diff --git a/Feature/Sources/IMAP/IMAPError.swift b/Feature/Sources/IMAP/IMAPError.swift
new file mode 100644
index 00000000..2291501c
--- /dev/null
+++ b/Feature/Sources/IMAP/IMAPError.swift
@@ -0,0 +1,17 @@
+/// ``IMAPClient`` throws `IMAPError`.
+public enum IMAPError: Error, CustomStringConvertible, Equatable {
+    case underlying(String)
+    case example
+
+    init(_ error: Error) {
+        self = error as? Self ?? .underlying(error.localizedDescription)
+    }
+
+    // MARK: CustomStringConvertible
+    public var description: String {
+        switch self {
+        case .underlying(let string): "Underlying: \(string)"
+        case .example: "Example"
+        }
+    }
+}
diff --git a/Feature/Sources/IMAP/LoggingHandler.swift b/Feature/Sources/IMAP/LoggingHandler.swift
index 071fc092..752431b6 100644
--- a/Feature/Sources/IMAP/LoggingHandler.swift
+++ b/Feature/Sources/IMAP/LoggingHandler.swift
@@ -14,25 +14,20 @@ final class LoggingHandler: ChannelDuplexHandler, @unchecked Sendable {
     typealias OutboundIn = ByteBuffer
 
     func write(context: ChannelHandlerContext, data: NIOAny, promise: EventLoopPromise<Void>?) {
-        logger?.debug("\(self.unwrapOutboundIn(data).readableLogView(redactBase64Encoded: true))")
-        context.write(data, promise: promise)
+        logger?.debug("\(self.unwrapOutboundIn(data).stringValue)")
+        context.write(data, promise: promise)  // Handler only observes; pass unmodified data to next handler
     }
 
     func channelRead(context: ChannelHandlerContext, data: NIOAny) {
-        logger?.debug("\(self.unwrapInboundIn(data).readableLogView())")
-        context.fireChannelRead(data)
+        logger?.debug("\(self.unwrapInboundIn(data).stringValue)")
+        context.fireChannelRead(data)  // Pass unmodified data to next handler
     }
 }
 
-extension ByteBuffer {
-    // Format bytes as debug description; optionally redact user names and passwords
-    func readableLogView(redactBase64Encoded: Bool = false) -> String {
+private extension ByteBuffer {
+    var stringValue: String {
         let string: String = String(decoding: readableBytesView, as: UTF8.self).trimmingCharacters(in: .whitespacesAndNewlines)
-        guard let data: Data = Data(base64Encoded: string),
-            let string: String = String(data: data, encoding: .utf8)
-        else {
-            return string  // String not base64-encoded; return as is
-        }
-        return redactBase64Encoded ? "[redacted]" : string
+        // TODO: Redact IMAP credential
+        return string
     }
 }
diff --git a/Feature/Sources/IMAP/Message.swift b/Feature/Sources/IMAP/Message.swift
index c8955c10..a9d7932e 100644
--- a/Feature/Sources/IMAP/Message.swift
+++ b/Feature/Sources/IMAP/Message.swift
@@ -1,48 +1,45 @@
+import EmailAddress
 import Foundation
 import MIME
+import NIOIMAP
 
 /// [IMAP message attributes](https://www.ietf.org/rfc/rfc9051.html#section-2.3)
 public struct Message {
-    public enum Flag: String, CaseIterable, CustomStringConvertible, Sendable {
-        case seen = "\\Seen"
-        case answered = "\\Answered"
-        case flagged = "\\Flagged"
-        case deleted = "\\Deleted"
-        case draft = "\\Draft"
-        case forwarded = "$Forwarded"
-        case mdnSent = "$MDNSent"
-        case junk = "$Junk"
-        case notJunk = "$NotJunk"
-        case phishing = "$Phishing"
+    public typealias Flag = NIOIMAPCore.Flag
 
-        // MARK: CustomStringConvertible
-        public var description: String { rawValue }
-    }
-
-    public let isDeleted: Bool
-    public let folderID: Int
-    public let uid: String
-    public let subject: String
-    public let date: Date
+    public let body: Body
+    public let contentType: ContentType
     public let flags: [Flag]
-    public let senderList: String
-    public let toList: String
-    public let ccList: String
-    public let bccList: String
-    public let replyToList: String
-    public let attachmentCount: Int
-    public let internalDate: Date
+    public let folderID: Int
+    public let inReplyTo: String?
     public let messageID: String
-    public let previewType: String
-    public let preview: String
-    public let mimeType: String
-    public let normalizedSubjectHash: Int
-    public let isEmpty: Bool
-    public let isRead: Bool
-    public let isFlagged: Bool
-    public let isAnswered: Bool
-    public let isForwarded: Bool
-    public let messagePartID: Int
-    public let encryptionType: String
-    public let isNewMessage: Bool
+    public let replyTo: String?
+    public let size: Int
+    public let subject: String
+    public let uid: UID
+
+    public var isAnswered: Bool { flags.isAnswered }
+    public var isDeleted: Bool { flags.isDeleted }
+    public var isDraft: Bool { flags.isDraft }
+    public var isEmpty: Bool { body.isEmpty }
+    public var isFlagged: Bool { flags.isFlagged }
+    public var isForwarded: Bool { flags.isForwarded }
+    public var isSeen: Bool { flags.isSeen }
+}
+
+extension Message.Flag: @retroactive CustomStringConvertible {
+
+    // MARK: CustomStringConvertible
+    public var description: String { debugDescription }
+}
+
+public typealias UID = NIOIMAP.UID
+
+private extension [Message.Flag] {
+    var isAnswered: Bool { contains(.answered) }
+    var isDeleted: Bool { contains(.deleted) }
+    var isDraft: Bool { contains(.draft) }
+    var isFlagged: Bool { contains(.flagged) }
+    var isForwarded: Bool { contains(.keyword(.forwarded)) }
+    var isSeen: Bool { contains(.seen) }
 }
diff --git a/Feature/Sources/IMAP/Server.swift b/Feature/Sources/IMAP/Server.swift
index b81aadef..7c2e7beb 100644
--- a/Feature/Sources/IMAP/Server.swift
+++ b/Feature/Sources/IMAP/Server.swift
@@ -7,11 +7,11 @@ public struct Server: Equatable, Sendable {
     public let port: Int
 
     public init(
-        _ connectionSecurity: ConnectionSecurity = .startTLS,
+        _ connectionSecurity: ConnectionSecurity = .tls,
         hostname: String,
         username: String,
         password: String,
-        port: Int = 143  // 993
+        port: Int = 993
     ) {
         self.connectionSecurity = connectionSecurity
         self.hostname = hostname
diff --git a/Feature/Sources/MIME/Body.swift b/Feature/Sources/MIME/Body.swift
index 60934d4c..625ef3f3 100644
--- a/Feature/Sources/MIME/Body.swift
+++ b/Feature/Sources/MIME/Body.swift
@@ -1,7 +1,7 @@
 import Foundation
 
 /// Multipart body element described in [RFC 2045](https://www.rfc-editor.org/rfc/rfc2045#section-2.6)
-public struct Body: CustomStringConvertible, RawRepresentable {
+public struct Body: CustomStringConvertible, RawRepresentable, Sendable {
     public let contentTransferEncoding: ContentTransferEncoding?
     public let contentType: ContentType  // Body encoding is always ASCII
     public let parts: [Part]
@@ -85,3 +85,16 @@ public struct Body: CustomStringConvertible, RawRepresentable {
         try? self.init(rawValue)
     }
 }
+
+extension Body {
+    public static var empty: Self {
+        try! Self(
+            parts: [
+                try! Part(data: "".data(using: .ascii)!, contentType: .text(.plain, .ascii))
+            ], contentType: .text(.plain, .ascii))
+    }
+
+    public var isEmpty: Bool {
+        parts.count == 1 && (String(data: parts[0].data, encoding: .ascii) ?? "").isEmpty
+    }
+}
diff --git a/Feature/Sources/MIME/CharacterSet.swift b/Feature/Sources/MIME/CharacterSet.swift
index f912fc1b..ed6a51e1 100644
--- a/Feature/Sources/MIME/CharacterSet.swift
+++ b/Feature/Sources/MIME/CharacterSet.swift
@@ -1,5 +1,3 @@
-import Foundation
-
 /// Character encoding described in [RFC 2045](https://www.rfc-editor.org/rfc/rfc2045#section-2.2)
 public struct CharacterSet: CustomStringConvertible, Equatable, RawRepresentable, Sendable {
     public static var ascii: Self { try! Self("US-ASCII") }  // Default character encoding
diff --git a/Feature/Sources/MIME/ContentTransferEncoding.swift b/Feature/Sources/MIME/ContentTransferEncoding.swift
index 9092d395..b16b917c 100644
--- a/Feature/Sources/MIME/ContentTransferEncoding.swift
+++ b/Feature/Sources/MIME/ContentTransferEncoding.swift
@@ -1,5 +1,5 @@
 /// Multipart email body must be ASCII in transfer. Parts encoded by this library use `base64` transfer encoding exclusively, but we expect to decode parts in any of the enumerated encodings, especially `quotedPrintable`.
-public enum ContentTransferEncoding: String, CaseIterable, CustomStringConvertible, RawRepresentable {
+public enum ContentTransferEncoding: String, CaseIterable, CustomStringConvertible, RawRepresentable, Sendable {
     case ascii = "7bit"
     case base64
     case binary
diff --git a/Feature/Sources/MIME/Part.swift b/Feature/Sources/MIME/Part.swift
index e15700d5..3fae66d4 100644
--- a/Feature/Sources/MIME/Part.swift
+++ b/Feature/Sources/MIME/Part.swift
@@ -1,7 +1,7 @@
 import Foundation
 
 /// MIME part described in [RFC 2045](https://www.rfc-editor.org/rfc/rfc2045#section-2.5)
-public struct Part: CustomStringConvertible, RawRepresentable {
+public struct Part: CustomStringConvertible, RawRepresentable, Sendable {
 
     /// Instruct mail client to display decoded body part inline, in message, or link as an attachment. Optionally include file name and other metadata for source file.
     public let contentDisposition: ContentDisposition?
diff --git a/Feature/Sources/MIME/String.swift b/Feature/Sources/MIME/String.swift
index 488e284a..ec1c3e44 100644
--- a/Feature/Sources/MIME/String.swift
+++ b/Feature/Sources/MIME/String.swift
@@ -83,8 +83,8 @@ extension String {
     }
 }
 
+public var crlf: String { .crlf }
+
 extension [Character] {
     static var quotes: Self { ["\"", "'"] }
 }
-
-var crlf: String { .crlf }
diff --git a/Feature/Sources/MIME/UUID.swift b/Feature/Sources/MIME/UUID.swift
index fa67b8ef..7cfa1287 100644
--- a/Feature/Sources/MIME/UUID.swift
+++ b/Feature/Sources/MIME/UUID.swift
@@ -6,7 +6,7 @@ extension UUID {
         try! Boundary("\(prefix?.ascii ?? "")\(uuidString(segments, separator: separator))\(suffix?.ascii ?? "")")
     }
 
-    func uuidString(_ segments: Int, separator: String = .separator) -> String {
+    public func uuidString(_ segments: Int, separator: String = .separator) -> String {
         uuidString
             .components(separatedBy: String.separator)
             .prefix(max(segments, 1))
diff --git a/Feature/Sources/SMTP/Email.swift b/Feature/Sources/SMTP/Email.swift
index 26b75352..f3bd2d49 100644
--- a/Feature/Sources/SMTP/Email.swift
+++ b/Feature/Sources/SMTP/Email.swift
@@ -1,34 +1,18 @@
 import EmailAddress
 import Foundation
 import MIME
-import UniformTypeIdentifiers
 
 /// ``SMTPClient`` sends `Email`.
 public struct Email: Identifiable, Sendable {
-    public struct Part {
-        public let data: Data
-        public let contentType: String
-    }
-
     public let sender: EmailAddress
     public let recipients: [EmailAddress]
     public let copied: [EmailAddress]
     public let blindCopied: [EmailAddress]
     public let subject: String
     public let date: Date
-    public let parts: [Data]
-
-    public var body: Data {
-        var data: Data = Data()
-        for part in parts {
-            data.append(line.data(using: .utf8)!)
-            data.append(part)
-        }
-        data.append(line.data(using: .utf8)!)
-        return data
-    }
+    public let body: Body
 
-    public var contentType: String { "text/plain; charset=\"UTF-8\"" }
+    public var contentType: MIME.ContentType { body.contentType }
 
     public var messageID: String {
         // Format: https://www.jwz.org/doc/mid.html
@@ -46,7 +30,7 @@ public struct Email: Identifiable, Sendable {
         blindCopied: [EmailAddress] = [],
         subject: String = "",
         date: Date = Date(),
-        body parts: [Data] = [],
+        body: Body = .empty,
         id: UUID = UUID()
     ) {
         self.sender = sender
@@ -55,26 +39,12 @@ public struct Email: Identifiable, Sendable {
         self.blindCopied = blindCopied
         self.subject = subject
         self.date = date
-        self.parts = parts
+        self.body = body
         self.id = id
     }
 
-    var iso8601Date: String { ISO8601DateFormatter().string(from: date) }
     var allRecipients: [EmailAddress] { recipients + copied + blindCopied }
-    var dataBoundary: String { "\(id.uuidString(4))_part" }
 
     // MARK: Identifiable
     public let id: UUID
 }
-
-extension UUID {
-    func uuidString(_ segments: Int) -> String {
-        uuidString.components(separatedBy: "-").prefix(max(segments, 0)).joined(separator: "-")
-    }
-}
-
-extension String {
-    static var line: Self { "\r\n" }
-}
-
-var line: String { .line }
diff --git a/Feature/Sources/SMTP/LoggingHandler.swift b/Feature/Sources/SMTP/LoggingHandler.swift
index 071fc092..3682c2de 100644
--- a/Feature/Sources/SMTP/LoggingHandler.swift
+++ b/Feature/Sources/SMTP/LoggingHandler.swift
@@ -14,25 +14,29 @@ final class LoggingHandler: ChannelDuplexHandler, @unchecked Sendable {
     typealias OutboundIn = ByteBuffer
 
     func write(context: ChannelHandlerContext, data: NIOAny, promise: EventLoopPromise<Void>?) {
-        logger?.debug("\(self.unwrapOutboundIn(data).readableLogView(redactBase64Encoded: true))")
-        context.write(data, promise: promise)
+        logger?.debug("\(self.unwrapOutboundIn(data).stringValue)")
+        context.write(data, promise: promise)  // Handler only observes; pass unmodified data to next handler
     }
 
     func channelRead(context: ChannelHandlerContext, data: NIOAny) {
-        logger?.debug("\(self.unwrapInboundIn(data).readableLogView())")
-        context.fireChannelRead(data)
+        logger?.debug("\(self.unwrapInboundIn(data).stringValue)")
+        context.fireChannelRead(data)  // Pass unmodified data to next handler
     }
 }
 
 extension ByteBuffer {
-    // Format bytes as debug description; optionally redact user names and passwords
-    func readableLogView(redactBase64Encoded: Bool = false) -> String {
+    var stringValue: String {
         let string: String = String(decoding: readableBytesView, as: UTF8.self).trimmingCharacters(in: .whitespacesAndNewlines)
+        // Deocde base64-encoded credentials
         guard let data: Data = Data(base64Encoded: string),
             let string: String = String(data: data, encoding: .utf8)
         else {
-            return string  // String not base64-encoded; return as is
+            return string
         }
-        return redactBase64Encoded ? "[redacted]" : string
+        #if DEBUG
+        return string
+        #else
+        return String(repeating: "•", count: string.count)  // Redact decoded SMTP credential
+        #endif
     }
 }
diff --git a/Feature/Sources/SMTP/RequestEncoder.swift b/Feature/Sources/SMTP/RequestEncoder.swift
index 19ebbf7f..c533e71b 100644
--- a/Feature/Sources/SMTP/RequestEncoder.swift
+++ b/Feature/Sources/SMTP/RequestEncoder.swift
@@ -1,5 +1,6 @@
 import EmailAddress
 import Foundation
+import MIME
 import NIOCore
 
 enum Request {
@@ -37,18 +38,16 @@ struct RequestEncoder: MessageToByteEncoder {
         case .data:
             out.writeString("DATA")
         case .transferData(let email):
-            out.writeString("From: \(email.sender)\(line)")
-            out.writeString("To: \(email.recipients.map { $0.description }.joined(separator: " "))\(line)")
-            out.writeString("Date: \(email.iso8601Date)\(line)")  // "EEE, dd MMM yyyy HH:mm:ss Z"
-            out.writeString("Message-ID: \(email.messageID)\(line)")
-            out.writeString("Subject: \(email.subject)\(line)")
-            // out.writeString("MIME-Version: 1.0\(line)")
-            out.writeString("Content-Type: \(email.contentType)\(line)")
-            out.writeBytes(email.body)
-            out.writeString("\(line).")
+            out.writeString("From: \(email.sender)\(crlf)")
+            out.writeString("To: \(email.recipients.map { $0.description }.joined(separator: " "))\(crlf)")
+            out.writeString("Date: \(email.date.rfc822Format())\(crlf)")
+            out.writeString("Message-ID: \(email.messageID)\(crlf)")
+            out.writeString("Subject: \(email.subject)\(crlf)")
+            out.writeBytes(email.body.rawValue)
+            out.writeString("\(crlf).")
         case .quit:
             out.writeString("QUIT")
         }
-        out.writeString(line)
+        out.writeString(crlf)
     }
 }
diff --git a/Feature/Sources/SMTP/ResponseHandler.swift b/Feature/Sources/SMTP/ResponseHandler.swift
index ff4098b1..45875732 100644
--- a/Feature/Sources/SMTP/ResponseHandler.swift
+++ b/Feature/Sources/SMTP/ResponseHandler.swift
@@ -1,4 +1,3 @@
-import Foundation
 import NIOCore
 
 enum Response {
diff --git a/Feature/Sources/SMTP/SMTPClient.swift b/Feature/Sources/SMTP/SMTPClient.swift
index 6021fded..794d5ce5 100644
--- a/Feature/Sources/SMTP/SMTPClient.swift
+++ b/Feature/Sources/SMTP/SMTPClient.swift
@@ -12,7 +12,7 @@ public struct SMTPClient {
 
     public init(
         _ server: Server,
-        logger: Logger? = Logger(subsystem: "net.thunderbird.ios", category: "SMTP")
+        logger: Logger? = Logger(subsystem: "net.thunderbird", category: "SMTP")
     ) {
         group = NIOTSEventLoopGroup(loopCount: 1, defaultQoS: .utility)
         self.server = server
diff --git a/Feature/Sources/SMTP/SMTPError.swift b/Feature/Sources/SMTP/SMTPError.swift
index 50537d3d..3cb70a1c 100644
--- a/Feature/Sources/SMTP/SMTPError.swift
+++ b/Feature/Sources/SMTP/SMTPError.swift
@@ -1,5 +1,5 @@
 /// ``SMTPClient`` throws `SMTPError`.
-public enum SMTPError: Error {
+public enum SMTPError: Error, CustomStringConvertible, Equatable {
     case emailRecipientNotFound
     case remoteConnectionClosed
     case requiredTLSNotConfigured
@@ -9,4 +9,15 @@ public enum SMTPError: Error {
     init(_ error: Error) {
         self = error as? Self ?? .response(error.localizedDescription)
     }
+
+    // MARK: CustomStringConvertible
+    public var description: String {
+        switch self {
+        case .emailRecipientNotFound: "Email recipient not found"
+        case .remoteConnectionClosed: "Remote connection closed"
+        case .requiredTLSNotConfigured: "Required TLS not configured"
+        case .responseNotDecoded: "Response not decoded"
+        case .response(let string): "Response: \(string)"
+        }
+    }
 }
diff --git a/Feature/Tests/AutoconfigurationTests/DNSResolverTests.swift b/Feature/Tests/AutoconfigurationTests/DNSResolverTests.swift
index a8df037f..58ff31f5 100644
--- a/Feature/Tests/AutoconfigurationTests/DNSResolverTests.swift
+++ b/Feature/Tests/AutoconfigurationTests/DNSResolverTests.swift
@@ -19,7 +19,6 @@ struct DNSResolverTests {
     @Test func queryMX() async throws {
         let thunderbird: [MXRecord] = try await DNSResolver.queryMX("uname@thunderbird.net")
         #expect(thunderbird.count > 0)
-        print(thunderbird)
         let fastmail: [MXRecord] = try await DNSResolver.queryMX("user@fastmail.com")
         #expect(fastmail.count > 0)
         let google: [MXRecord] = try await DNSResolver.queryMX("user.name@gmail.com")
diff --git a/Feature/Tests/AutoconfigurationTests/FoundationTests/URLSessionTests.swift b/Feature/Tests/AutoconfigurationTests/FoundationTests/URLSessionTests.swift
index 3aeb06a2..82c87bca 100644
--- a/Feature/Tests/AutoconfigurationTests/FoundationTests/URLSessionTests.swift
+++ b/Feature/Tests/AutoconfigurationTests/FoundationTests/URLSessionTests.swift
@@ -114,6 +114,6 @@ extension URLSessionTests {
 
     @Test func suffixList() async throws {
         let suffixList: [String] = try await URLSession.shared.suffixList()
-        print(suffixList)
+        #expect(suffixList.count > 10000)
     }
 }
diff --git a/Feature/Tests/EmailAddressTests/EmailAddressTests.swift b/Feature/Tests/EmailAddressTests/EmailAddressTests.swift
index cc51dc1f..ddeae014 100644
--- a/Feature/Tests/EmailAddressTests/EmailAddressTests.swift
+++ b/Feature/Tests/EmailAddressTests/EmailAddressTests.swift
@@ -36,7 +36,6 @@ struct EmailAddressTests {
             "\"Example Name <name@example.com>\"".data(using: .utf8)!,
             "\"name@example.com\"".data(using: .utf8)!
         ]
-        print(try JSONDecoder().decode(EmailAddress.self, from: data[0]).value)
         #expect(try JSONDecoder().decode(EmailAddress.self, from: data[0]).value == "name@example.com")
         #expect(try JSONDecoder().decode(EmailAddress.self, from: data[0]).label == "Example Name")
         #expect(try JSONDecoder().decode(EmailAddress.self, from: data[1]).value == "name@example.com")
diff --git a/Feature/Tests/IMAPTests/IMAPClientTests.swift b/Feature/Tests/IMAPTests/IMAPClientTests.swift
new file mode 100644
index 00000000..55c4defa
--- /dev/null
+++ b/Feature/Tests/IMAPTests/IMAPClientTests.swift
@@ -0,0 +1,6 @@
+@testable import IMAP
+import Testing
+
+struct IMAPClientTests {
+
+}
diff --git a/Feature/Tests/IMAPTests/IMAPErrorTests.swift b/Feature/Tests/IMAPTests/IMAPErrorTests.swift
new file mode 100644
index 00000000..dc3eb9a8
--- /dev/null
+++ b/Feature/Tests/IMAPTests/IMAPErrorTests.swift
@@ -0,0 +1,10 @@
+@testable import IMAP
+import Testing
+
+struct IMAPErrorTests {
+
+    // MARK: CustomStringConvertible
+    @Test func description() {
+
+    }
+}
diff --git a/Feature/Tests/IMAPTests/LoggingHandlerTests.swift b/Feature/Tests/IMAPTests/LoggingHandlerTests.swift
index 872f5361..771790dd 100644
--- a/Feature/Tests/IMAPTests/LoggingHandlerTests.swift
+++ b/Feature/Tests/IMAPTests/LoggingHandlerTests.swift
@@ -1,13 +1,9 @@
-import Foundation
 import NIOCore
 @testable import IMAP
 import Testing
 
 struct ByteBufferTests {
-    @Test func readableSMTPView() {
-        #expect(ByteBuffer(string: "334 VXNlcm5hbWU6").readableLogView() == "334 VXNlcm5hbWU6")
-        #expect(ByteBuffer(string: "334 VXNlcm5hbWU6").readableLogView(redactBase64Encoded: true) == "334 VXNlcm5hbWU6")
-        #expect(ByteBuffer(string: "dXNlcm5hbWVAZXhhbXBsZS5jb20==").readableLogView() == "username@example.com")
-        #expect(ByteBuffer(string: "dXNlcm5hbWVAZXhhbXBsZS5jb20==").readableLogView(redactBase64Encoded: true) == "[redacted]")
+    @Test func stringValue() {
+
     }
 }
diff --git a/Feature/Tests/IMAPTests/MessageTests.swift b/Feature/Tests/IMAPTests/MessageTests.swift
new file mode 100644
index 00000000..32fb7b4c
--- /dev/null
+++ b/Feature/Tests/IMAPTests/MessageTests.swift
@@ -0,0 +1,23 @@
+import Foundation
+@testable import IMAP
+import Testing
+
+struct MessageTests {
+
+}
+
+extension MessageTests {
+    struct FlagTests {
+
+        // MARK: CustomStringConvertible
+        @Test func description() {
+            #expect(Message.Flag.answered.description == "\\Answered")
+            #expect(Message.Flag.deleted.description == "\\Deleted")
+            #expect(Message.Flag.draft.description == "\\Draft")
+            #expect(Message.Flag.flagged.description == "\\Flagged")
+            #expect(Message.Flag.seen.description == "\\Seen")
+            #expect(Message.Flag.extension("\\Example").description == "\\Example")
+            #expect(Message.Flag.keyword(.junk).description == "$Junk")
+        }
+    }
+}
diff --git a/Feature/Tests/MIMETests/BodyTests.swift b/Feature/Tests/MIMETests/BodyTests.swift
index 6342dfba..ea567feb 100644
--- a/Feature/Tests/MIMETests/BodyTests.swift
+++ b/Feature/Tests/MIMETests/BodyTests.swift
@@ -59,6 +59,22 @@ struct BodyTests {
     }
 }
 
+extension BodyTests {
+    @Test func empty() {
+        #expect(Body.empty.parts.first?.data == "".data(using: .ascii)!)
+        #expect(Body.empty.parts.first?.contentType == .text(.plain, .ascii))
+        #expect(Body.empty.contentType == .text(.plain, .ascii))
+    }
+
+    @Test func isEmpty() throws {
+        #expect(try Body(.fastmail).isEmpty == false)
+        #expect(try Body(.icloud).isEmpty == false)
+        #expect(try Body(.outlook).isEmpty == false)
+        #expect(try Body(.posteo).isEmpty == false)
+        #expect(Body.empty.isEmpty == true)
+    }
+}
+
 private extension Data {
     static var fastmail: Self { try! Bundle.module.data(forResource: "mime-body-fastmail.eml") }
     static var icloud: Self { try! Bundle.module.data(forResource: "mime-body-icloud.eml") }
diff --git a/Feature/Tests/SMTPTests/EmailTests.swift b/Feature/Tests/SMTPTests/EmailTests.swift
index 95f70d1e..00dfcd6c 100644
--- a/Feature/Tests/SMTPTests/EmailTests.swift
+++ b/Feature/Tests/SMTPTests/EmailTests.swift
@@ -1,14 +1,11 @@
 import Foundation
+import MIME
 @testable import SMTP
 import Testing
 
 struct EmailTests {
-    @Test func body() {
-        #expect(String(data: Email.email.body, encoding: .utf8) == emailBody.replacingOccurrences(of: "\n", with: "\r\n"))
-    }
-
     @Test func contentType() {
-        #expect(Email.email.contentType == "text/plain; charset=\"UTF-8\"")
+        #expect(Email.example.contentType == .text(.plain, .ascii))
     }
 
     @Test func messageID() {
@@ -18,13 +15,9 @@ struct EmailTests {
         #expect(Email(sender: "abc@", date: date, id: id).messageID == "<1762463150.A51D5B17>")
     }
 
-    @Test func iso8601Date() {
-        #expect(Email.email.iso8601Date == "2025-11-06T21:05:50Z")
-    }
-
     @Test func allRecipients() {
         #expect(
-            Email.email.allRecipients == [
+            Email.example.allRecipients == [
                 "recipient@example.com",
                 "no.name@exmaple.com",
                 "cc@example.com",
@@ -32,34 +25,10 @@ struct EmailTests {
             ]
         )
     }
-
-    @Test func dataBoundary() {
-        #expect(Email.email.dataBoundary == "A51D5B17-CA61-4FF1-A4A8_part")
-    }
-}
-
-struct UUIDTests {
-    @Test func uuidString() {
-        #expect(Email.email.id.uuidString == "A51D5B17-CA61-4FF1-A4A8-C717289B8F9E")
-        #expect(Email.email.id.uuidString(-2) == "")
-        #expect(Email.email.id.uuidString(0) == "")
-        #expect(Email.email.id.uuidString(1) == "A51D5B17")
-        #expect(Email.email.id.uuidString(2) == "A51D5B17-CA61")
-        #expect(Email.email.id.uuidString(3) == "A51D5B17-CA61-4FF1")
-        #expect(Email.email.id.uuidString(4) == "A51D5B17-CA61-4FF1-A4A8")
-        #expect(Email.email.id.uuidString(5) == "A51D5B17-CA61-4FF1-A4A8-C717289B8F9E")
-        #expect(Email.email.id.uuidString(99) == "A51D5B17-CA61-4FF1-A4A8-C717289B8F9E")
-    }
-}
-
-struct StringTests {
-    @Test func line() {
-        #expect(String.line == "\r\n")
-    }
 }
 
-private extension Email {
-    static var email: Self {
+extension Email {
+    static var example: Self {
         Self(
             sender: "Sender Name <sender@example.com>",
             recipients: [
@@ -74,17 +43,8 @@ private extension Email {
             ],
             subject: "Example email subject",
             date: Date(timeIntervalSince1970: 1762463150.82521),
-            body: [
-                "Body content parts can be plain text for now ;)".data(using: .utf8)!
-            ],
+            body: try! Body("Content-Type: text/plain; charset=\"US-ASCII\"\(crlf)\(crlf)Plain text body content (using only US-ASCII characters)\(crlf)"),
             id: UUID(uuidString: "A51D5B17-CA61-4FF1-A4A8-C717289B8F9E")!
         )
     }
 }
-
-// swift-format-ignore
-private let emailBody: String = """
-
-Body content parts can be plain text for now ;)
-
-"""
diff --git a/Feature/Tests/SMTPTests/LoggingHandlerTests.swift b/Feature/Tests/SMTPTests/LoggingHandlerTests.swift
index 0be71ccf..16c0e8cb 100644
--- a/Feature/Tests/SMTPTests/LoggingHandlerTests.swift
+++ b/Feature/Tests/SMTPTests/LoggingHandlerTests.swift
@@ -1,13 +1,10 @@
-import Foundation
 import NIOCore
 @testable import SMTP
 import Testing
 
 struct ByteBufferTests {
-    @Test func readableSMTPView() {
-        #expect(ByteBuffer(string: "334 VXNlcm5hbWU6").readableLogView() == "334 VXNlcm5hbWU6")
-        #expect(ByteBuffer(string: "334 VXNlcm5hbWU6").readableLogView(redactBase64Encoded: true) == "334 VXNlcm5hbWU6")
-        #expect(ByteBuffer(string: "dXNlcm5hbWVAZXhhbXBsZS5jb20==").readableLogView() == "username@example.com")
-        #expect(ByteBuffer(string: "dXNlcm5hbWVAZXhhbXBsZS5jb20==").readableLogView(redactBase64Encoded: true) == "[redacted]")
+    @Test func stringValue() {
+        #expect(ByteBuffer(string: "334 VXNlcm5hbWU6").stringValue == "334 VXNlcm5hbWU6")
+        #expect(ByteBuffer(string: "dXNlcm5hbWVAZXhhbXBsZS5jb20==").stringValue == "username@example.com")
     }
 }
diff --git a/Feature/Tests/SMTPTests/RequestTests.swift b/Feature/Tests/SMTPTests/RequestEncoderTests.swift
similarity index 62%
rename from Feature/Tests/SMTPTests/RequestTests.swift
rename to Feature/Tests/SMTPTests/RequestEncoderTests.swift
index d7f4e67e..0039d0ab 100644
--- a/Feature/Tests/SMTPTests/RequestTests.swift
+++ b/Feature/Tests/SMTPTests/RequestEncoderTests.swift
@@ -1,4 +1,4 @@
-import Foundation
+import MIME
 import NIOCore
 @testable import SMTP
 import Testing
@@ -22,41 +22,24 @@ struct RequestEncoderTests {
         #expect(buffer.readString(length: buffer.readableBytes) == "RCPT TO:<recipient@example.com>\r\n")
         try RequestEncoder().encode(data: .data, out: &buffer)
         #expect(buffer.readString(length: buffer.readableBytes) == "DATA\r\n")
-        try RequestEncoder().encode(data: .transferData(.email), out: &buffer)
-        #expect(buffer.readString(length: buffer.readableBytes) == "\(emailBody.replacingOccurrences(of: "\n", with: "\r\n"))\r\n")
+        try RequestEncoder().encode(data: .transferData(.example), out: &buffer)
+        #expect(buffer.readString(length: buffer.readableBytes) == example)
         try RequestEncoder().encode(data: .quit, out: &buffer)
         #expect(buffer.readString(length: buffer.readableBytes) == "QUIT\r\n")
     }
 }
 
-private extension Email {
-    static var email: Self {
-        Self(
-            sender: "Sender Name <sender@example.com>",
-            recipients: [
-                "Recipient Name <recipient@example.com>",
-                "no.name@exmaple.com"
-            ],
-            subject: "Example email subject",
-            date: Date(timeIntervalSince1970: 1762463150.82521),
-            body: [
-                "Body content parts can be plain text for now ;)".data(using: .utf8)!
-            ],
-            id: UUID(uuidString: "A51D5B17-CA61-4FF1-A4A8-C717289B8F9E")!
-        )
-    }
-}
-
 // swift-format-ignore
-private let emailBody: String = """
-From: Sender Name <sender@example.com>
-To: Recipient Name <recipient@example.com> no.name@exmaple.com
-Date: 2025-11-06T21:05:50Z
-Message-ID: <1762463150.A51D5B17@example.com>
-Subject: Example email subject
-Content-Type: text/plain; charset="UTF-8"
-
-Body content parts can be plain text for now ;)
+private let example: String = """
+From: Sender Name <sender@example.com>\r
+To: Recipient Name <recipient@example.com> no.name@exmaple.com\r
+Date: Thu, 06 Nov 2025 21:05:50 +0000\r
+Message-ID: <1762463150.A51D5B17@example.com>\r
+Subject: Example email subject\r
+Content-Type: text/plain; charset="US-ASCII"\r
+\r
+Plain text body content (using only US-ASCII characters)\r
+\r
+.\r
 
-.
 """
diff --git a/Feature/Tests/SMTPTests/SMTPClientTests.swift b/Feature/Tests/SMTPTests/SMTPClientTests.swift
index 9c880eaf..b9e2a7a8 100644
--- a/Feature/Tests/SMTPTests/SMTPClientTests.swift
+++ b/Feature/Tests/SMTPTests/SMTPClientTests.swift
@@ -1,38 +1,29 @@
 import Foundation
+import MIME
 @testable import SMTP
 import Testing
 
 struct SMTPClientTests {
     @Test(.disabled(if: Server.server.password.isEmpty)) func send() async throws {
-        let client: SMTPClient = SMTPClient(.server)
-        do {
-            try await client.send(.email)
-        } catch {
-            print(error)
-        }
+        try await SMTPClient(.server).send(.email)
     }
 
     @Test(.disabled(if: Server.server.password.isEmpty)) func sendToRecipient() async throws {
-        let client: SMTPClient = SMTPClient(.server)
-        do {
-            try await client.send(.email, to: "")
-        } catch {
-            print(error)
-        }
+        try await SMTPClient(.server).send(.email, to: "recipient@example.com")
     }
 }
 
 private extension Email {
     static var email: Self {
         Self(
-            sender: "",
+            sender: "sender@example.com",
             recipients: [
-                ""
+                "recipient@example.com"
             ],
             subject: "Example email subject",
-            body: [
-                "Body content parts can be plain text for now ;)".data(using: .utf8)!
-            ],
+            body: try! Body(parts: [
+                Part(data: "For a brief period of time, email body contents were made of plain, ASCII text only :)".data(using: .ascii)!, contentType: .text(.plain, .ascii))
+            ]),
             id: UUID(uuidString: "A51D5B17-CA61-4FF1-A4A8-C717289B8F9E")!
         )
     }
diff --git a/Feature/Tests/SMTPTests/SMTPErrorTests.swift b/Feature/Tests/SMTPTests/SMTPErrorTests.swift
new file mode 100644
index 00000000..b3818341
--- /dev/null
+++ b/Feature/Tests/SMTPTests/SMTPErrorTests.swift
@@ -0,0 +1,10 @@
+@testable import SMTP
+import Testing
+
+struct SMTPErrorTests {
+
+    // MARK: CustomStringConvertible
+    @Test func description() {
+        #expect(SMTPError.response("failure-description").description == "Response: failure-description")
+    }
+}