Infer the physical architecture proposal (runtime, deployment target, data stores, caches, queues, search, observability, auth infrastructure, scaling strategy) from scan-index.json during /codify, naming specific products (Postgres 15, Redis 7, Kafka, etc.) — never categories. Every slot is grounded in concrete manifest / Dockerfile / infra / CI evidence and tagged source_type=inferred_from_code. Used exclusively by tech-architect in the /codify play.
Infer the physical architecture proposal (runtime, deployment target, data stores, caches, queues, search, observability, auth infrastructure, scaling strategy) from scan-index.json during /codify, naming specific products (Postgres 15, Redis 7, Kafka, etc.) — never categories. Every slot is grounded in concrete manifest / Dockerfile / infra / CI evidence and tagged source_type=inferred_from_code. Used exclusively by tech-architect in the /codify play.
version
0.1.0
user-invocable
false
model
sonnet
allowed-tools
Read, Write, Grep, Glob
deprecated
true
deprecated_note
#434 ProductOS realignment — superseded by the command model; retained for Phase E reference, not installed
infer-physical-architecture-from-code
Called by tech-architect during /codify, immediately after infer-logical-architecture-from-code. Produces architecture/physical-architecture.yaml at {stm_base}/{issue}/evidence/codify/proposals/architecture/physical-architecture.yaml.
Purpose
During /codify (brownfield bootstrap), the physical-architecture artifact that /arch normally derives from locked specs and grounded_tools pins must be reverse-engineered from the running codebase. This skill consumes scan-index.json (produced by scan-codebase) plus the sibling logical-architecture.yaml proposal and emits a physical-architecture proposal grounded entirely in what the code already reveals.
Unlike logical-architecture.yaml, this is THE artifact that names specific products. Every slot MUST resolve to a named product with a version when evidence allows (e.g. "PostgreSQL 15", "Redis 7", "Apache Kafka 3.6"). Slots where evidence is absent are marked unknown_with_gap and surfaced as a knowledge_gaps entry — never filled with category words like "a relational database" or "some cache".
Signals this skill extracts from scan-index:
runtime — per manifest, framework dep + version source:
jvm + spring-boot-starter* → JVM + Spring Boot (version from parent pom / gradle plugin)
dotnet + Microsoft.AspNetCore.App → .NET (TargetFramework in csproj)
elixir + phoenix → Elixir + Phoenix (version from mix.exs)
container runtime — config_files.docker: Dockerfile FROM base image (e.g. node:20-alpine, python:3.12-slim, golang:1.22) → container base + version; multi-stage FROM ... AS builder → build stage signal; docker-compose.yml services list → often the clearest signal for data/cache/queue product versions.
scaling strategy hints: HorizontalPodAutoscaler in k8s manifests, autoscale/minInstances/maxInstances in app.yaml, [services.concurrency] in fly.toml, provisionedConcurrency in serverless.yml → autoscale policy per tier; pm2 ecosystem, gunicorn --workers, uvicorn --workers, puma workers/threads → concurrency model; bullmq / celery worker definitions → queue-depth-driven scaling; Vercel / Netlify / Cloudflare Workers → "managed edge autoscaling".
Any signal unavailable in scan-index for a given slot is surfaced in knowledge_gaps[] (slot name + what evidence would be needed) and the slot is written as unknown_with_gap — never guessed, never filled with a category word.
Input
Receive from tech-architect via JSON contract.
scan_index_path (path, required) — scan-index.json produced by scan-codebase.
stm_base (path, required) — STM root resolved from .garura/core/config.yamlstm.base-path.
issue (str, required) — issue number driving /codify.
decision_manifest_path (path, required) — decision-manifest-infer-physical-architecture-from-code.yaml alongside the artifact.
related_proposal_paths (map, required) — MUST contain logical_architecture pointing to the sibling architecture/logical-architecture.yaml proposal. bounded_contexts and components come from there; this skill maps them onto physical runtimes and tiers.
resolution_trace_path (path, required) — where resolution-trace.yaml is written.
Process
Validate inputs. Confirm scan_index_path exists and parses as JSON. Confirm logical-architecture.yaml at related_proposal_paths.logical_architecture exists and parses. If either is missing or malformed → structured failure scan_index_missing or missing_related_proposal.
Check scan status. Read scan_status. If budget_exhausted, proceed but mark every inferred slot confidence: low in the manifest and record a top-level warning in the artifact meta (scan_status_warning: "scan truncated — signals may be partial").
Execute LTM Resolution Protocol R3 per core/components/memory/standards/rules/resolution.md. Query the core KB arch/platforms/, arch/data/, arch/operations/ domains for candidate catalogues. Write the trace to resolution_trace_path. The KB is a reference for known-product families; it does NOT override scan-index evidence — when the codebase plainly uses PostgreSQL, that is the answer regardless of what the KB recommends.
Map bounded contexts to deployment targets. For each bounded_context in logical-architecture, determine its deployment target from config_files.ci, config_files.infra, config_files.deploy, and the Dockerfile / docker-compose.yml structure. Record the mapping in deployment.topology[].logical_components.
Detect data stores. Walk manifest deps against the data-store dep→product table above. De-duplicate by product family. For each detected product, capture version from (a) compose-service image tag, (b) Dockerfile FROM base image, (c) manifest dep pin (e.g. "pg": "^8.11.0" fixes Postgres driver, not server version — in that case, mark server version as unknown_with_gap).
Detect caches, queues, search. Same pattern as data stores, against their respective dep→product tables.
Detect observability stack. Walk manifest deps against the observability table. Split findings into the four sub-slots: logging, metrics, tracing, errors. Absence of any sub-slot signal → unknown_with_gap for that sub-slot.
Detect auth infrastructure. Walk manifest deps against the auth table. Record the primary auth product in auth_infrastructure.choice; record JWT / MFA libraries under auth_infrastructure.token_library and auth_infrastructure.mfa_library when present.
Detect scaling strategy. Inspect infra/deploy configs for autoscale blocks, worker pool configs, and edge-platform signals per the scaling-strategy table. For each runtime tier in deployment.topology, record scaling_strategy.{tier_id}. Tiers with no scaling signal → unknown_with_gap.
Populate knowledge_gaps. For every slot marked unknown_with_gap, emit an entry {slot, evidence_needed, suggested_question} so the orchestrator's checkpoint can ask the user.
Compose the artifact YAML. Write meta block first, then physical_architecture body. Meta lists every scan-index evidence path consulted across all slots (deduplicated).
Write decision manifest. One entry per inferred slot with tier, grounding_source (scan-index:<path> or ltm:<file>), recommendation (the specific product + version or unknown_with_gap), alternatives_considered (other products the scan could have indicated), and confidence. For unknown_with_gap entries, alternatives_considered MUST list the plausible products that would have been picked had evidence been present.
Output
Primary artifact at output_path:
meta:source_type:"inferred_from_code"evidence:-"scan-index.json#/manifests/0/dependencies"-"scan-index.json#/config_files/docker"-"scan-index.json#/config_files/infra"-"scan-index.json#/config_files/deploy"-"scan-index.json#/config_files/ci"confidence:"high"|"medium"|"low"learning_category:"arch"sub_category:"platforms"tier:1scan_status_warning:null# or message string when scan_status == budget_exhaustedphysical_architecture:runtime:choice:"Node.js 20"# specific product + versionevidence: ["scan-index.json#/manifests/0/engines/node", "scan-index.json#/config_files/docker/Dockerfile"]
confidence:"high"deployment:provider:"AWS"# AWS | GCP | Azure | Vercel | Fly.io | Heroku | Render | Railway | Netlify | Cloudflare | self-hosted-k8s | unknown_with_gaptopology:-tier_id:"tier-api"host:"AWS ECS Fargate"logical_components: ["comp-api-gateway", "comp-auth-service"]
evidence: ["scan-index.json#/config_files/infra/terraform/ecs.tf"]
-tier_id:"tier-web"host:"Vercel"logical_components: ["comp-web-frontend"]
evidence: ["scan-index.json#/config_files/deploy/vercel.json"]
data_stores:-type:"relational"product:"PostgreSQL"version:"15"# from compose image tag or Dockerfileevidence: ["scan-index.json#/manifests/0/dependencies/pg", "scan-index.json#/config_files/docker/docker-compose.yml"]
confidence:"high"# one entry per detected data product; unknown_with_gap allowedcaches:-product:"Redis"version:"7"evidence: ["scan-index.json#/manifests/0/dependencies/ioredis"]
confidence:"high"queues:-product:"Apache Kafka"version:"3.6"evidence: ["scan-index.json#/manifests/0/dependencies/kafkajs", "scan-index.json#/config_files/docker/docker-compose.yml"]
confidence:"high"search:-product:"OpenSearch"version:"2.x"evidence: ["scan-index.json#/manifests/0/dependencies/@opensearch-project/opensearch"]
confidence:"medium"observability:logging:choice:"Pino → Axiom"evidence: ["scan-index.json#/manifests/0/dependencies/pino", "scan-index.json#/manifests/0/dependencies/@axiomhq/js"]
confidence:"high"metrics:choice:"Prometheus client (prom-client)"evidence: ["scan-index.json#/manifests/0/dependencies/prom-client"]
confidence:"high"tracing:choice:"OpenTelemetry SDK"evidence: ["scan-index.json#/manifests/0/dependencies/@opentelemetry/sdk-node"]
confidence:"high"errors:choice:"Sentry"evidence: ["scan-index.json#/manifests/0/dependencies/@sentry/node"]
confidence:"high"auth_infrastructure:choice:"Auth0"token_library:"jsonwebtoken"mfa_library:"speakeasy"evidence: ["scan-index.json#/manifests/0/dependencies/@auth0/nextjs-auth0"]
confidence:"high"scaling_strategy:tier-api:approach:"Kubernetes HorizontalPodAutoscaler (CPU > 70% → 2..10 replicas)"evidence: ["scan-index.json#/config_files/infra/k8s/hpa.yaml"]
confidence:"high"tier-web:approach:"Vercel managed edge autoscaling"evidence: ["scan-index.json#/config_files/deploy/vercel.json"]
confidence:"high"tier-worker:approach:"unknown_with_gap"confidence:"low"knowledge_gaps:-slot:"scaling_strategy.tier-worker"evidence_needed:"worker concurrency config (pm2 ecosystem, gunicorn workers, or HPA for worker deployment)"suggested_question:"How are background workers scaled today — fixed replicas, queue-depth autoscale, or manual?"
Decision manifest at decision_manifest_path:
decisions:-slot:"runtime"tier:1grounding_source:"scan-index:manifests[0].engines.node"recommendation:"Node.js 20"alternatives_considered:-alt:"Node.js 18"why_not:"engines.node pins '>=20'"confidence:"high"-slot:"data_stores[0]"tier:1grounding_source:"scan-index:manifests[0].dependencies.pg + docker-compose.yml service 'db' image postgres:15"recommendation:"PostgreSQL 15"alternatives_considered:-alt:"PostgreSQL 16"why_not:"compose pins image tag 15, not 16"confidence:"high"# one entry per inferred slot (runtime, deployment.provider, each topology tier,# each data_store, each cache, each queue, each search entry, each observability sub-slot,# auth_infrastructure, each scaling_strategy tier). unknown_with_gap slots MUST also appear# here with alternatives_considered listing plausible products that would have been picked# had evidence been present.
Resolution trace at resolution_trace_path per resolution.md schema.
No product LTM writes. All output is under STM.
Failure Modes
missing_related_proposal — related_proposal_paths.logical_architecture does not exist or is not valid YAML; this skill cannot map contexts to runtimes without it.
scan_index_missing — scan_index_path does not exist or is not valid JSON.
scan_status_exhausted — scan-index has scan_status: budget_exhausted; skill proceeds but lowers confidence across all slots and records a meta-level warning.
insufficient_signal — very thin config surface (no Dockerfile, no infra configs, no deploy configs, minimal manifest deps). Emit the artifact with slots populated only where manifest-dep evidence exists; all other slots become unknown_with_gap with knowledge_gaps[] populated. Do NOT fabricate picks to avoid gaps — gaps are the correct output when evidence is absent.
ltm_resolution_failed — Resolution Protocol raised an error; skill halts and returns the trace path for triage.
output_parent_missing — output_path parent cannot be created; return structured failure.
Boundaries
Read-only against the codebase. The scan-index plus the sibling logical-architecture proposal are the sole inputs — this skill does NOT open source files directly.
NEVER use category terms. Every slot names a specific product (with a version when evidence allows) OR is unknown_with_gap. "A relational database", "some queue", "a cache layer" are validator-rejected strings.
NEVER invent a product name not indicated by scan-index evidence. If kafkajs is absent and no compose service names Kafka, the queues slot is unknown_with_gap — not "probably Kafka".
NEVER override a product the code plainly uses in favour of a KB recommendation. When Postgres is in the manifest and compose, the answer is Postgres regardless of what arch/data/relational.md recommends for greenfield.
Signals not listed in the Purpose section MUST NOT be used as evidence; add them to this skill's contract before relying on them.
No writes outside {stm_base}/{issue}/evidence/codify/proposals/architecture/ and the two companion files (decision manifest, resolution trace).
