diff --git a/.buildconfig/fixup b/.buildconfig/fixup
new file mode 100755
index 0000000..a9233e3
--- /dev/null
+++ b/.buildconfig/fixup
@@ -0,0 +1,13 @@
+#!/bin/bash
+
+cat << EOF > ./lib/cjs/package.json
+{
+    "type": "commonjs"
+}
+EOF
+
+cat << EOF > ./lib/mjs/package.json
+{
+    "type": "module"
+}
+EOF
diff --git a/.buildconfig/tsconfig.cjs.json b/.buildconfig/tsconfig.cjs.json
new file mode 100644
index 0000000..de7a807
--- /dev/null
+++ b/.buildconfig/tsconfig.cjs.json
@@ -0,0 +1,12 @@
+{
+  "extends": "./tsconfig.json",
+  "compilerOptions": {
+    "module": "commonjs",
+    "outDir": "../lib/cjs",
+    "target": "es2015"
+  },
+  "include": [
+    "../src",
+    "../index.ts"
+  ]
+}
diff --git a/tsconfig.cli.json b/.buildconfig/tsconfig.cli.json
similarity index 70%
rename from tsconfig.cli.json
rename to .buildconfig/tsconfig.cli.json
index 8e7c89c..b48e8e0 100644
--- a/tsconfig.cli.json
+++ b/.buildconfig/tsconfig.cli.json
@@ -6,6 +6,10 @@
     "module": "CommonJS",
     "moduleResolution": "node",
     "esModuleInterop": true,
-    "outDir": "dist"
-  }
+    "outDir": "../lib/cli"
+  },
+  "include": [
+    "../src",
+    "../index.ts"
+  ]
 }
\ No newline at end of file
diff --git a/tsconfig.json b/.buildconfig/tsconfig.json
similarity index 69%
rename from tsconfig.json
rename to .buildconfig/tsconfig.json
index 51d6e1e..ad69226 100644
--- a/tsconfig.json
+++ b/.buildconfig/tsconfig.json
@@ -4,11 +4,14 @@
     "strict": true,
     "forceConsistentCasingInFileNames": true,
     "module": "commonjs",
-    "moduleResolution": "node",
-    "outDir": "lib"
+    "moduleResolution": "node"
   },
   "types": [
     "node",
     "jest"
+  ],
+  "include": [
+    "../src",
+    "../index.ts"
   ]
 }
diff --git a/.buildconfig/tsconfig.mjs.json b/.buildconfig/tsconfig.mjs.json
new file mode 100644
index 0000000..b35f09a
--- /dev/null
+++ b/.buildconfig/tsconfig.mjs.json
@@ -0,0 +1,12 @@
+{
+  "extends": "./tsconfig.json",
+  "compilerOptions": {
+    "module": "ESNext",
+    "outDir": "../lib/mjs",
+    "target": "ESNext"
+  },
+  "include": [
+    "../src",
+    "../index.ts"
+  ]
+}
diff --git a/.github/workflows/release.yml b/.github/workflows/release.yml
index 8937e2c..aef8f74 100644
--- a/.github/workflows/release.yml
+++ b/.github/workflows/release.yml
@@ -2,6 +2,8 @@ name: Release
 
 on:
   push:
+    branches:
+      - master
     tags:
       - 'v*'
 
@@ -21,6 +23,12 @@ jobs:
       - name: Install dependencies
         run: npm ci
 
+      - name: Type check
+        run: npm run type-check
+
+      - name: Test
+        run: npm test
+
       - name: Build library
         run: npm run build
 
@@ -42,9 +50,9 @@ jobs:
           draft: false
           prerelease: false
           files: |
-            bin/crumb-linux
-            bin/crumb-macos
-            bin/crumb-win.exe
+            bin/crumbjs-linux
+            bin/crumbjs-macos
+            bin/crumbjs-win.exe
         env:
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
 
diff --git a/.github/workflows/test-on-pr.yml b/.github/workflows/test-on-pr.yml
new file mode 100644
index 0000000..7dc00a7
--- /dev/null
+++ b/.github/workflows/test-on-pr.yml
@@ -0,0 +1,22 @@
+name: Run Tests on PR
+
+on:
+  pull_request:
+
+jobs:
+  test:
+    runs-on: ubuntu-latest
+
+    steps:
+      - uses: actions/checkout@v3
+
+      - name: Setup Node.js
+        uses: actions/setup-node@v3
+        with:
+          node-version: '18'
+
+      - name: Install dependencies
+        run: npm install
+
+      - name: Run tests
+        run: npm test
\ No newline at end of file
diff --git a/README.md b/README.md
index c7a21f2..0a2c54f 100644
--- a/README.md
+++ b/README.md
@@ -5,10 +5,8 @@ számos egyéb alapeszközt biztosít természetes mondatok generálásához.
 
 ## Telepítés
 
-A teljes projekt telepítése:
-
 ```bash
-npm install crumb
+npm install crumbjs
 ```
 
 ## Használat
@@ -18,7 +16,7 @@ npm install crumb
 A toldalékoláshoz használd a `suffix` metódust:
 
 ```javascript
-import {suffix} from 'crumb';
+import {suffix} from 'crumbjs';
 
 suffix.dative('kutya'); // "kutyának"
 ```
@@ -37,7 +35,7 @@ A csomag a következő toldalékokat támogatja:
 - `delative`: leható eset (-ról, -ről) - pl. `suffix.delative('tető')` → "tetőről"
 - `elative`: kiható eset (-ból, -ből) - pl. `suffix.elative('doboz')` → "dobozból"
 - `illative`: beható eset (-ba, -be) - pl. `suffix.illative('ház')` → "házba"
-- `insessive`: bentlakó eset (-ban, -ben) - pl. `suffix.insessive('kert')` → "kertben"
+- `inessive`: bentlakó eset (-ban, -ben) - pl. `suffix.inessive('kert')` → "kertben"
 - `sublative`: felható eset (-ra, -re) - pl. `suffix.sublative('asztal')` → "asztalra"
 - `superessive`: felülmaradó eset (-on, -en, -ön) - pl. `suffix.superessive('föld')` → "földön"
 - `terminative`: határvető eset (-ig) - pl. `suffix.terminative('sarok')` → "sarokig"
@@ -67,13 +65,36 @@ A csomag a következő toldalékokat támogatja:
 A csomag támogatja a melléknevek fokozását is a `grade` objektumon keresztül:
 
 ```javascript
-import {grade} from 'crumb';
+import {grade} from 'crumbjs';
 
 grade.comparative('szép'); // "szebb"
 grade.superlative('szép'); // "legszebb"
 grade.excessive('szép');   // "legeslegszebb"
 ```
 
+## Számok szöveggé alakítása
+
+```javascript
+import {getNumberWithWords} from 'crumbjs'
+
+getNumberWithWords('1625');       // "ezerhatszázhuszonöt"
+getNumberWithWords('-13.4');      // "mínusz tizenhárom egész négy tized"
+getNumberWithWords('48239845');   // "negyvennyolcmillió-kétszázharminckilencezer-nyolcszáznegyvenöt"
+```
+
+## Szótagolás
+
+```javascript
+import {getSyllables} from 'crumbjs'
+
+getSyllables('kivirágozhat');     // ["ki", "vi", "rá", "goz", "hat"]
+getSyllables('kellemetlenség');   // ["kel", "le", "met", "len", "ség"]
+
+// Nincs szótár, nem ismeri fel a szóhatárokat
+getSyllables('kerítésszaggató', {stopWords: ["kerítés"], formatted: true}); // ke-rí-tés-szag-ga-tó
+getSyllables('pánikroham', {formatted: true, hypenCharacter: '/'}); // pá/nik/ro/ham
+```
+
 ##### Speciális esetek és kivételek
 
 A csomag kezeli a magyar nyelv speciális eseteit és kivételeit, például:
@@ -86,13 +107,13 @@ A csomag kezeli a magyar nyelv speciális eseteit és kivételeit, például:
 ##### Példák
 
 ```javascript
-import {suffix, grade} from 'crumb';
+import {suffix, grade} from 'crumbjs';
 
 // Esetragok
 suffix.accusative('alma');     // "almát"
 suffix.dative('ház');          // "háznak"
 suffix.ablative('iskola');     // "iskolától"
-suffix.insessive('doboz');     // "dobozban"
+suffix.inessive('doboz');     // "dobozban"
 suffix.superessive('szék');    // "széken"
 
 // Többes szám
diff --git a/package.json b/package.json
index 3fbe184..bf75c82 100644
--- a/package.json
+++ b/package.json
@@ -1,18 +1,24 @@
 {
   "name": "crumbjs",
   "version": "1.0.0",
-  "main": "index.js",
+  "main": "lib/cjs/index.js",
+  "author": {
+    "name": "Péter Viola",
+    "email": "info@violapeter.hu",
+    "url": "https://violapeter.hu"
+  },
   "license": "MIT",
   "scripts": {
     "test": "jest",
-    "build": "tsc",
-    "build:cli": "tsc --project tsconfig.cli.json",
-    "start": "node dist/src/cli/index.js",
+    "build": "tsc -p .buildconfig/tsconfig.mjs.json && tsc -p .buildconfig/tsconfig.cjs.json && .buildconfig/fixup",
+    "build:cli": "tsc --project .buildconfig/tsconfig.cli.json",
+    "start": "node ./lib/cli/src/cli/index.js",
     "dev": "ts-node ./src/cli/index.ts",
-    "package": "pkg . --out-path=bin"
+    "package": "pkg . --out-path=bin",
+    "type-check": "tsc -p .buildconfig/tsconfig.json --noEmit"
   },
   "bin": {
-    "crumb": "dist/src/cli/index.js"
+    "crumb": "lib/cli/src/cli/index.js"
   },
   "devDependencies": {
     "@types/jest": "^29.5.14",
@@ -26,6 +32,20 @@
     "commander": "^13.1.0",
     "typescript": "^5.8.3"
   },
+  "module": "lib/mjs/index.js",
+  "exports": {
+    ".": {
+      "import": "./lib/mjs/index.js",
+      "require": "./lib/cjs/index.js"
+    }
+  },
+  "types": "./types.d.ts",
+  "files": [
+    "lib",
+    "src",
+    "index.ts",
+    "types.d.ts"
+  ],
   "pkg": {
     "targets": [
       "node18-linux-x64",
@@ -39,7 +59,7 @@
       "^.+\\.ts$": [
         "ts-jest",
         {
-          "tsconfig": "tsconfig.json"
+          "tsconfig": ".buildconfig/tsconfig.json"
         }
       ]
     },
@@ -55,5 +75,6 @@
     "singleQuote": true,
     "trailingComma": "all",
     "semi": false
-  }
+  },
+  "packageManager": "yarn@1.22.19+sha1.4ba7fc5c6e704fce2066ecbfb0b0d8976fe62447"
 }
diff --git a/src/suffix/__tests__/_smoke.spec.ts b/src/suffix/__tests__/_smoke.spec.ts
index a6ff81d..0681c81 100644
--- a/src/suffix/__tests__/_smoke.spec.ts
+++ b/src/suffix/__tests__/_smoke.spec.ts
@@ -15,7 +15,7 @@ const testData: Array<[string, string, string, SuffixerMethod]> = [
   ['essiveFormal', 'kalapács', 'kalapácsként', suffix.essiveFormal],
   ['essiveModal', 'kalapács', 'kalapácsul', suffix.essiveModal],
   ['illative', 'kalapács', 'kalapácsba', suffix.illative],
-  ['insessive', 'kalapács', 'kalapácsban', suffix.insessive],
+  ['inessive', 'kalapács', 'kalapácsban', suffix.inessive],
   [
     'instrumentalComitative',
     'kalapács',
diff --git a/src/suffix/index.ts b/src/suffix/index.ts
index e337a83..d6331fe 100644
--- a/src/suffix/index.ts
+++ b/src/suffix/index.ts
@@ -67,7 +67,7 @@ export const suffix = {
       high: 'be',
     }),
   ),
-  insessive: createSuffixer(
+  inessive: createSuffixer(
     createSuffixSelector({
       low: 'ban',
       high: 'ben',
diff --git a/types.d.ts b/types.d.ts
new file mode 100644
index 0000000..a6ea910
--- /dev/null
+++ b/types.d.ts
@@ -0,0 +1,79 @@
+declare module 'crumbjs' {
+  export type WordLike = string | RegExp | Array<string | RegExp>
+  export type ExceptionHandler = string | ((string: string) => string)
+  export type Exception = [WordLike, ExceptionHandler]
+  export type SuffixerMethod = (
+    word: string,
+    exceptions?: Exception[],
+  ) => string
+
+  export type StopWord = string | RegExp
+
+  export const suffix: {
+    accusative: SuffixerMethod
+    ablative: SuffixerMethod
+    adessive: SuffixerMethod
+    adjective: SuffixerMethod
+    allative: SuffixerMethod
+    finalCasual: SuffixerMethod
+    dative: SuffixerMethod
+    delative: SuffixerMethod
+    elative: SuffixerMethod
+    essiveFormal: SuffixerMethod
+    essiveModal: SuffixerMethod
+    illative: SuffixerMethod
+    inessive: SuffixerMethod
+    instrumentalComitative: SuffixerMethod
+    locative: SuffixerMethod
+    sublative: SuffixerMethod
+    superessive: SuffixerMethod
+    terminative: SuffixerMethod
+    translative: SuffixerMethod
+    privative: SuffixerMethod
+    plural: SuffixerMethod
+    genitive: SuffixerMethod
+    temporal: SuffixerMethod
+    sociative: SuffixerMethod
+    distributiveTemporal: SuffixerMethod
+    distributive: SuffixerMethod
+    formal: SuffixerMethod
+    modalEssive: SuffixerMethod
+    multiplicative: SuffixerMethod
+    frequentative: SuffixerMethod
+  }
+
+  export const grade: {
+    comparative: SuffixerMethod
+    superlative: SuffixerMethod
+    excessive: SuffixerMethod
+  }
+
+  export function getNumberWithWords(number: number): string
+
+  export function getSyllables(
+    word: string,
+    options?: {
+      stopWords?: StopWord | StopWord[]
+      formatted?: true
+      hyphenCharacter?: string
+    },
+  ): string
+
+  export function getSyllables(
+    word: string,
+    options?: {
+      stopWords?: StopWord | StopWord[]
+      formatted?: false
+      hyphenCharacter?: string
+    },
+  ): string[]
+
+  export function getSyllables(
+    word: string,
+    options?: {
+      stopWords?: StopWord | StopWord[]
+      formatted?: boolean
+      hyphenCharacter?: string
+    },
+  ): string | string[]
+}