diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index a581e16..0b7bd93 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -2,9 +2,9 @@ name: CI
 
 on:
   push:
-    branches: [ main, develop ]
+    branches: [ main, develop, 1.x ]
   pull_request:
-    branches: [ main, develop ]
+    branches: [ main, develop, 1.x ]
 
 jobs:
   verify:
diff --git a/CHANGELOG.md b/CHANGELOG.md
index a9af3d6..767da17 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -5,7 +5,13 @@ All notable changes to this project are documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.1.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
-## [Unreleased]
+## [1.0.0] - 2026-08-05
+
+The legacy-decorator line, promoted from 0.1.0 and now maintained in parallel with 2.x.
+Functionally identical to the previous unreleased state; only the version and the
+maintenance-line notice changed. See the 2.x branch for standard decorators and
+compile-time rule checking.
+
 
 ### Added
 
diff --git a/README.md b/README.md
index 189efbd..e1fd91e 100644
--- a/README.md
+++ b/README.md
@@ -1,5 +1,15 @@
 # Cereale
 
+> **This is the 1.x maintenance line**, which uses TypeScript's legacy
+> `experimentalDecorators`. It is feature-complete and supported for bug fixes.
+>
+> **New projects should use 2.x**, which moves to TC39 standard decorators and gains
+> compile-time checking of validation rules against field types — `@IsString() age: number`
+> becomes a compile error rather than a runtime surprise.
+>
+> Stay on 1.x if your toolchain transpiles with **oxc**, which does not yet implement the
+> standard decorator transform. `tsc` and esbuild both do, so most projects can move.
+
 Cereale is a lightweight TypeScript library that provides Spring-like decorators for JSON mapping and validation. Built with ZERO external dependencies, it simplifies the process of converting between plain JSON and class instances with full validation support.
 
 ## Features
diff --git a/package-lock.json b/package-lock.json
index 518e587..e5f3393 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -1,12 +1,12 @@
 {
   "name": "cereale",
-  "version": "0.1.0",
+  "version": "1.0.0",
   "lockfileVersion": 3,
   "requires": true,
   "packages": {
     "": {
       "name": "cereale",
-      "version": "0.1.0",
+      "version": "1.0.0",
       "license": "MIT",
       "devDependencies": {
         "@eslint/js": "^10.0.1",
diff --git a/package.json b/package.json
index 59010f3..05eeb9c 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "cereale",
-  "version": "0.1.0",
+  "version": "1.0.0",
   "description": "Spring-like decorators for JSON mapping and validation in TypeScript",
   "type": "module",
   "main": "./dist/cjs/index.js",