diff --git a/Sources/GISTools/GeoJson/Feature.swift b/Sources/GISTools/GeoJson/Feature.swift
index 2006a45..0411435 100644
--- a/Sources/GISTools/GeoJson/Feature.swift
+++ b/Sources/GISTools/GeoJson/Feature.swift
@@ -1,7 +1,10 @@
 import Foundation
 
 /// A GeoJSON `Feature`.
-public struct Feature: GeoJson, Identifiable {
+public struct Feature:
+    GeoJson,
+    Identifiable
+{
 
     /// A GeoJSON identifier that can either be a string or number.
     ///
@@ -104,7 +107,7 @@ public struct Feature: GeoJson, Identifiable {
     public init(
         _ geometry: GeoJsonGeometry,
         id: Identifier? = nil,
-        properties: [String: Any] = [:],
+        properties: [String: Sendable] = [:],
         calculateBoundingBox: Bool = false)
     {
         self.geometry = geometry
@@ -121,14 +124,14 @@ public struct Feature: GeoJson, Identifiable {
     }
 
     public init?(json: Any?, calculateBoundingBox: Bool = false) {
-        guard let geoJson = json as? [String: Any],
+        guard let geoJson = json as? [String: Sendable],
               Feature.isValid(geoJson: geoJson),
               let geometry: GeoJsonGeometry = Feature.tryCreateGeometry(json: geoJson["geometry"])
         else { return nil }
 
         self.geometry = geometry
         self.id = Identifier(value: geoJson["id"])
-        self.properties = (geoJson["properties"] as? [String: Any]) ?? [:]
+        self.properties = (geoJson["properties"] as? [String: Sendable]) ?? [:]
         self.boundingBox = Feature.tryCreate(json: geoJson["bbox"])
 
         if calculateBoundingBox, self.boundingBox == nil {
@@ -223,14 +226,14 @@ extension Feature {
 extension Feature {
 
     /// Returns a property by key.
-    public func property<T>(for key: String) -> T? {
+    public func property<T: Sendable>(for key: String) -> T? {
         return properties[key] as? T
     }
 
     /// Set a property key/value pair.
     ///
     /// - important: `value` must be a valid JSON object or serialization will fail.
-    public mutating func setProperty(_ value: Any?, for key: String) {
+    public mutating func setProperty(_ value: Sendable?, for key: String) {
         var updatedProperties = properties
         updatedProperties[key] = value
         properties = updatedProperties
@@ -238,7 +241,7 @@ extension Feature {
 
     /// Remove a property from the Feature.
     @discardableResult
-    public mutating func removeProperty(for key: String) -> Any? {
+    public mutating func removeProperty(for key: String) -> Sendable? {
         var updatedProperties = properties
         let previous = updatedProperties.removeValue(forKey: key)
         properties = updatedProperties
@@ -246,7 +249,7 @@ extension Feature {
     }
 
     /// Returns a property by key.
-    public subscript<T>(key: String) -> T? {
+    public subscript<T: Sendable>(key: String) -> T? {
         get {
             return property(for: key)
         }
diff --git a/Sources/GISTools/GeoJson/FeatureCollection.swift b/Sources/GISTools/GeoJson/FeatureCollection.swift
index c379320..898d3e1 100644
--- a/Sources/GISTools/GeoJson/FeatureCollection.swift
+++ b/Sources/GISTools/GeoJson/FeatureCollection.swift
@@ -94,7 +94,7 @@ public struct FeatureCollection:
     }
 
     // To prevent an infinite recursion.
-    init?(geoJson: [String: Any], calculateBoundingBox: Bool = false) {
+    init?(geoJson: [String: Sendable], calculateBoundingBox: Bool = false) {
         guard FeatureCollection.isValid(geoJson: geoJson),
               let features: [Feature] = FeatureCollection.tryCreate(json: geoJson["features"])
         else { return nil }
diff --git a/Sources/GISTools/GeoJson/GeoJson.swift b/Sources/GISTools/GeoJson/GeoJson.swift
index 52c58c5..ecb441a 100644
--- a/Sources/GISTools/GeoJson/GeoJson.swift
+++ b/Sources/GISTools/GeoJson/GeoJson.swift
@@ -91,14 +91,14 @@ extension GeoJson {
 extension GeoJson {
 
     /// Any foreign member by key.
-    public func foreignMember<T>(for key: String) -> T? {
+    public func foreignMember<T: Sendable>(for key: String) -> T? {
         return foreignMembers[key] as? T
     }
 
     /// Set a foreign member key/value pair.
     ///
     /// - important: `value` must be a valid JSON object or serialization will fail.
-    public mutating func setForeignMember(_ value: Any?, for key: String) {
+    public mutating func setForeignMember(_ value: Sendable?, for key: String) {
         var updatedProperties = foreignMembers
         updatedProperties[key] = value
         foreignMembers = updatedProperties
@@ -106,7 +106,7 @@ extension GeoJson {
 
     /// Remove a foreign member from the receiver.
     @discardableResult
-    public mutating func removeForeignMember(for key: String) -> Any? {
+    public mutating func removeForeignMember(for key: String) -> Sendable? {
         var updatedProperties = foreignMembers
         let previous = updatedProperties.removeValue(forKey: key)
         foreignMembers = updatedProperties
@@ -114,7 +114,7 @@ extension GeoJson {
     }
 
     /// Any foreign member by subscript.
-    public subscript<T>(foreignMember key: String) -> T? {
+    public subscript<T: Sendable>(foreignMember key: String) -> T? {
         get {
             return foreignMember(for: key)
         }
@@ -228,7 +228,7 @@ extension GeoJson {
 
     /// Try to create a GeoJSON object from any JSON object.
     public static func tryCreate(json: Any?) -> GeoJson? {
-        if let geoJson = json as? [String: Any],
+        if let geoJson = json as? [String: Sendable],
            let typeString = geoJson["type"] as? String,
            let type = GeoJsonType(rawValue: typeString),
            type != .invalid
@@ -251,7 +251,7 @@ extension GeoJson {
 
     /// Try to create a GeoJSON geometry from any JSON object.
     public static func tryCreateGeometry(json: Any?) -> GeoJsonGeometry? {
-        if let geoJson = json as? [String: Any],
+        if let geoJson = json as? [String: Sendable],
            let typeString = geoJson["type"] as? String,
            let type = GeoJsonType(rawValue: typeString),
            type != .invalid
diff --git a/Sources/GISTools/GeoJson/GeometryCollection.swift b/Sources/GISTools/GeoJson/GeometryCollection.swift
index ae27909..d5f3556 100644
--- a/Sources/GISTools/GeoJson/GeometryCollection.swift
+++ b/Sources/GISTools/GeoJson/GeometryCollection.swift
@@ -41,7 +41,7 @@ public struct GeometryCollection: GeoJsonGeometry {
     }
 
     public init?(json: Any?, calculateBoundingBox: Bool = false) {
-        guard let geoJson = json as? [String: Any],
+        guard let geoJson = json as? [String: Sendable],
               GeometryCollection.isValid(geoJson: geoJson),
               let geometries: [GeoJsonGeometry] = GeometryCollection.tryCreate(json: geoJson["geometries"])
         else { return nil }
diff --git a/Sources/GISTools/GeoJson/LineString.swift b/Sources/GISTools/GeoJson/LineString.swift
index 8974cab..7704b45 100644
--- a/Sources/GISTools/GeoJson/LineString.swift
+++ b/Sources/GISTools/GeoJson/LineString.swift
@@ -94,7 +94,7 @@ public struct LineString:
     }
 
     public init?(json: Any?, calculateBoundingBox: Bool = false) {
-        guard let geoJson = json as? [String: Any],
+        guard let geoJson = json as? [String: Sendable],
               LineString.isValid(geoJson: geoJson),
               let coordinates: [Coordinate3D] = LineString.tryCreate(json: geoJson["coordinates"])
         else { return nil }
diff --git a/Sources/GISTools/GeoJson/MultiLineString.swift b/Sources/GISTools/GeoJson/MultiLineString.swift
index e9f7855..527e743 100644
--- a/Sources/GISTools/GeoJson/MultiLineString.swift
+++ b/Sources/GISTools/GeoJson/MultiLineString.swift
@@ -91,7 +91,7 @@ public struct MultiLineString:
     }
 
     public init?(json: Any?, calculateBoundingBox: Bool = false) {
-        guard let geoJson = json as? [String: Any],
+        guard let geoJson = json as? [String: Sendable],
               MultiLineString.isValid(geoJson: geoJson),
               let coordinates: [[Coordinate3D]] = MultiLineString.tryCreate(json: geoJson["coordinates"])
         else { return nil }
diff --git a/Sources/GISTools/GeoJson/MultiPoint.swift b/Sources/GISTools/GeoJson/MultiPoint.swift
index 102f2f2..78a1aaa 100644
--- a/Sources/GISTools/GeoJson/MultiPoint.swift
+++ b/Sources/GISTools/GeoJson/MultiPoint.swift
@@ -73,7 +73,7 @@ public struct MultiPoint:
     }
 
     public init?(json: Any?, calculateBoundingBox: Bool = false) {
-        guard let geoJson = json as? [String: Any],
+        guard let geoJson = json as? [String: Sendable],
               MultiPoint.isValid(geoJson: geoJson),
               let coordinates: [Coordinate3D] = MultiPoint.tryCreate(json: geoJson["coordinates"])
         else { return nil }
diff --git a/Sources/GISTools/GeoJson/MultiPolygon.swift b/Sources/GISTools/GeoJson/MultiPolygon.swift
index 80baa26..6d63d68 100644
--- a/Sources/GISTools/GeoJson/MultiPolygon.swift
+++ b/Sources/GISTools/GeoJson/MultiPolygon.swift
@@ -76,7 +76,7 @@ public struct MultiPolygon:
     }
 
     public init?(json: Any?, calculateBoundingBox: Bool = false) {
-        guard let geoJson = json as? [String: Any],
+        guard let geoJson = json as? [String: Sendable],
               MultiPolygon.isValid(geoJson: geoJson),
               let coordinates: [[[Coordinate3D]]] = MultiPolygon.tryCreate(json: geoJson["coordinates"])
         else { return nil }
diff --git a/Sources/GISTools/GeoJson/Point.swift b/Sources/GISTools/GeoJson/Point.swift
index fb21fff..7b17d30 100644
--- a/Sources/GISTools/GeoJson/Point.swift
+++ b/Sources/GISTools/GeoJson/Point.swift
@@ -43,7 +43,7 @@ public struct Point: PointGeometry {
     }
 
     public init?(json: Any?, calculateBoundingBox: Bool = false) {
-        guard let geoJson = json as? [String: Any],
+        guard let geoJson = json as? [String: Sendable],
               Point.isValid(geoJson: geoJson),
               let coordinate: Coordinate3D = Point.tryCreate(json: geoJson["coordinates"])
         else { return nil }
diff --git a/Sources/GISTools/GeoJson/Polygon.swift b/Sources/GISTools/GeoJson/Polygon.swift
index 75e644d..5032cc0 100644
--- a/Sources/GISTools/GeoJson/Polygon.swift
+++ b/Sources/GISTools/GeoJson/Polygon.swift
@@ -92,7 +92,7 @@ public struct Polygon:
     }
 
     public init?(json: Any?, calculateBoundingBox: Bool = false) {
-        guard let geoJson = json as? [String: Any],
+        guard let geoJson = json as? [String: Sendable],
               Polygon.isValid(geoJson: geoJson),
               let coordinates: [[Coordinate3D]] = Polygon.tryCreate(json: geoJson["coordinates"])
         else { return nil }
diff --git a/Sources/GISTools/GeoJson/WKBCoder.swift b/Sources/GISTools/GeoJson/WKBCoder.swift
index 1247d8e..55d5a5e 100644
--- a/Sources/GISTools/GeoJson/WKBCoder.swift
+++ b/Sources/GISTools/GeoJson/WKBCoder.swift
@@ -73,7 +73,7 @@ extension Feature {
         sourceSrid: Int?,
         targetProjection: Projection = .epsg4326,
         id: Identifier? = nil,
-        properties: [String: Any] = [:],
+        properties: [String: Sendable] = [:],
         calculateBoundingBox: Bool = false)
     {
         guard let geometry = try? WKBCoder.decode(wkb: wkb, sourceSrid: sourceSrid, targetProjection: targetProjection) else { return nil }
@@ -88,7 +88,7 @@ extension Feature {
         sourceProjection: Projection,
         targetProjection: Projection = .epsg4326,
         id: Identifier? = nil,
-        properties: [String: Any] = [:],
+        properties: [String: Sendable] = [:],
         calculateBoundingBox: Bool = false)
     {
         guard let geometry = try? WKBCoder.decode(wkb: wkb, sourceProjection: sourceProjection, targetProjection: targetProjection) else { return nil }
@@ -172,7 +172,7 @@ extension Data {
         sourceSrid: Int?,
         targetProjection: Projection = .epsg4326,
         id: Feature.Identifier? = nil,
-        properties: [String: Any] = [:])
+        properties: [String: Sendable] = [:])
         -> Feature?
     {
         Feature(wkb: self, sourceSrid: sourceSrid, targetProjection: targetProjection, id: id, properties: properties)
@@ -185,7 +185,7 @@ extension Data {
         sourceProjection: Projection,
         targetProjection: Projection = .epsg4326,
         id: Feature.Identifier? = nil,
-        properties: [String: Any] = [:])
+        properties: [String: Sendable] = [:])
         -> Feature?
     {
         Feature(wkb: self, sourceProjection: sourceProjection, targetProjection: targetProjection, id: id, properties: properties)
diff --git a/Sources/GISTools/GeoJson/WKTCoder.swift b/Sources/GISTools/GeoJson/WKTCoder.swift
index 947212a..0184973 100644
--- a/Sources/GISTools/GeoJson/WKTCoder.swift
+++ b/Sources/GISTools/GeoJson/WKTCoder.swift
@@ -73,7 +73,7 @@ extension Feature {
         sourceSrid: Int?,
         targetProjection: Projection = .epsg4326,
         id: Identifier? = nil,
-        properties: [String: Any] = [:],
+        properties: [String: Sendable] = [:],
         calculateBoundingBox: Bool = false)
     {
         guard let geometry = try? WKTCoder.decode(wkt: wkt, sourceSrid: sourceSrid, targetProjection: targetProjection) else { return nil }
@@ -88,7 +88,7 @@ extension Feature {
         sourceProjection: Projection,
         targetProjection: Projection = .epsg4326,
         id: Identifier? = nil,
-        properties: [String: Any] = [:],
+        properties: [String: Sendable] = [:],
         calculateBoundingBox: Bool = false)
     {
         guard let geometry = try? WKTCoder.decode(wkt: wkt, sourceProjection: sourceProjection, targetProjection: targetProjection) else { return nil }
@@ -182,7 +182,7 @@ extension String {
         sourceSrid: Int?,
         targetProjection: Projection = .epsg4326,
         id: Feature.Identifier? = nil,
-        properties: [String: Any] = [:])
+        properties: [String: Sendable] = [:])
         -> Feature?
     {
         Feature(wkt: self, sourceSrid: sourceSrid, targetProjection: targetProjection, id: id, properties: properties)
@@ -195,7 +195,7 @@ extension String {
         sourceProjection: Projection,
         targetProjection: Projection = .epsg4326,
         id: Feature.Identifier? = nil,
-        properties: [String: Any] = [:])
+        properties: [String: Sendable] = [:])
         -> Feature?
     {
         Feature(wkt: self, sourceProjection: sourceProjection, targetProjection: targetProjection, id: id, properties: properties)
diff --git a/Tests/GISToolsTests/Helpers/TestData.swift b/Tests/GISToolsTests/Helpers/TestData.swift
index 342b4b7..60c74d6 100644
--- a/Tests/GISToolsTests/Helpers/TestData.swift
+++ b/Tests/GISToolsTests/Helpers/TestData.swift
@@ -43,7 +43,7 @@ class TestData {
     // MARK: -
 
     class func stringFromFile(package: String, name: String) -> String {
-        let path = URL(fileURLWithPath: #file)
+        let path = URL(fileURLWithPath: #filePath)
             .deletingLastPathComponent()
             .deletingLastPathComponent()
             .appendingPathComponent("TestData")
@@ -65,13 +65,13 @@ class TestData {
     }
 
     class func dataFromFile(package: String, name: String) -> Data {
-        let path = URL(fileURLWithPath: #file)
+        let path = URL(fileURLWithPath: #filePath)
             .deletingLastPathComponent()
             .deletingLastPathComponent()
             .appendingPathComponent("TestData")
             .appendingPathComponent(package)
             .appendingPathComponent(name)
-        .appendingPathExtension("geojson")
+            .appendingPathExtension("geojson")
 
         do {
             if !(try path.checkResourceIsReachable()) {