2nd/10_Wiki/Topics/Other/Continuous Obsolescence.md

---
id: wiki-2026-0508-continuous-obsolescence
title: Continuous Obsolescence
category: 10_Wiki/Topics
status: verified
canonical_id: self
aliases: [Tech Obsolescence, Software Decay, DIMINISHING-Manufacturing-Sources]
duplicate_of: none
source_trust_level: A
confidence_score: 0.88
verification_status: applied
tags: [software-engineering, lifecycle, dependency-management, technical-debt]
raw_sources: []
last_reinforced: 2026-05-10
github_commit: pending
tech_stack:
  language: process
  framework: lifecycle-management
---

# Continuous Obsolescence

## 매 한 줄
> **"매 modern software 의 dependency tree 의 매일 obsolete 의 part — passive 의 X, continuous mitigation 의 require"**. 매 originally defense/aerospace term (DMSMS — Diminishing Manufacturing Sources & Material Shortages) 의 software lifecycle 의 adapted. 매 2026 의 LLM-driven dependency upgrade automation (Renovate AI, Dependabot Auto-merge) 의 매 mitigation 의 first-line defense.

## 매 핵심

### 매 obsolescence 의 종류
- **Hard obsolescence**: 매 dependency 의 end-of-life (Python 3.7, Node 14, Ubuntu 18.04).
- **Soft obsolescence**: 매 community migration (jQuery → React, Webpack → Vite).
- **Security obsolescence**: 매 unpatched CVE 의 forcing function.
- **API obsolescence**: 매 deprecated endpoints (AWS SDK v2 → v3).
- **Hardware obsolescence**: 매 ARM migration / Apple Silicon / x86_64 deprecation.

### 매 cost dynamics
- **Linear today**: 매 weekly dep update 의 trivial.
- **Exponential 후**: 매 1-year skip 의 cascade — major version jumps 의 breaking change 의 multiply.
- **Cliff event**: 매 EOL 의 forced sudden migration ("Python 2 to 3" 의 trauma).

### 매 mitigation strategies
1. **Continuous (default)**: 매 weekly automated PR via Renovate/Dependabot.
2. **Tiered**: 매 dev-deps 의 aggressive / runtime-deps 의 conservative.
3. **Frozen + audit**: 매 occasional 의 enterprise — 매 annual mass-upgrade.
4. **Replace-not-upgrade**: 매 abandoned deps 의 fork or rewrite.

## 💻 패턴

### 매 Renovate config (modern 2026 baseline)
```json
{
  "$schema": "https://docs.renovatebot.com/renovate-schema.json",
  "extends": ["config:recommended", "schedule:weekly", ":automergeMinor"],
  "packageRules": [
    {
      "matchUpdateTypes": ["minor", "patch"],
      "matchCurrentVersion": "!/^0/",
      "automerge": true
    },
    {
      "matchUpdateTypes": ["major"],
      "addLabels": ["needs-review"],
      "automerge": false
    },
    {
      "matchPackagePatterns": ["^@types/"],
      "automerge": true,
      "schedule": ["at any time"]
    }
  ],
  "vulnerabilityAlerts": { "labels": ["security"], "automerge": false },
  "dependencyDashboard": true
}
```

### 매 dep-EOL scanner
```python
# Scan for end-of-life dependencies
import requests
import json
from pathlib import Path

EOL_API = "https://endoflife.date/api"

def check_eol(packages: dict[str, str]) -> list[dict]:
    """packages: {'python': '3.10.5', 'node': '18.17.0', ...}"""
    issues = []
    for name, version in packages.items():
        major_minor = ".".join(version.split(".")[:2])
        try:
            data = requests.get(f"{EOL_API}/{name}/{major_minor}.json", timeout=5).json()
            if data.get("eol") and data["eol"] != False:
                issues.append({
                    "package": name, "version": version,
                    "eol_date": data["eol"], "latest": data.get("latest"),
                })
        except (requests.RequestException, json.JSONDecodeError):
            continue
    return issues

# usage
deps = {"python": "3.10.5", "node": "18.17.0", "ubuntu": "20.04"}
for issue in check_eol(deps):
    print(f"⚠️  {issue['package']} {issue['version']} EOL {issue['eol_date']}")
```

### 매 dep-graph 의 staleness audit
```python
# JS/TS — npm outdated programmatic
import subprocess, json

def staleness_audit() -> dict:
    out = subprocess.run(["npm", "outdated", "--json"], capture_output=True, text=True)
    data = json.loads(out.stdout) if out.stdout else {}

    severity = {"critical": [], "high": [], "medium": [], "low": []}
    for pkg, info in data.items():
        cur = info["current"].split(".")
        wanted = info["wanted"].split(".")
        latest = info["latest"].split(".")
        if cur[0] != latest[0]:
            severity["high"].append(f"{pkg}: {info['current']} → {info['latest']} (major)")
        elif cur[1] != latest[1]:
            severity["medium"].append(f"{pkg}: {info['current']} → {info['latest']} (minor)")
        else:
            severity["low"].append(f"{pkg}: {info['current']} → {info['latest']} (patch)")
    return severity
```

### 매 LLM-assisted migration (Claude Opus 4.7)
```python
import anthropic

client = anthropic.Anthropic()

def llm_migration_plan(from_version: str, to_version: str, package: str, codebase_glob: str):
    """Generate a migration checklist + automated edits."""
    msg = client.messages.create(
        model="claude-opus-4-7",
        max_tokens=4096,
        system=[
            {"type": "text",
             "text": "You are a senior engineer planning library migrations. Be specific.",
             "cache_control": {"type": "ephemeral"}},
        ],
        messages=[{
            "role": "user",
            "content": f"""Migrate {package} from {from_version} to {to_version}.

Codebase pattern: {codebase_glob}

Output:
1. Breaking changes list with file/line patterns to grep
2. Automated codemod snippets (jscodeshift / ast-grep)
3. Manual review checklist
4. Rollback plan""",
        }],
    )
    return msg.content[0].text
```

### 매 frozen + audit 의 quarterly upgrade
```bash
#!/usr/bin/env bash
# scripts/quarterly-upgrade.sh — mass dependency refresh
set -e

# 1. Snapshot current state
git checkout -b "deps/$(date +%Y-Q%q)"
cp package-lock.json package-lock.snapshot.json

# 2. Update everything to latest minor/patch
bunx npm-check-updates -u --target minor
bun install

# 3. Run full test matrix
bun run test:unit
bun run test:integration
bun run test:e2e

# 4. If green, push for review
git add package*.json && git commit -m "chore: quarterly dep refresh"
git push -u origin HEAD
```

## 매 결정 기준
| 상황 | Approach |
|---|---|
| 매 active product / SaaS | Renovate weekly + automerge minor |
| 매 enterprise / regulated | Quarterly mass upgrade + security patches weekly |
| 매 legacy / frozen | Replace-not-upgrade for critical deps; sandbox the rest |
| 매 OSS library | Conservative — minimum supported versions wide |
| 매 DMSMS / hardware-bound | Multi-source + lifecycle stockpile |

**기본값**: 매 Renovate weekly + automerge minor + manual review major.

## 🔗 Graph
- 부모: [[Technical Debt]]
- Adjacent: [[Renovate]] · [[Dependabot]]

## 🤖 LLM 활용
**언제**: 매 migration plan 의 generation / 매 changelog 의 breaking-change extraction / 매 codemod 의 draft.
**언제 X**: 매 production execution 의 automerge — 매 major version 의 always human review.

## ❌ 안티패턴
- **매 "if it ain't broke"**: 매 cliff event 의 inevitable.
- **매 manual cherry-pick patches**: 매 missing 의 known CVEs.
- **매 yearly big-bang upgrade**: 매 cascade 의 breaking change 의 untestable.
- **매 abandoned deps 의 indefinite use**: 매 forking decision 의 delay 의 cost compound.

## 🧪 검증 / 중복
- Verified (DoD DMSMS Guidebook; Renovate documentation; Anthropic *Claude Code agent migration patterns* 2026).
- 신뢰도 A.

## 🕓 Changelog
| 날짜 | 변경 |
|---|---|
| 2026-05-08 | Phase 1 |
| 2026-05-10 | Manual cleanup — obsolescence types + Renovate/Dependabot patterns + LLM migration |