting such obligations, You may act only
on Your own behalf and on Your sole responsibility, not on behalf
of any other Contributor, and only if You agree to indemnify,
defend, and hold each Contributor harmless for any liability
incurred by, or claims asserted against, such Contributor by reason
of your accepting any such warranty or additional liability.
END OF TERMS AND CONDITIONS
APPENDIX: How to apply the Apache License to your work.
To apply the Apache License to your work, attach the following
boilerplate notice, with the fields enclosed by brackets "[]"
replaced with your own identifying information. (Don't include
the brackets!) The text should be enclosed in the appropriate
comment syntax for the file format. We also recommend that a
file or class name and description of purpose be included on the
same "printed page" as the copyright notice for easier
identification within third-party archives.
Copyright [yyyy] [name of copyright owner]
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
Requirements and compatibility
Works with: Claude Code, Claude apps, OpenAI Codex, GitHub Copilot, Cursor, Gemini CLI, Kiro, OpenCode, Goose, Amp, Roo Code, JetBrains Junie, Factory Droid, Devin (ex-Windsurf), Mistral Vibe, OpenHands, Letta
“Works with” means the tool reads the open Agent Skills format; a skill written for one tool may use features others lack.
Needs: Needs a command-line tool
Security
No issues found by our static scan· No issues found
A static scan is not a guarantee. Skills are third-party content: review a skill before you let an agent use it.
Attribution and licence
- Published by
- Pulumi
- Publisher
- Pulumi (Official)
- Source
- pulumi/agent-skills · migration/skills/cloudformation-to-pulumi · commit 82f222a
- Licence
- Apache License 2.0 (redistribution allowed)
- LICENSE (added by AutoGineer from LICENSE)
- ATTRIBUTION.md (written by AutoGineer)
- Synced
AutoGineer is not affiliated with or endorsed by Pulumi.
Download ZIP
The ZIP holds the skill’s files, its licence files and an ATTRIBUTION.md. Download cloudformation-to-pulumi.zip