HawkN113 · HawkN113 · Jan 10, 2026 · Dec 12, 2025 · Dec 24, 2025 · Dec 24, 2025
diff --git a/.github/workflows/cd.yml b/.github/workflows/cd.yml
@@ -7,22 +7,28 @@ on:
 
 jobs:
   publish:
-    name: Publish to NuGet
+    name: Publish packages (NuGet.org + GitHub)
     runs-on: ubuntu-latest
     permissions:
       id-token: write
       contents: write
+      packages: write
       actions: read
 
     env:
       SOLUTION_NAME: src/HawkN.Iso.Countries.Solution.sln
       NUGET_ORG_USERNAME: HawkN113
 
-      ## Iso.Countries package settings
+      ## Iso.Countries package (Core)
       PACKAGE_COUNTRIES_PROJECT_PATH: src/packages/HawkN.Iso.Countries/HawkN.Iso.Countries.csproj
       PACKAGE_COUNTRIES_NUSPEC_FILE_PATH: HawkN.Iso.Countries.nuspec
       PACKAGE_COUNTRIES_ID: HawkN.Iso.Countries
 
+      ## Iso.Countries.Currencies package (Extension)
+      PACKAGE_COUNTRIES_CURRENCIES_PROJECT_PATH: src/packages/HawkN.Iso.Countries.Currencies/HawkN.Iso.Countries.Currencies.csproj
+      PACKAGE_COUNTRIES_CURRENCIES_NUSPEC_FILE_PATH: HawkN.Iso.Countries.Currencies.nuspec
+      PACKAGE_COUNTRIES_CURRENCIES_ID: HawkN.Iso.Countries.Currencies
+
       OUTPUT_NUGET_DIR: nuget-packages
       NUGET_SOURCE_URL: https://api.nuget.org/v3/index.json
       DOTNET_SKIP_FIRST_TIME_EXPERIENCE: true
@@ -50,17 +56,6 @@ jobs:
           echo "CURRENT_VERSION=$VERSION" >> $GITHUB_ENV
         shell: bash
 
-      - name: Check if package (${{ env.PACKAGE_COUNTRIES_ID }}) version already exists on NuGet.org
-        id: check_nuget
-        run: |
-          PACKAGE_COUNTRIES_ID_LOWER=$(echo "${{ env.PACKAGE_COUNTRIES_ID }}" | tr '[:upper:]' '[:lower:]')
-          STATUS_CODE=$(curl -s -o /dev/null -I -w "%{http_code}" "https://api.nuget.org/v3-flatcontainer/${PACKAGE_COUNTRIES_ID_LOWER}/${{ env.CURRENT_VERSION }}/index.json")
-          if [ "$STATUS_CODE" -eq 200 ]; then
-            echo "Error: Version ${{ env.CURRENT_VERSION }} already exists on NuGet.org!"
-            exit 1
-          fi
-        shell: bash
-
       - name: Restore dependencies
         run: dotnet restore ${{ env.SOLUTION_NAME }}
 
@@ -75,6 +70,15 @@ jobs:
             /p:Version=${{ env.CURRENT_VERSION }} \
             /p:ContinuousIntegrationBuild=true \
             --output ${{ env.OUTPUT_NUGET_DIR }}
+
+      - name: Build and Pack (HawkN.Iso.Countries.Currencies) (Extension)
+        run: |
+          dotnet pack ${{ env.PACKAGE_COUNTRIES_CURRENCIES_PROJECT_PATH }} \
+            --configuration Release \
+            /p:NuspecFile=${{ env.PACKAGE_COUNTRIES_CURRENCIES_NUSPEC_FILE_PATH }} \
+            /p:Version=${{ env.CURRENT_VERSION }} \
+            /p:ContinuousIntegrationBuild=true \
+            --output ${{ env.OUTPUT_NUGET_DIR }}
 
       - name: Generate Release Changelog
         uses: orhun/git-cliff-action@v4
@@ -111,7 +115,9 @@ jobs:
         uses: softprops/action-gh-release@v2
         with:
           body_path: CHANGELOG_RELEASE.md
-          files: ${{ env.OUTPUT_NUGET_DIR }}/${{ env.PACKAGE_COUNTRIES_ID }}.${{ env.CURRENT_VERSION }}.nupkg
+          files: |
+            ${{ env.OUTPUT_NUGET_DIR }}/${{ env.PACKAGE_COUNTRIES_ID }}.${{ env.CURRENT_VERSION }}.nupkg
+            ${{ env.OUTPUT_NUGET_DIR }}/${{ env.PACKAGE_COUNTRIES_CURRENCIES_ID }}.${{ env.CURRENT_VERSION }}.nupkg          
           fail_on_unmatched_files: true
         env:
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
@@ -126,5 +132,28 @@ jobs:
         run: |
           dotnet nuget push "${{ env.OUTPUT_NUGET_DIR }}/${{ env.PACKAGE_COUNTRIES_ID }}.${{ env.CURRENT_VERSION }}.nupkg" \
             --api-key ${{steps.login.outputs.NUGET_API_KEY}} \
-            --source ${{ env.NUGET_SOURCE_URL }}
-        shell: bash
+            --source ${{ env.NUGET_SOURCE_URL }} \
+            --skip-duplicate
+        shell: bash
+
+      - name: Publish package (HawkN.Iso.Countries.Currencies) to NuGet.org (Trusted Publishing)
+        run: |
+          dotnet nuget push "${{ env.OUTPUT_NUGET_DIR }}/${{ env.PACKAGE_COUNTRIES_CURRENCIES_ID }}.${{ env.CURRENT_VERSION }}.nupkg" \
+            --api-key ${{steps.login.outputs.NUGET_API_KEY}} \
+            --source ${{ env.NUGET_SOURCE_URL }} \
+            --skip-duplicate
+        shell: bash
+
+      - name: Publish package (HawkN.Iso.Countries) to GitHub packages
+        run: |
+          dotnet nuget push "${{ env.OUTPUT_NUGET_DIR }}/${{ env.PACKAGE_COUNTRIES_ID }}.${{ env.CURRENT_VERSION }}.nupkg" \
+            --source "https://nuget.pkg.github.com/${{ github.repository_owner }}/index.json" \
+            --api-key ${{ secrets.GITHUB_TOKEN }} \
+            --skip-duplicate
+
+      - name: Publish package (HawkN.Iso.Countries.Currencies) to GitHub Packages
+        run: |
+          dotnet nuget push "${{ env.OUTPUT_NUGET_DIR }}/${{ env.PACKAGE_COUNTRIES_CURRENCIES_ID }}.${{ env.CURRENT_VERSION }}.nupkg" \
+            --source "https://nuget.pkg.github.com/${{ github.repository_owner }}/index.json" \
+            --api-key ${{ secrets.GITHUB_TOKEN }} \
+            --skip-duplicate
diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
@@ -28,8 +28,15 @@ jobs:
 
     env:
       SOLUTION_NAME: src/HawkN.Iso.Countries.Solution.sln
-      PACKAGE_COUNTRY_PROJECT_PATH: src/packages/HawkN.Iso.Countries/HawkN.Iso.Countries.csproj
-      PACKAGE_COUNTRY_NUSPEC_FILE_PATH: HawkN.Iso.Countries.nuspec
+
+      # Iso.Countries package (Core)
+      PACKAGE_COUNTRIES_PROJECT_PATH: src/packages/HawkN.Iso.Countries/HawkN.Iso.Countries.csproj
+      PACKAGE_COUNTRIES_NUSPEC_FILE_PATH: HawkN.Iso.Countries.nuspec
+
+      # Iso.Countries.Currencies package (Extensions)
+      PACKAGE_COUNTRIES_CURRENCIES_PROJECT_PATH: src/packages/HawkN.Iso.Countries.Currencies/HawkN.Iso.Countries.Currencies.csproj
+      PACKAGE_COUNTRIES_CURRENCIES_NUSPEC_FILE_PATH: HawkN.Iso.Countries.Currencies.nuspec
+
       OUTPUT_NUGET_DIR: nuget-packages
       ARTIFACTS_DIR: artifacts
       DOTNET_SKIP_FIRST_TIME_EXPERIENCE: true
@@ -72,7 +79,7 @@ jobs:
     - name: Extract project version (HawkN.Iso.Countries)
       id: get_version
       run: |
-        VERSION=$(sed -n 's/.*<\(VersionPrefix\|Version\)>\([^<]*\)<\/\1>.*/\2/p' ${{ env.PACKAGE_COUNTRY_PROJECT_PATH }} | head -n 1)
+        VERSION=$(sed -n 's/.*<\(VersionPrefix\|Version\)>\([^<]*\)<\/\1>.*/\2/p' ${{ env.PACKAGE_COUNTRIES_PROJECT_PATH }} | head -n 1)
         if [ -z "$VERSION" ]; then
         VERSION=$(date +%Y%m%d)
         fi
@@ -81,7 +88,10 @@ jobs:
       shell: bash
 
     - name: Validate package creation (HawkN.Iso.Countries)
-      run: dotnet pack ${{ env.PACKAGE_COUNTRY_PROJECT_PATH }} /p:NuspecFile=${{ env.PACKAGE_COUNTRY_NUSPEC_FILE_PATH }} /p:ContinuousIntegrationBuild=true --configuration Release --no-build --output ${{ env.OUTPUT_NUGET_DIR }}
+      run: dotnet pack ${{ env.PACKAGE_COUNTRIES_PROJECT_PATH }} /p:NuspecFile=${{ env.PACKAGE_COUNTRIES_NUSPEC_FILE_PATH }} /p:ContinuousIntegrationBuild=true --configuration Release --no-build --output ${{ env.OUTPUT_NUGET_DIR }}
+
+    - name: Validate package creation (HawkN.Iso.Countries.Currencies)
+      run: dotnet pack ${{ env.PACKAGE_COUNTRIES_CURRENCIES_PROJECT_PATH }} /p:NuspecFile=${{ env.PACKAGE_COUNTRIES_CURRENCIES_NUSPEC_FILE_PATH }} /p:ContinuousIntegrationBuild=true --configuration Release --no-build --output ${{ env.OUTPUT_NUGET_DIR }}
 
     - name: Generate CHANGELOG.md
       uses: orhun/git-cliff-action@v4

diff --git a/.gitignore b/.gitignore
@@ -3,10 +3,18 @@ src/packages/HawkN.Iso.Countries/obj/**
 src/packages/HawkN.Iso.Countries/bin/**
 src/packages/HawkN.Iso.Countries.Generators/obj/**
 src/packages/HawkN.Iso.Countries.Generators/bin/**
+src/packages/HawkN.Iso.Countries.Currencies/obj/**
+src/packages/HawkN.Iso.Countries.Currencies/bin/**
+src/packages/HawkN.Iso.Countries.Currencies.Generators/obj/**
+src/packages/HawkN.Iso.Countries.Currencies.Generators/bin/**
 src/tests/HawkN.Iso.Countries.Tests/obj/**
 src/tests/HawkN.Iso.Countries.Tests/bin/**
 src/tests/HawkN.Iso.Countries.Generators.Tests/obj/**
 src/tests/HawkN.Iso.Countries.Generators.Tests/bin/**
+src/tests/HawkN.Iso.Countries.Currencies.Tests/obj/**
+src/tests/HawkN.Iso.Countries.Currencies.Tests/bin/**
+src/tests/HawkN.Iso.Countries.Currencies.Generators.Tests/obj/**
+src/tests/HawkN.Iso.Countries.Currencies.Generators.Tests/bin/**
 src/samples/HawkN.Iso.Countries.Samples.Console/obj/**
 src/samples/HawkN.Iso.Countries.Samples.Console/bin/**
 src/samples/HawkN.Iso.Countries.Samples.WebApi/obj/**

diff --git a/README.md b/README.md
@@ -2,33 +2,48 @@
 [![Build Status](https://img.shields.io/github/actions/workflow/status/HawkN113/HawkN.Iso.Countries/ci.yml?label=Build&style=flat-square)](https://github.com/HawkN113/HawkN.Iso.Countries/actions/workflows/ci.yml)
 [![CodeQL Security](https://img.shields.io/github/actions/workflow/status/HawkN113/HawkN.Iso.Countries/codeql-analysis.yml?label=CodeQL%20Security&style=flat-square)](https://github.com/HawkN113/HawkN.Iso.Countries/actions/workflows/codeql-analysis.yml)
 [![NuGet](https://img.shields.io/nuget/v/HawkN.Iso.Countries?label=HawkN.Iso.Countries&color=blue&style=flat-square)](https://www.nuget.org/packages/HawkN.Iso.Countries/)
-[![Downloads](https://img.shields.io/nuget/dt/HawkN.Iso.Countries?logo=nuget&label=Downloads&color=brightgreen&style=flat-square&cacheSeconds=3600)](https://www.nuget.org/packages/HawkN.Iso.Countries/)
-<br />
+[![Downloads](https://img.shields.io/nuget/dt/HawkN.Iso.Countries?logo=nuget&label=&color=brightgreen&style=flat-square&cacheSeconds=3600)](https://www.nuget.org/packages/HawkN.Iso.Countries/)
+[![NuGet](https://img.shields.io/nuget/v/HawkN.Iso.Countries.Currencies?label=HawkN.Iso.Countries.Currencies&color=blue&style=flat-square)](https://www.nuget.org/packages/HawkN.Iso.Countries.Currencies/)
+[![Downloads](https://img.shields.io/nuget/dt/HawkN.Iso.Countries.Currencies?logo=nuget&label=&color=brightgreen&style=flat-square&cacheSeconds=3600)](https://www.nuget.org/packages/HawkN.Iso.Countries.Currencies/)
+
+</br>
+
 [![NuGet Trusted Publishing](https://img.shields.io/badge/NuGet-Trusted_Publishing-blue?logo=nuget&logoColor=white&style=flat-square)](https://learn.microsoft.com/en-us/nuget/nuget-org/trusted-publishing)
 [![Target Framework](https://img.shields.io/badge/.NET-8.0-512bd4?logo=dotnet&style=flat-square)](https://dotnet.microsoft.com/download)
 [![NuGet Ribbon](https://img.shields.io/badge/NuGet-Small_Size-success?logo=nuget&style=flat-square)](https://www.nuget.org/packages/HawkN.Iso.Countries/)
 [![GitHub license](https://img.shields.io/github/license/HawkN113/HawkN.Iso.Countries?label=License&style=flat-square)](https://github.com/HawkN113/HawkN.Iso.Countries/blob/main/LICENSE)
+[![Data: Unicode CLDR](https://img.shields.io/badge/data-Unicode%20CLDR-lightgrey.svg?label=Data%20license&style=flat-square)](https://unicode.org/license.html)
+[![Data: ODbL](https://img.shields.io/badge/data-ODbL%201.0-orange.svg?label=Data%20license&style=flat-square)](https://opendatacommons.org/licenses/odbl/1-0/)
 
 | ![HawkN.Iso.Countries](docs/img/HawkN.Iso.Countries.png) | **HawkN.Iso.Countries** provides ISO 3166-1 country codes (Alpha-2, Alpha-3), official names, numeric codes (UN M49), and validation services. |
 |--------------------------------------|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
 
 ---
 
-## Features
+## Features 
+### HawkN.Iso.Countries (Core)
 - **Comprehensive Country List** – Provides an up-to-date `ISO 3166-1` country data with numeric codes from `UN M49`.
 - **Strongly Typed Codes** – `TwoLetterCode` and `ThreeLetterCode` enums are generated at compile-time.
 - **Multiple Search Methods** – Lookup by Alpha-2, Alpha-3, Numeric code, or Country Name.
 - **Advanced Validation** – Built-in `ValidationResult` providing detailed feedback for code and name verification.
 - **Ultra-Fast Performance** – O(1) lookups via pre-indexed static dictionaries.
 - **Lightweight & Dependency-Free** – Compatible with .NET 8 and above.
 
+### HawkN.Iso.Countries.Currencies (Extension)
+- **Primary and Secondary Currencies** – Get the main currency or all secondary currencies of a country.
+- **Fast Lookups** – O(1) lookups using pre-indexed dictionaries and HashSet for secondary currencies.
+- **Currency Validation** – Check if a country uses a given currency.
+- **Seamless Integration** – Built to work with `HawkN.Iso.Countries` types (`CountryCode.TwoLetterCode`).
+- **Lightweight & Dependency-Free** – Compatible with .NET 8 and above.
+
 ---
 
 ## Packages
 
-| Package | Description                                                                      |
-|---------------------------------------------------------------------------------------------------|----------------------------------------------------------------------------------|
-| [![NuGet](https://img.shields.io/nuget/v/HawkN.Iso.Countries?label=HawkN.Iso.Countries&color=blue&style=flat-square)](https://www.nuget.org/packages/HawkN.Iso.Countries/) | Main library with country models, validation services, and generated ISO enums (Alpha-2, Alpha-3). |
+| Package                                                                                                                                                                                                     | Description                                                                                                                                                                                                                               |
+|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
+| [![NuGet](https://img.shields.io/nuget/v/HawkN.Iso.Countries?label=HawkN.Iso.Countries&color=blue&style=flat-square)](https://www.nuget.org/packages/HawkN.Iso.Countries/)                                  | Main library with country models, validation services, and generated ISO enums (Alpha-2, Alpha-3).                                                                                                                                        |
+| [![NuGet](https://img.shields.io/nuget/v/HawkN.Iso.Countries.Currencies?label=HawkN.Iso.Countries.Currencies&color=blue&style=flat-square)](https://www.nuget.org/packages/HawkN.Iso.Countries.Currencies/) | Provides ISO-based mapping of primary and secondary currencies for countries.It allows you to quickly retrieve the main currency, secondary currencies, all currencies, or check if a currency is used by a specific country. |
 
 ---
 
@@ -41,17 +56,29 @@ dotnet add package HawkN.Iso.Countries
 ````
 
 ### Required Namespaces
+
+#### HawkN.Iso.Countries (Core)
+
 ```csharp
 using HawkN.Iso.Countries;
 using HawkN.Iso.Countries.Abstractions;
 using HawkN.Iso.Countries.Models;
 using HawkN.Iso.Countries.Extensions;
 ```
+
+#### HawkN.Iso.Countries.Currencies (Extension)
+```csharp
+using HawkN.Iso.Countries;
+using HawkN.Iso.Currencies;
+using HawkN.Iso.Countries.Currencies.Extensions;
+```
 ---
 
 ### Usage Example
 
-#### Registration
+#### HawkN.Iso.Countries (Core)
+
+##### Registration
 Register the service in your DI container:
 ```csharp
 using var host = Host.CreateDefaultBuilder(args)
@@ -61,7 +88,7 @@ using var host = Host.CreateDefaultBuilder(args)
     })
     .Build();
 ```
-#### Retrieval & Search
+##### Retrieval & Search
 The service provides O(1) lookups via pre-indexed dictionaries and efficient partial searching.
 ```csharp
 var service = scope.ServiceProvider.GetRequiredService<ICountryCodeService>();
@@ -98,7 +125,7 @@ var suggestions = service.SearchByName("United")
 // Returns: ["United Arab Emirates", "United Kingdom", "United States", ...]
 ```
 
-#### Validation
+##### Validation
 Check if a code or name is valid and retrieve the model simultaneously:
 ```csharp
 // Validate by Code
@@ -115,7 +142,7 @@ if (!nameResult.IsValid)
     Console.WriteLine($"Error: {nameResult.Reason}"); 
 }
 ```
-#### Fluent String Extensions
+##### Fluent String Extensions
 ```csharp
 string input = "FRA";
 
@@ -136,7 +163,7 @@ if (validationResult.IsValid)
 }
 ```
 
-#### Emoji Flags Support
+##### Emoji Flags Support
 The library provides an easy way to display country flags using standard Unicode Emoji. This works without any external image assets and is perfect for lightweight UI components.
 
 ```csharp
@@ -149,6 +176,31 @@ Console.WriteLine($"{flag} {country.Name}");
 // Output: 🇫🇮 Finland
 ```
 
+#### HawkN.Iso.Countries.Currencies (Extension)
+
+##### Currency mapping
+```csharp
+var country = CountryCode.TwoLetterCode.CH;
+
+// Primary currency
+var primary = country.GetPrimaryCurrency();   // CHF
+
+// Secondary currencies
+var secondary = country.GetSecondaryCurrencies();
+
+// All currencies
+var all = country.GetAllCurrencies();
+
+// Check if used
+bool usesChe = country.IsCurrencyUsedByCountry(CurrencyCode.CHE);
+```
+
+##### Validation
+```csharp
+// Check if used the currency
+bool usesChe = country.IsCurrencyUsedByCountry(CurrencyCode.CHE);
+```
+
 ---
 
 ### Supported countries
@@ -421,11 +473,19 @@ Last updated at `25.12.2025`.
 
 ## License
 
-### Code License
-The source code of `HawkN.Iso.Countries` is licensed under the [MIT License](LICENSE).
+### Code
+This project’s source code is licensed under the [MIT License](LICENSE).
+
+### Data
+This project uses data derived from the following sources:
+
+- **Unicode Common Locale Data Repository (CLDR)**  
+  Licensed under the [Unicode License Agreement](https://unicode.org/license.html).
+
+- Country data (`ISO 3166-1` and `UN M49` numeric codes) is sourced from the [UN Statistics Division – M49 standard](https://unstats.un.org/unsd/methodology/m49/overview)
 
-### Data License
-Country data (`ISO 3166-1` and `UN M49` numeric codes) is sourced from the [UN Statistics Division – M49 standard](https://unstats.un.org/unsd/methodology/m49/overview)
+The above data licenses are **permissive and compatible with MIT-licensed code**  
+when used for reference and code generation.
 
 ---
 
@@ -453,4 +513,4 @@ If you want to contribute code, feel free to submit a Pull Request.
 ### References
 - [ISO 3166 Standard](https://www.iso.org/iso-3166-country-codes.html)
 - [UN Statistics Division – M49 standard](https://unstats.un.org/unsd/methodology/m49/overview)
-- [GitHub Repository](https://github.com/HawkN113/HawkN.Iso.Countries)
+- [GitHub Repository](https://github.com/HawkN113/HawkN.Iso.Countries)