aws-transform-modernization

Miru for modernization assessment

Use Miru MCP as the default code-exploration path when assessing a legacy or unfamiliar codebase for migration/modernization.

Miru supports a self-hosted SageMaker embedding backend instead of Takara-hosted — see docs/self-hosted-sagemaker.md and run miru setup --sagemaker to opt in. An endpoint and AWS identity are customer-specific, so this is not configured automatically.

When to use it

Use Miru when the task looks like:

• map dependencies for this module
• identify high-risk or high-complexity modules
• find all callers of this routine, and from where
• find everything related to this legacy interface, copybook, or subroutine
• what does this routine actually do, before porting it

For exact literal lookups, use locate instead of search:

• env var names
• exact error codes
• quoted string matches

Workflow

1. Call search once with repo set to the project root.
2. If a result has truncated: true, read the lines in its header (path:start-end Symbol) with a ranged read; use expand with file_path and anchor_line for neighbouring chunks.
3. Use find_related to find similar code patterns in other files (e.g. other copies of a legacy routine, parallel implementations). For callers and dependents, use search with the routine/interface name.
4. For exact literal lookups (env var names, error codes, quoted strings), use locate with mode=count or locations rather than search.
5. Read files directly only after Miru has already identified the relevant path.

Tool preference

• Prefer Miru search over grep/glob/bash exploration when mapping what a legacy module does.
• Prefer a ranged read of the hit's start-end lines (or Miru expand) over rereading whole files when a hit is truncated.
• Prefer Miru find_related over repeated search paraphrases when looking for similar code (other copies, parallel implementations) — cryptic legacy naming conventions make keyword search unreliable for this.
• Prefer Miru locate over grep for exact substrings — env vars, symbols, error codes — cryptic legacy naming makes keyword search unreliable here too, and locate is built for exact matches, not search.