Legacy Project Modernization

Incremental catch-up, not big-bang migration.

Projects months/years behind

The Challenge

18 months behind. Where do you even start?

The project runs Express 4, React 17, and 94 outdated packages. There are 12 known CVEs. Dependabot has been disabled because it opened 40 PRs that all failed CI.

A manual migration means reading changelogs for 8 major version bumps, applying code changes across hundreds of files, and hoping nothing breaks silently. That's a 3-week project, minimum.

Most teams keep pushing it off. The gap widens. The CVEs accumulate. The risk grows — until it becomes a crisis.

npm-outdated.log
Package              Current   Latest    Status
──────────────────────────────────────────────────
express                4.18.2    5.0.1    MAJOR ⚠
react                 17.0.2   19.1.0    MAJOR ⚠
react-dom             17.0.2   19.1.0    MAJOR ⚠
react-router-dom       5.3.4    7.1.0    MAJOR ⚠
eslint                 8.56.0    9.8.0    MAJOR ⚠
webpack                4.46.0    5.97.0   MAJOR ⚠
axios                  0.21.4    1.7.9    MAJOR ⚠
typescript             4.9.5    5.7.3     MAJOR ⚠
──────────────────────────────────────────────────
Outdated: 94 | Major: 8 | Critical CVEs: 12
Estimated manual effort: 120+ hours

How Ovvoc Helps

Incremental catch-up, not big-bang migration

Ovvoc doesn't try to update everything at once. It prioritizes security patches first, then works through minor updates, then tackles major version bumps in dependency-graph order.

Each update is a separate, tested PR. Express 4→5 gets its own PR with 8 AST transforms applied. React 17→19 gets its own PR. You merge independently, roll back independently.

What used to be a 3-week all-hands project becomes a week of reviewing and merging verified PRs at your own pace.

Manual approach (6 weeks, high risk)
  Week 1: Read 8 migration guides
  Week 2: Create mega-branch
  Week 3: Apply code changes
  Week 4: Fix cascading breakage
  Week 5: Stabilize tests
  Week 6: Code review + merge
  ─────────────────────────────────
  Risk: ONE broken merge = rollback all
Ovvoc approach (< 1 week, low risk)
  Day 1: CVE patches (12 PRs)
  Day 2: Minor updates (40 PRs)
  Day 3: Express 4→5 (1 PR, verified)
  Day 4: React 17→19 (1 PR, verified)
  Day 5: Remaining majors (6 PRs)
  ─────────────────────────────────
+ Risk: Each PR independent & tested

Key Benefits

From years behind to fully current

Intelligent Prioritization

Security CVEs first, then minor patches, then major upgrades in dependency-graph order. No manual triage.

Incremental, Not Big-Bang

Each update is a separate PR. Merge or rollback individually. No single massive branch that blocks everything.

120 Hours to 30 Minutes

3 weeks of manual migration work becomes a week of auto-generated, verified PRs to review at your own pace.

Failure Reports, Not Surprises

When a transform doesn't pass tests, you get a detailed report explaining what broke and why — not a broken build.

Workflow

How legacy projects get current

1

Connect and scan

Install the GitHub App. Ovvoc scans package.json and lockfile, builds a full dependency graph, and identifies the upgrade path.

2

Priority queue builds

CVEs patched first. Then minor/patch updates in batches. Then major upgrades with AST transforms — all in dependency-graph order.

3

Merge at your pace

PRs arrive in priority order. Each one is independently tested. Merge when ready — your project is current within days.

Ready to automate your dependency updates?

Start with one repo. See verified PRs instead of broken builds.

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