diff --git a/.devcontainer/aarch64/devcontainer-lock.json b/.devcontainer/aarch64/devcontainer-lock.json
new file mode 100644
index 0000000..f6c7208
--- /dev/null
+++ b/.devcontainer/aarch64/devcontainer-lock.json
@@ -0,0 +1,14 @@
+{
+  "features": {
+    "ghcr.io/devcontainers/features/common-utils:2": {
+      "version": "2.5.9",
+      "resolved": "ghcr.io/devcontainers/features/common-utils@sha256:cb0c4d3c276f157eed17935747e364178d75fee17f55c4e129966f64633deb3a",
+      "integrity": "sha256:cb0c4d3c276f157eed17935747e364178d75fee17f55c4e129966f64633deb3a"
+    },
+    "ghcr.io/devcontainers/features/git:1": {
+      "version": "1.3.8",
+      "resolved": "ghcr.io/devcontainers/features/git@sha256:fd75977de13a9979000e0e78baf949adb0ca71d2398995fa22e0a36d7e7e7fe2",
+      "integrity": "sha256:fd75977de13a9979000e0e78baf949adb0ca71d2398995fa22e0a36d7e7e7fe2"
+    }
+  }
+}
diff --git a/.devcontainer/aarch64/devcontainer.json b/.devcontainer/aarch64/devcontainer.json
index 53a6595..b9a3c04 100644
--- a/.devcontainer/aarch64/devcontainer.json
+++ b/.devcontainer/aarch64/devcontainer.json
@@ -1,6 +1,6 @@
 {
   "name": "Swift",
-  "image": "swift:6.0",
+  "image": "swift:6.1",
   "features": {
     "ghcr.io/devcontainers/features/common-utils:2": {
       "installZsh": "false",
diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index bb5b6e4..6ca965f 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -12,7 +12,7 @@ jobs:
   test-linux:
     name: "Test Linux"
     runs-on: ubuntu-latest
-    container: swift:6.0-jammy
+    container: swift:6.1-noble
     steps:
       - name: Checkout
         uses: actions/checkout@v4
diff --git a/Package.resolved b/Package.resolved
index b4c6f76..8e02992 100644
--- a/Package.resolved
+++ b/Package.resolved
@@ -1,13 +1,13 @@
 {
-  "originHash" : "80abcad025789e7c46ac8ef30ab5480c5c71e5f67deab23941ea02aa0d3e4c09",
+  "originHash" : "ec37b77adff7adafffd884de38574520cb462bcbeb6311eb58779537fcfd6cdd",
   "pins" : [
     {
       "identity" : "swift-asn1",
       "kind" : "remoteSourceControl",
       "location" : "https://github.com/apple/swift-asn1.git",
       "state" : {
-        "revision" : "f70225981241859eb4aa1a18a75531d26637c8cc",
-        "version" : "1.4.0"
+        "revision" : "a9a5efd40eaf558a2bcd48d64b1d1646be686008",
+        "version" : "1.7.1"
       }
     },
     {
@@ -15,8 +15,8 @@
       "kind" : "remoteSourceControl",
       "location" : "https://github.com/apple/swift-certificates.git",
       "state" : {
-        "revision" : "4b092f15164144c24554e0a75e080a960c5190a6",
-        "version" : "1.14.0"
+        "revision" : "449dbbecd0f31e82b510ada227ca152caa8b5e98",
+        "version" : "1.19.4"
       }
     },
     {
@@ -24,8 +24,8 @@
       "kind" : "remoteSourceControl",
       "location" : "https://github.com/apple/swift-crypto.git",
       "state" : {
-        "revision" : "d1c6b70f7c5f19fb0b8750cb8dcdf2ea6e2d8c34",
-        "version" : "3.15.0"
+        "revision" : "47d3869a7291f085c1fb9fb1e6d3b97a793f45c6",
+        "version" : "4.5.1"
       }
     },
     {
@@ -33,8 +33,8 @@
       "kind" : "remoteSourceControl",
       "location" : "https://github.com/apple/swift-system.git",
       "state" : {
-        "revision" : "395a77f0aa927f0ff73941d7ac35f2b46d47c9db",
-        "version" : "1.6.3"
+        "revision" : "869129b7bf4ecc57b97d0193ad29690ca2134750",
+        "version" : "1.8.1"
       }
     },
     {
@@ -42,8 +42,8 @@
       "kind" : "remoteSourceControl",
       "location" : "https://github.com/adam-fowler/swift-zip-archive.git",
       "state" : {
-        "revision" : "2cf559f47443d99924950c4114aba1af3e688c7d",
-        "version" : "0.6.3"
+        "revision" : "0958a719c924d2b3cb27cd7d9f76b4cfb04549f2",
+        "version" : "0.8.1"
       }
     }
   ],
diff --git a/Package.swift b/Package.swift
index 82452f1..6d4b38e 100644
--- a/Package.swift
+++ b/Package.swift
@@ -1,8 +1,19 @@
-// swift-tools-version: 6.0
+// swift-tools-version: 6.1
 // The swift-tools-version declares the minimum version of Swift required to build this package.
 
 import PackageDescription
 
+let swiftSettings: [SwiftSetting] = [
+    // https://github.com/swiftlang/swift-evolution/blob/main/proposals/0335-existential-any.md
+    .enableUpcomingFeature("ExistentialAny"),
+
+    // https://github.com/swiftlang/swift-evolution/blob/main/proposals/0409-access-level-on-imports.md
+    .enableUpcomingFeature("InternalImportsByDefault"),
+
+    // https://github.com/swiftlang/swift-evolution/blob/main/proposals/0444-member-import-visibility.md
+    .enableUpcomingFeature("MemberImportVisibility"),
+]
+
 let package = Package(
     name: "PassKit",
     platforms: [
@@ -15,12 +26,13 @@ let package = Package(
         .library(name: "PassHelpers", targets: ["PassHelpers"]),
     ],
     dependencies: [
-        .package(url: "https://github.com/adam-fowler/swift-zip-archive.git", .upToNextMajor(from: "0.6.3")),
-        .package(url: "https://github.com/apple/swift-certificates.git", from: "1.14.0")
+        .package(url: "https://github.com/adam-fowler/swift-zip-archive.git", .upToNextMajor(from: "0.8.1")),
+        .package(url: "https://github.com/apple/swift-certificates.git", from: "1.19.0")
     ],
     targets: [
         .target(
-            name: "PassCore"
+            name: "PassCore",
+            swiftSettings: swiftSettings
         ),
         .target(
             name: "PassGen",
@@ -31,14 +43,16 @@ let package = Package(
             ],
             resources: [
                 .process("Resources")
-            ]
+            ],
+            swiftSettings: swiftSettings
         ),
         .target(
             name: "PassHelpers",
             dependencies: [
                 .target(name: "PassCore"),
                 .target(name: "PassGen")
-            ]
+            ],
+            swiftSettings: swiftSettings
         ),
         .testTarget(
             name: "PassKitTests",
@@ -47,7 +61,8 @@ let package = Package(
                 .target(name: "PassGen"),
                 .product(name: "X509", package: "swift-certificates")
             ],
-            resources: [.process("Resources")]
+            resources: [.process("Resources")],
+            swiftSettings: swiftSettings
         ),
     ]
 )
diff --git a/Sources/PassCore/Extensions.swift b/Sources/PassCore/Extensions.swift
index b621645..5448455 100644
--- a/Sources/PassCore/Extensions.swift
+++ b/Sources/PassCore/Extensions.swift
@@ -2,9 +2,9 @@
 // Copyright (c) 2025 hiimtmac inc.
 
 #if canImport(FoundationEssentials)
-import FoundationEssentials
+public import FoundationEssentials
 #else
-import Foundation
+public import Foundation
 #endif
 
 extension JSONEncoder {
diff --git a/Sources/PassCore/Pass.swift b/Sources/PassCore/Pass.swift
index 8d1db17..05c190a 100755
--- a/Sources/PassCore/Pass.swift
+++ b/Sources/PassCore/Pass.swift
@@ -2,9 +2,9 @@
 // Copyright (c) 2025 hiimtmac inc.
 
 #if canImport(FoundationEssentials)
-import FoundationEssentials
+public import FoundationEssentials
 #else
-import Foundation
+public import Foundation
 #endif
 
 // https://developer.apple.com/documentation/walletpasses/pass
diff --git a/Sources/PassCore/PassFieldContent.swift b/Sources/PassCore/PassFieldContent.swift
index fafe621..579489f 100755
--- a/Sources/PassCore/PassFieldContent.swift
+++ b/Sources/PassCore/PassFieldContent.swift
@@ -2,9 +2,9 @@
 // Copyright (c) 2025 hiimtmac inc.
 
 #if canImport(FoundationEssentials)
-import FoundationEssentials
+public import FoundationEssentials
 #else
-import Foundation
+public import Foundation
 #endif
 
 // https://developer.apple.com/documentation/walletpasses/passfieldcontent
diff --git a/Sources/PassCore/RelevantDate.swift b/Sources/PassCore/RelevantDate.swift
index 5090ab6..e036a5a 100644
--- a/Sources/PassCore/RelevantDate.swift
+++ b/Sources/PassCore/RelevantDate.swift
@@ -1,7 +1,11 @@
 // RelevantDate.swift
 // Copyright (c) 2025 hiimtmac inc.
 
-import Foundation
+#if canImport(FoundationEssentials)
+public import FoundationEssentials
+#else
+public import Foundation
+#endif
 
 extension Pass {
     /// https://developer.apple.com/documentation/walletpasses/pass/relevantdates-data.dictionary
diff --git a/Sources/PassCore/SemanticTags.swift b/Sources/PassCore/SemanticTags.swift
index fffe464..2279a1f 100644
--- a/Sources/PassCore/SemanticTags.swift
+++ b/Sources/PassCore/SemanticTags.swift
@@ -1,7 +1,11 @@
 // SemanticTags.swift
 // Copyright (c) 2025 hiimtmac inc.
 
-import Foundation
+#if canImport(FoundationEssentials)
+public import FoundationEssentials
+#else
+public import Foundation
+#endif
 
 // https://developer.apple.com/documentation/walletpasses/semantictags
 /// An object that contains machine-readable metadata the system uses to offer a pass and suggest related actions.
diff --git a/Sources/PassCore/UpcomingPassInformationEntry.swift b/Sources/PassCore/UpcomingPassInformationEntry.swift
index 0b92a5d..a8e8ad4 100644
--- a/Sources/PassCore/UpcomingPassInformationEntry.swift
+++ b/Sources/PassCore/UpcomingPassInformationEntry.swift
@@ -1,7 +1,12 @@
 // UpcomingPassInformationEntry.swift
 // Copyright (c) 2025 hiimtmac inc.
 
-import Foundation
+#if canImport(FoundationEssentials)
+public import FoundationEssentials
+#else
+public import Foundation
+#endif
+
 
 // https://developer.apple.com/documentation/walletpasses/upcomingpassinformationentry
 /// An object that represents the ordered list of all upcoming pass information entries.
diff --git a/Sources/PassGen/Manifest.swift b/Sources/PassGen/Manifest.swift
index 443747a..124ace4 100644
--- a/Sources/PassGen/Manifest.swift
+++ b/Sources/PassGen/Manifest.swift
@@ -2,6 +2,7 @@
 // Copyright (c) 2025 hiimtmac inc.
 
 import Crypto
+
 #if canImport(FoundationEssentials)
 import FoundationEssentials
 #else
@@ -13,7 +14,9 @@ struct Manifest {
 
     mutating func addHash(name: String, data: Data) {
         let hashData = Insecure.SHA1.hash(data: data)
-        hashes[name] = hashData.map { String(format: "%02hhx", $0) }.joined()
+        hashes[name] = hashData.map { String($0, radix: 16, uppercase: false) }
+            .map { $0.count == 1 ? "0" + $0 : $0 }
+            .joined()
     }
 
     func makeData() throws -> Data {
diff --git a/Sources/PassGen/PassGenerator.swift b/Sources/PassGen/PassGenerator.swift
index ad6d21b..ec1a682 100644
--- a/Sources/PassGen/PassGenerator.swift
+++ b/Sources/PassGen/PassGenerator.swift
@@ -4,11 +4,12 @@
 import _CryptoExtras
 // TODO: `Bundle` is not available in FoundationEssentials
 // #if canImport(FoundationEssentials)
-// import FoundationEssentials
+// public import FoundationEssentials
 // #else
-import Foundation
+public import Foundation
 // #endif
-import PassCore
+public import PassCore
+import SwiftASN1
 import X509
 import ZipArchive
 
diff --git a/Sources/PassGen/PassReader.swift b/Sources/PassGen/PassReader.swift
index 242dbef..e34ef35 100644
--- a/Sources/PassGen/PassReader.swift
+++ b/Sources/PassGen/PassReader.swift
@@ -2,11 +2,12 @@
 // Copyright (c) 2025 hiimtmac inc.
 
 #if canImport(FoundationEssentials)
-import FoundationEssentials
+public import FoundationEssentials
 #else
-import Foundation
+public import Foundation
 #endif
-import PassCore
+public import PassCore
+import SystemPackage
 import ZipArchive
 
 extension DecodingError {
diff --git a/Sources/PassHelpers/ImageSize.swift b/Sources/PassHelpers/ImageSize.swift
index a37d947..d819201 100644
--- a/Sources/PassHelpers/ImageSize.swift
+++ b/Sources/PassHelpers/ImageSize.swift
@@ -1,7 +1,7 @@
 // ImageSize.swift
 // Copyright (c) 2025 hiimtmac inc.
 
-import Foundation
+public import Foundation
 
 public enum ImageSize: Hashable {
     case icon
diff --git a/Sources/PassHelpers/Pass+Extensions.swift b/Sources/PassHelpers/Pass+Extensions.swift
index 710834e..39ca437 100644
--- a/Sources/PassHelpers/Pass+Extensions.swift
+++ b/Sources/PassHelpers/Pass+Extensions.swift
@@ -1,8 +1,12 @@
 // Pass+Extensions.swift
 // Copyright (c) 2025 hiimtmac inc.
 
-import Foundation
-import PassCore
+#if canImport(FoundationEssentials)
+public import FoundationEssentials
+#else
+public import Foundation
+#endif
+public import PassCore
 
 extension Pass {
     public static func boardingPass(
diff --git a/Sources/PassHelpers/PassContainer.swift b/Sources/PassHelpers/PassContainer.swift
index 7a14394..b675ee7 100644
--- a/Sources/PassHelpers/PassContainer.swift
+++ b/Sources/PassHelpers/PassContainer.swift
@@ -1,8 +1,12 @@
 // PassContainer.swift
 // Copyright (c) 2025 hiimtmac inc.
 
+#if canImport(FoundationEssentials)
+import FoundationEssentials
+#else
 import Foundation
-import PassCore
+#endif
+public import PassCore
 
 // https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/PassKit_PG/index.html#//apple_ref/doc/uid/TP40012195-CH1-SW1
 
diff --git a/Sources/PassHelpers/PassFieldContent+Extensions.swift b/Sources/PassHelpers/PassFieldContent+Extensions.swift
index 32eb77f..3bf88ae 100644
--- a/Sources/PassHelpers/PassFieldContent+Extensions.swift
+++ b/Sources/PassHelpers/PassFieldContent+Extensions.swift
@@ -1,8 +1,12 @@
 // PassFieldContent+Extensions.swift
 // Copyright (c) 2025 hiimtmac inc.
 
-import Foundation
-import PassCore
+#if canImport(FoundationEssentials)
+public import FoundationEssentials
+#else
+public import Foundation
+#endif
+public import PassCore
 
 // MARK: - String
 
diff --git a/Sources/PassHelpers/PassFields+Extensions.swift b/Sources/PassHelpers/PassFields+Extensions.swift
index 2991bbf..5626700 100644
--- a/Sources/PassHelpers/PassFields+Extensions.swift
+++ b/Sources/PassHelpers/PassFields+Extensions.swift
@@ -1,7 +1,7 @@
 // PassFields+Extensions.swift
 // Copyright (c) 2025 hiimtmac inc.
 
-import PassCore
+public import PassCore
 
 extension PassFields {
     public static func boardingPass(
diff --git a/Sources/PassHelpers/SemanticTags+Extensions.swift b/Sources/PassHelpers/SemanticTags+Extensions.swift
index c4bfa34..75c5886 100644
--- a/Sources/PassHelpers/SemanticTags+Extensions.swift
+++ b/Sources/PassHelpers/SemanticTags+Extensions.swift
@@ -1,8 +1,12 @@
 // SemanticTags+Extensions.swift
 // Copyright (c) 2025 hiimtmac inc.
 
-import Foundation
-import PassCore
+#if canImport(FoundationEssentials)
+public import FoundationEssentials
+#else
+public import Foundation
+#endif
+public import PassCore
 
 extension SemanticTags {
     public static func eventSemantics(
diff --git a/Sources/PassHelpers/UTType+Extensions.swift b/Sources/PassHelpers/UTType+Extensions.swift
index 6db0a6e..ffe78ee 100644
--- a/Sources/PassHelpers/UTType+Extensions.swift
+++ b/Sources/PassHelpers/UTType+Extensions.swift
@@ -2,7 +2,7 @@
 // Copyright (c) 2025 hiimtmac inc.
 
 #if canImport(UniformTypeIdentifiers)
-import UniformTypeIdentifiers
+public import UniformTypeIdentifiers
 
 extension UTType {
     public static let pkpass = UTType("com.apple.pkpass-data")!
diff --git a/Tests/PassKitTests/GeneratorTests.swift b/Tests/PassKitTests/GeneratorTests.swift
index 22a3b18..48232a6 100644
--- a/Tests/PassKitTests/GeneratorTests.swift
+++ b/Tests/PassKitTests/GeneratorTests.swift
@@ -3,6 +3,7 @@
 
 import Foundation
 import Testing
+import PassCore
 @testable import PassGen
 
 @Suite
diff --git a/Tests/PassKitTests/ReaderTests.swift b/Tests/PassKitTests/ReaderTests.swift
index a8bb201..3974878 100644
--- a/Tests/PassKitTests/ReaderTests.swift
+++ b/Tests/PassKitTests/ReaderTests.swift
@@ -3,6 +3,7 @@
 
 import Foundation
 import Testing
+import PassCore
 @testable import PassGen
 
 @Suite