Legacy code often cannot build locally by nature — CICS/IMS programs
have no local translator and the real runtime may be a mainframe the
user doesn't have. Stopping transform on a failed legacy smoke compile
would block exactly those systems.
- transform Step 0a: the target toolchain remains required (its tests
cannot run without it); a failed or impossible legacy compile no
longer stops the run — the equivalence strategy switches to recorded
traces / golden-master fixtures, and that downgrade is stated in the
plan and in TRANSFORMATION_NOTES.md so reviewers know the strength of
the proof
- preflight: a red legacy toolchain now yields Ready-with-gaps for
transform/reimagine instead of Not-ready
The previous commit round-tripped the catalog through a JSON serializer,
which escaped non-ASCII characters in every other plugin's description.
Restore the file from main and change only the code-modernization entry.
Viewer (assets/topology-viewer.html):
- inline a minified d3 subset (hierarchy/pack, zoom, selection,
interpolateZoom, ease; ISC license) instead of loading from a CDN —
the page is now fully self-contained and works on air-gapped networks
- handle duplicate node ids (unique-suffix; edges bind to the first
occurrence) and store parent references directly, fixing
level-of-detail and selection corruption with messy generated data
- share one reveal rule between drawing, edge culling, and hit-testing
so edges no longer draw into collapsed containers
- pre-bucket edges by kind and keep a per-node adjacency map; the
hover/selection pass no longer scans every edge each frame
- cancel in-flight fly-to animations when a new one starts; clamp
fly-to zoom to the zoom extent; derive max zoom from the smallest
leaf so deep estates stay reachable
- render dead-end candidates (new deadEnds field) with a dashed
outline and a sidebar badge
- clicking a node during a flow walkthrough exits the walkthrough;
search results clear on selection and Escape; surrogate-safe label
truncation; clearer stats line; explicit empty-topology message
Commands:
- new /modernize-status: read-only progress report — artifact inventory
with timestamps, staleness flags, secrets-hygiene checks, next step
- map: deadEnds in the topology schema; datastore names must be logical
identifiers with credentials stripped from URLs/DSNs
- brief: read topology.json + .mmd files (not the interactive HTML);
staleness check against inputs; effort unit aligned to person-months
- transform: secret-safe characterization-test prompt; diff -y fallback
when delta is missing; credential-safe diff selection
- reimagine: target vision is everything after the first argument (was
silently truncated to one word); masking rules in spec/scaffold/
handoff prompts
- brief/transform/reimagine: human-approval gates phrased as explicit
stop-and-wait instead of 'enter plan mode'
- preflight: delta in the tool table; brief added to the verdict list
- README: preflight/status in the workflow; legacy/ deny list also
covers Write; plugin + marketplace descriptions updated
Fixes from an adversarial review of the new viewer:
- pin d3 to 7.9.0 and load it via dynamic import with an explicit
error panel when the CDN is unreachable (previously a blocked CDN
produced a silent dark page — a real concern for restricted networks)
- coerce ids/names/loc at intake: a single missing name or non-numeric
loc previously threw inside the render loop or propagated NaN through
the pack layout, blanking the canvas with no error
- normalize flows/steps/edges defensively (null entries, missing steps,
numeric ids vs string lookups)
- mirror the level-of-detail reveal rule in the hit test so clicks
can't select nodes that aren't drawn
- scope the Escape shortcut so clearing the search box doesn't reset
the viewport; set zoom clickDistance(4) so trackpad jitter doesn't
swallow selection clicks
- round canvas backing-store size (fractional devicePixelRatio caused
a reallocation every frame on 125%/150% display scaling)
- modernize-map: use braced ${CLAUDE_PLUGIN_ROOT} so substitution
actually happens, assert the injection marker exists in the template,
and correct the documented failure mode
modernize-map previously rendered the call graph and data lineage as
static Mermaid diagrams, which become unreadable once a node has ~10+
edges — exactly the shape of real legacy systems. It now builds an
interactive viewer from a shipped template (assets/topology-viewer.html):
a zoomable circle-pack of domains/modules sized by LOC, rendered to
canvas with level-of-detail reveal, dependency edges with per-kind
toggles, search with fly-to, a per-node detail sidebar, and a flow
walkthrough mode. Small domain-level .mmd exports remain for docs.
- topology.json now has a documented schema (hierarchy + edges + entry
points + observations + flows) consumed by the viewer
- map traces 2-4 business flows anchored to personas (claimant,
operator, auditor), each step in plain business language mapped to
the modules that implement it; the viewer plays them as numbered
paths
- brief gains a Business Walkthroughs section connecting each persona
flow to the phase that replaces it
- new modernize-preflight command: detects the stack, checks analysis
tooling, smoke-compiles a real source file with the legacy toolchain,
inventories missing copybooks/descriptors/binary-only artifacts, and
writes a per-command readiness verdict
- transform now verifies legacy + target toolchains before its plan
gate instead of failing at test time
- README: commands updated, optional-tooling section reframed as 'what
to give Claude'
assess only added SECRETS.local.md to analysis/.gitignore, leaving
*.local.patch uncovered until harden's own Step 0 ran. Both patterns are
now written by whichever command runs first.
A red-team pass found four ways credential values still reached
shareable artifacts after the initial redaction:
- the remediation patch: a diff removing a hardcoded secret carries the
raw value on its '-' lines by construction. harden now splits output:
non-credential hunks in the shareable security_remediation.patch,
credential hunks in a gitignored security_remediation.local.patch
with comment-only placeholders in the shareable file
- the other four agents had no secret-handling rules. legacy-analyst
(hardcoded-config evidence in tech-debt findings),
business-rules-extractor (credentials recorded as rule parameters),
test-engineer (legacy literals becoming committed test fixtures), and
architecture-critic (quoted code in notes files) now all mask values
and cite file:line; assess's tech-debt prompt and ASSESSMENT.md
masking now cover every section, not just Security Findings
- non-git projects: a .gitignore protects nothing under SVN/Mercurial.
Both commands now refuse --show-secrets without git and write the
quarantine file to ~/.modernize/<system>/ outside the project tree
- the patch-apply instruction was wrong in both documented layouts
(symlinked legacy/ broke relative paths). Patches are now written
with project-root-relative paths and applied from the project root
Also: --show-secrets is now position-independent in both commands, and
the README documents the full model.
Legacy systems often contain live credentials, and assessment/findings
files get committed and shared. Previously the security-auditor agent
reported hardcoded secrets verbatim into ASSESSMENT.md and
SECURITY_FINDINGS.md.
- security-auditor: mandatory secret-handling rules — mask all credential
values (file:line + 2-4 char preview), redact secrets from echoed tool
output, recommend rotation for anything that looks live
- assess/harden: gitignore-verified SECRETS.local.md quarantine file for
the per-credential inventory; findings files get masked entries and a
pointer only
- new --show-secrets flag opts into raw values in the quarantine file
(and only there)
- README: document the behavior and advise users of earlier versions to
check for already-committed findings and rotate
Refreshes the marketplace listing description for the AWS Startup Advisor
plugin at the maintainer's request.
Co-authored-by: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Adds an additional marketplace entry named `vanta` pointing to the same
source as the existing `vanta-mcp-plugin` entry (VantaInc/vanta-mcp-plugin
at the pinned SHA `345d86b5`). No code change — same upstream the existing
entry already uses; this exposes the plugin under the developer's canonical
plugin name (`vanta`, per the repo's plugin.json) alongside the existing slug.
Co-authored-by: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
@@ -7,7 +7,7 @@ A structured workflow and set of specialist agents for modernizing legacy codeba
Legacy modernization fails most often not because the target technology is wrong, but because teams skip steps: they transform code before understanding it, reimagine architecture before extracting business rules, or ship without a harness that would catch behavior drift. This plugin enforces a sequence:
The discovery commands (`assess`, `map`, `extract-rules`) build artifacts under `analysis/<system>/`. The `brief` command synthesizes them into an approval gate. The build commands (`reimagine`, `transform`) write new code under `modernized/`. The `harden` command audits the legacy system and produces a reviewable remediation patch. Each step has a dedicated slash command, and specialist agents (legacy analyst, business rules extractor, architecture critic, security auditor, test engineer) are invoked from within those commands — or directly — to keep the work honest.
@@ -20,25 +20,40 @@ Commands take a `<system-dir>` argument and assume the system being modernized l
`/modernize-assess` works best with [`scc`](https://github.com/boyter/scc) (LOC + complexity + COCOMO) or [`cloc`](https://github.com/AlDanial/cloc), and falls back to `find`/`wc` if neither is installed. Portfolio mode also benefits from [`lizard`](https://github.com/terryyin/lizard) (cyclomatic complexity). The commands degrade gracefully without them, but the metrics will be coarser.
The commands degrade gracefully, but each of these makes the output meaningfully better — run `/modernize-preflight <system-dir>` to check all of them at once and get a readiness report:
- **Analysis tools**: [`scc`](https://github.com/boyter/scc) (LOC + complexity + COCOMO) or [`cloc`](https://github.com/AlDanial/cloc); [`lizard`](https://github.com/terryyin/lizard) for portfolio mode. Without them, metrics fall back to `find`/`wc` and get coarser.
- **A working build toolchain** for the legacy stack (e.g. GnuCOBOL for COBOL) — required before `/modernize-transform` can prove behavioral equivalence, and verified by preflight with a real smoke compile against your code.
- **The whole system in the tree**: deployment descriptors (JCL, CICS definitions, route configs), copybooks/includes, and DDL/schemas. Entry-point detection and data lineage in `/modernize-map` are guesswork without them.
- **Production telemetry** (optional): an observability MCP server or batch job logs enable the runtime overlay in `/modernize-assess` and timing annotations on critical paths.
## Secret handling
Legacy systems routinely contain live credentials, and assessment artifacts get committed and shared. **Every agent in this plugin masks credential values** — findings, rule-card parameters, architecture notes, and test fixtures cite `file:line` with a masked preview (`AKIA****`), never the value. When credentials are found, a per-credential inventory (type, location, blast radius, rotation recommendation) is written to `analysis/<system>/SECRETS.local.md`, which the commands gitignore before writing; on non-git projects the quarantine file goes to `~/.modernize/<system>/` instead. `/modernize-harden` splits its remediation diff so credential-removal hunks (which necessarily contain the raw value) land in a gitignored `security_remediation.local.patch`, never the shareable patch. Pass `--show-secrets` to include raw values in the quarantine file (and only there). If you ran an earlier version of this plugin on a real system, check whether `analysis/` artifacts containing credentials were committed or shared, and rotate anything that was.
## Commands
The commands are designed to be run in order, but each produces a standalone artifact so you can stop, review, and resume.
Environment readiness check, meant to run first: detects the legacy stack, checks analysis tooling, **smoke-compiles a real source file** with the legacy toolchain (the errors this surfaces — missing copybooks, wrong dialect flags — are the ones that otherwise appear mid-transform), inventories missing includes / deployment descriptors / binary-only artifacts, and probes for telemetry. Produces `analysis/<system>/PREFLIGHT.md` with a per-command Ready / Ready-with-gaps / Not-ready verdict.
### `/modernize-assess <system-dir>` — or — `/modernize-assess --portfolio <parent-dir>`
Inventory the legacy codebase: languages, line counts, complexity, build system, integrations, technical debt, security posture, documentation gaps, and a COCOMO-derived effort estimate. Produces `analysis/<system>/ASSESSMENT.md` and `analysis/<system>/ARCHITECTURE.mmd`. Spawns `legacy-analyst` (×2) and `security-auditor` in parallel for deep reads. With `--portfolio`, sweeps every subdirectory of a parent directory and writes a sequencing heat-map to `analysis/portfolio.html`.
### `/modernize-map <system-dir>`
Build a dependency and topology map of the **legacy** system: program/module call graph, data lineage (programs ↔ data stores), entry points, dead-end candidates, and one traced critical-path business flow. Writes a re-runnable extraction script and produces `analysis/<system>/topology.json` (machine-readable), `analysis/<system>/TOPOLOGY.html` (rendered Mermaid + architect observations), and standalone `call-graph.mmd`, `data-lineage.mmd`, and `critical-path.mmd`.

Build a dependency and topology map of the **legacy** system: program/module call graph, data lineage (programs ↔ data stores), entry points, dead-end candidates, and 2–4 traced business flows each anchored to a persona (the claimant, the operator, the auditor — not the maintainer). Writes a re-runnable extraction script and produces `analysis/<system>/topology.json` plus `analysis/<system>/TOPOLOGY.html` — an **interactive zoomable map** (circle-pack of domains/modules sized by LOC, dependency edges with per-kind toggles, search, click-for-details sidebar, and a walkthrough mode that plays each persona flow as a numbered path with a plain-language narrative). Built from a template shipped with the plugin, so it works on systems far too dense for a static diagram. Small domain-level `call-graph.mmd`, `data-lineage.mmd`, and `critical-path.mmd` are still exported for docs and PRs.
Mine the business rules embedded in the legacy code — calculations, validations, eligibility, state transitions, policies — into Given/When/Then "Rule Cards" with `file:line` citations and confidence ratings. Spawns three `business-rules-extractor` agents in parallel (calculations, validations, lifecycle). Produces `analysis/<system>/BUSINESS_RULES.md` and `analysis/<system>/DATA_OBJECTS.md`.
Synthesize the discovery artifacts into a phased **Modernization Brief** — the single document a steering committee approves and engineering executes: target architecture, strangler-fig phase plan with entry/exit criteria, behavior contract, validation strategy, open questions, and an approval block. Reads `ASSESSMENT.md`, `TOPOLOGY.html`, and `BUSINESS_RULES.md` and **stops if any are missing** — run the discovery commands first. Produces `analysis/<system>/MODERNIZATION_BRIEF.md` and enters plan mode as a human-in-the-loop gate.
Synthesize the discovery artifacts into a phased **Modernization Brief** — the single document a steering committee approves and engineering executes: target architecture, strangler-fig phase plan with entry/exit criteria, persona-based business walkthroughs (the section non-technical approvers actually read), behavior contract, validation strategy, open questions, and an approval block. Reads `ASSESSMENT.md`, `TOPOLOGY.html`, and `BUSINESS_RULES.md` and **stops if any are missing** — run the discovery commands first. Produces `analysis/<system>/MODERNIZATION_BRIEF.md` and enters plan mode as a human-in-the-loop gate.
Greenfield rebuild from extracted intent rather than a structural port. Mines a spec (`analysis/<system>/AI_NATIVE_SPEC.md`), designs a target architecture and has it adversarially reviewed (`analysis/<system>/REIMAGINED_ARCHITECTURE.md`), then **scaffolds services with executable acceptance tests** under `modernized/<system>-reimagined/` and writes a `CLAUDE.md` knowledge handoff for the new system. Two human-in-the-loop checkpoints. Spawns `business-rules-extractor`, `legacy-analyst` (×2), `architecture-critic`, and general-purpose scaffolding agents.
@@ -46,6 +61,9 @@ Greenfield rebuild from extracted intent rather than a structural port. Mines a
Surgical, single-module strangler-fig rewrite. Plans first (HITL gate), then writes characterization tests via `test-engineer`, then an idiomatic target implementation under `modernized/<system>/<module>/`, proves equivalence by running the tests, and produces `TRANSFORMATION_NOTES.md` mapping legacy → modern with deliberate deviations called out. Reviewed by `architecture-critic`.
### `/modernize-status <system-dir>`
Read-only progress report: artifact inventory with timestamps per workflow stage, staleness flags (e.g. a brief older than the assessment it was built from), secrets-hygiene checks (quarantine file gitignored and never committed), and the single most useful next command. Run it anytime you come back to a modernization after a break.
### `/modernize-harden <system-dir>`
Security hardening pass on the **legacy** system: OWASP/CWE scan, dependency CVEs, secrets, injection. Spawns `security-auditor`. Produces `analysis/<system>/SECURITY_FINDINGS.md` ranked Critical / High / Medium / Low and a reviewed `analysis/<system>/security_remediation.patch` with minimal fixes for the Critical/High findings. The patch is reviewed by a second `security-auditor` pass before you see it. **Never edits `legacy/`** — you review and apply the patch yourself when ready, then re-run to verify. Useful as a pre-modernization step when the legacy system will keep running in production during the migration.
@@ -81,17 +99,21 @@ This plugin ships commands and agents, but modernization projects benefit from a
"Edit(modernized/**)"
],
"deny":[
"Edit(legacy/**)"
"Edit(legacy/**)",
"Write(legacy/**)"
]
}
}
```
Adjust `legacy/` and `modernized/` to match your actual layout. The key invariants: `Edit` under `legacy/`is denied, and writes are scoped to `analysis/` (for documents) and `modernized/` (for the new code). Every command in this plugin respects this — `/modernize-harden` writes a patch to `analysis/` rather than editing `legacy/` in place.
Adjust `legacy/` and `modernized/` to match your actual layout. The key invariants: `Edit`/`Write` under `legacy/`are denied, and writes are scoped to `analysis/` (for documents) and `modernized/` (for the new code). Note this guards the file tools — shell commands that mutate files (`sed -i`, `git apply`) still go through the normal Bash permission prompt, so review those prompts with the same invariant in mind. Every command in this plugin respects this — `/modernize-harden` writes a patch to `analysis/` rather than editing `legacy/` in place.
## Typical Workflow
```bash
# 0. Check the environment is ready (tools, toolchain, source completeness)
/modernize-preflight billing
# 1. Inventory the legacy system (or sweep a portfolio of them)
/modernize-assess billing
@@ -112,6 +134,9 @@ Adjust `legacy/` and `modernized/` to match your actual layout. The key invarian
# 6. Security-harden the legacy system that's still in production
(Fall back to `diff -y --width=160` if `delta` isn't installed.) Never
pick a credential-bearing line range for this diff, and mask any
credential-like literal quoted in TRANSFORMATION_NOTES.md — the notes
live in `modernized/` and get committed.
## Step 5 — Architecture review
Reference in New Issue
Block a user
Blocking a user prevents them from interacting with repositories, such as opening or commenting on pull requests or issues. Learn more about blocking a user.