Monorepos¶

Using TerraTidy in repositories with multiple Terraform modules.

Setup¶

Initialize a monorepo configuration:

terratidy init --monorepo

This creates a .terratidy.yaml with:

Central ./policies directory for shared OPA policies
ci profile (all engines enabled)
development profile (lint and policy disabled for speed)

Config Placement¶

Place .terratidy.yaml at the repository root. TerraTidy processes files relative to the current working directory:

repo/
  .terratidy.yaml          # Root config
  policies/                # Shared OPA policies
  modules/
    networking/
      main.tf
      variables.tf
    compute/
      main.tf
      variables.tf
  environments/
    staging/
      main.tf
    production/
      main.tf

Running Checks¶

Specific modules¶

terratidy check ./modules/networking
terratidy check ./modules/compute

All modules¶

terratidy check ./modules ./environments

Changed files only¶

terratidy check --changed

This checks all modified .tf/.hcl/.tfvars files across the entire repo.

Profile-Based Workflows¶

Local development (fast)¶

terratidy check --profile development

CI/CD (thorough)¶

terratidy check --profile ci --parallel

Production deployment gate¶

terratidy check --profile ci --severity-threshold error

Module Overrides¶

Override rules for specific modules using config imports:

# .terratidy.yaml
version: 1

imports:
  - ./modules/networking/.terratidy-overrides.yaml

engines:
  style:
    enabled: true

# modules/networking/.terratidy-overrides.yaml
overrides:
  rules:
    style.terraform-files-structure:
      enabled: false  # Networking module uses a different structure

CI Integration¶

Run checks per module in parallel CI jobs:

# GitHub Actions
strategy:
  matrix:
    module: [networking, compute, database, iam]

steps:
  - uses: actions/checkout@v4
  - uses: santosr2/terratidy@v0
    with:
      working-directory: modules/${{ matrix.module }}
      profile: ci