Хуучин кодоо яах вэ?

Одоо хүртэл ажиллаж байгаа чухал системүүдээ хэрхэн орчин үеийн болгох эсвэл хэзээ халах вэ?

Fire slowly by moving things to new services — Strangler fig pattern; extract to new services; incremental migration.

Strangler fig pattern — Replace legacy in slices by routing traffic to new services over time.
Extract to new services — When and how to move bounded contexts out of the monolith.
Incremental migration without big bang — Rollout and feature flags; coexistence of old and new.

Start upgrading within itself — In-place refactoring; modernize inside the monolith first.

In-place refactoring — Improve structure, tests, and dependencies without moving code out.
Modernize dependencies and runtime — Upgrade frameworks, language version, and libraries safely.
Modularize before extracting — Clear boundaries inside the monolith before splitting.

When to rewrite, risk, and testing — Rewrite vs. refactor; risk and rollout; testing legacy before touching.

When to rewrite vs. refactor — Cost and risk of full rewrite; when incremental is better.
Risk and rollout strategy — Canary, feature flags, rollback; not breaking production.
Testing the legacy before touching it — Characterization tests, safety net, and regression coverage.