IMPACT

IMPACT is an experimental CLI for assessing the environmental impact of Scaleway infrastructure from two sources: Terraform plans (forecast) and Scaleway APIs (measured data).

It reports monthly impact focused on carbon emissions (kgCO2e) and water consumption (m3).

Estimated monthly impact badge (from Terraform plan). Setup and generation details: docs/badges.md.

⚠️ Proof-of-concept tool under development
This project is unofficial and not affiliated with or endorsed by Scaleway.
impact uses Scaleway Environmental Footprint APIs that are currently in alpha, and plan results rely on Terraform-to-SKU mapping logic and catalog metadata.
Do not use this output as a compliance source of truth.

Commands

• impact plan - estimate impact from Terraform plans
• impact actual - query measured footprint from Scaleway APIs
• impact doctor - check environment/auth and API reachability
• impact completion - generate shell completions

Use help at any level:

impact --help
impact plan --help
impact actual --help
impact doctor --help

Screenshots

1) CLI output

2) TUI output

What It Is For

• review infrastructure changes before terraform apply
• compare estimated (plan) vs measured (actual) impact
• export table or JSON output for reviews and reporting

Installation

Build locally:

go build -o impact ./cmd/impact

Install from GitHub:

go install github.com/alesr/impact/cmd/impact@latest

Requirements

• Go 1.25+
• Terraform 1.6+ for plan workflows
• Scaleway credentials for API-backed commands

Environment Variables

Variable	Used by	Notes
SCW_ACCESS_KEY	impact actual, impact doctor, Terraform provider	API access key
SCW_SECRET_KEY	impact actual, impact doctor, Terraform provider	API secret key/token
SCW_ORGANIZATION_ID	impact actual, impact doctor	Organization UUID
IMPACT_SCW_API_BASE_URL	API-backed commands	Optional base URL override (default https://api.scaleway.com)

Quick Start

1) Forecast from Terraform plan JSON

Before running, set real values for db_password and redis_password in examples/terraform.tfvars.example.

terraform -chdir=examples init
terraform -chdir=examples plan -var-file=terraform.tfvars.example -out=tfplan
terraform -chdir=examples show -json tfplan > examples/tfplan.json

impact plan --file examples/tfplan.json --format table

TUI mode:

impact plan --file examples/tfplan.json --tui

Directly from Terraform (run inside your Terraform directory):

impact plan --from-terraform --format table

2) Query measured impact

export SCW_SECRET_KEY="..."
export SCW_ORGANIZATION_ID="..."
export SCW_ACCESS_KEY="SCWXXXXXXXXXXXXXXXXX"

impact actual --start 2026-01-01 --end 2026-01-31 --format table

Optional filters:

• --project
• --region
• --zone
• --service-category
• --product-category

Accepted values:

• service categories: baremetal, compute, storage
• product categories: applesilicon, blockstorage, dedibox, elasticmetal, instances, objectstorage

Filter value normalization is supported, so separators like -, _, and spaces are accepted (for example apple-silicon, apple_silicon, apple silicon).

3) Run diagnostics

impact doctor

doctor checks:

• config/env visibility
• catalog endpoint reachability
• footprint query reachability (when auth and org are present)

Plan Estimation Semantics

impact plan estimates monthly deltas with action-aware behavior:

• create: adds estimated monthly impact
• delete: subtracts estimated monthly impact
• update: estimates delta as before vs after (old config subtracted, new config added)
• replace (delete + create): modeled as delete + create transitions

Notes:

• N/A means footprint data is missing for a mapped product, not zero impact.
• totals can be partial when one or more rows have unknown footprint values.

Showcase Configuration

Files:

• examples/showcase.tf
• examples/terraform.tfvars.example

Showcase includes:

• instance server replicas and block volume
• load balancer
• rdb and redis
• intentionally unsupported resources (scaleway_instance_ip, scaleway_vpc_private_network) to demonstrate diagnostics output

Example run from repo root:

terraform -chdir=examples init
terraform -chdir=examples plan -var-file=terraform.tfvars.example -out=tfplan
terraform -chdir=examples show -json tfplan > examples/tfplan.json

impact plan --file examples/tfplan.json --format table

# optional TUI view
impact plan --file examples/tfplan.json --tui

Development

Run tests:

go test ./...

For local development without installing the binary:

go run ./cmd/impact --help

Links

Topic	Link
Environmental Footprint docs	https://www.scaleway.com/en/docs/environmental-footprint/
Environmental Footprint integration guide	https://www.scaleway.com/en/docs/environmental-footprint/additional-content/environmental-footprint-integration/
Environmental Footprint User API	https://www.scaleway.com/en/developers/api/environmental-footprint/user-api/
Product Catalog Public Catalog API	https://www.scaleway.com/en/developers/api/product-catalog/public-catalog-api/
Scaleway Go SDK	https://github.com/scaleway/scaleway-sdk-go