LoopKit · marionbarker · Jul 20, 2026 · Jun 16, 2026 · Jun 21, 2026 · Jun 21, 2026
diff --git a/CGMBLEKit.xcodeproj/project.pbxproj b/CGMBLEKit.xcodeproj/project.pbxproj
@@ -60,6 +60,7 @@
 		438621CE2292074A00741DFE /* ShareClientUI.framework in Frameworks */ = {isa = PBXBuildFile; fileRef = 4325E9EE210EAF3F00969CE5 /* ShareClientUI.framework */; };
 		43880F981D9E19FC009061A8 /* TransmitterVersionRxMessage.swift in Sources */ = {isa = PBXBuildFile; fileRef = 43880F971D9E19FC009061A8 /* TransmitterVersionRxMessage.swift */; };
 		43880F9A1D9E1BD7009061A8 /* TransmitterVersionRxMessageTests.swift in Sources */ = {isa = PBXBuildFile; fileRef = 43880F991D9E1BD7009061A8 /* TransmitterVersionRxMessageTests.swift */; };
+		CA04000000000000000010C2 /* AnubisDetectionTests.swift in Sources */ = {isa = PBXBuildFile; fileRef = CA04000000000000000010C1 /* AnubisDetectionTests.swift */; };
 		43A8EC4A210D09BE00A81379 /* LoopKitUI.framework in Frameworks */ = {isa = PBXBuildFile; fileRef = 43A8EC49210D09BE00A81379 /* LoopKitUI.framework */; };
 		43A8EC4C210D09DA00A81379 /* LoopKitUI.framework in Frameworks */ = {isa = PBXBuildFile; fileRef = 43A8EC49210D09BE00A81379 /* LoopKitUI.framework */; };
 		43A8EC56210D0A7400A81379 /* CGMBLEKitUI.h in Headers */ = {isa = PBXBuildFile; fileRef = 43A8EC54210D0A7400A81379 /* CGMBLEKitUI.h */; settings = {ATTRIBUTES = (Public, ); }; };
@@ -391,6 +392,7 @@
 		43846AC71D8F89BE00799272 /* CalibrationDataRxMessageTests.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = CalibrationDataRxMessageTests.swift; sourceTree = "<group>"; };
 		43880F971D9E19FC009061A8 /* TransmitterVersionRxMessage.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = TransmitterVersionRxMessage.swift; sourceTree = "<group>"; };
 		43880F991D9E1BD7009061A8 /* TransmitterVersionRxMessageTests.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = TransmitterVersionRxMessageTests.swift; sourceTree = "<group>"; };
+		CA04000000000000000010C1 /* AnubisDetectionTests.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = AnubisDetectionTests.swift; sourceTree = "<group>"; };
 		43A8EC49210D09BE00A81379 /* LoopKitUI.framework */ = {isa = PBXFileReference; explicitFileType = wrapper.framework; path = LoopKitUI.framework; sourceTree = BUILT_PRODUCTS_DIR; };
 		43A8EC52210D0A7400A81379 /* CGMBLEKitUI.framework */ = {isa = PBXFileReference; explicitFileType = wrapper.framework; includeInIndex = 0; path = CGMBLEKitUI.framework; sourceTree = BUILT_PRODUCTS_DIR; };
 		43A8EC54210D0A7400A81379 /* CGMBLEKitUI.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = CGMBLEKitUI.h; sourceTree = "<group>"; };
@@ -730,6 +732,7 @@
 				43460F87200B30D10030C0E3 /* TransmitterIDTests.swift */,
 				43F82BCB1D035AA4006F5DD7 /* TransmitterTimeRxMessageTests.swift */,
 				43880F991D9E1BD7009061A8 /* TransmitterVersionRxMessageTests.swift */,
+				CA04000000000000000010C1 /* AnubisDetectionTests.swift */,
 			);
 			path = CGMBLEKitTests;
 			sourceTree = "<group>";
@@ -1281,6 +1284,7 @@
 				43F82BD21D037040006F5DD7 /* SessionStopRxMessageTests.swift in Sources */,
 				43E397911D5692080028E321 /* GlucoseTests.swift in Sources */,
 				43880F9A1D9E1BD7009061A8 /* TransmitterVersionRxMessageTests.swift in Sources */,
+				CA04000000000000000010C2 /* AnubisDetectionTests.swift in Sources */,
 				43DC87C21C8B520F005BC30D /* GlucoseRxMessageTests.swift in Sources */,
 			);
 			runOnlyForDeploymentPostprocessing = 0;

diff --git a/CGMBLEKit/Glucose.swift b/CGMBLEKit/Glucose.swift
@@ -52,7 +52,7 @@ public struct Glucose {
         if timeMessage.hasValidSensorSession {
             let sessionStartDate = activationDate.addingTimeInterval(TimeInterval(timeMessage.sessionStartTime))
             self.sessionStartDate = sessionStartDate
-            self.sessionExpDate = sessionStartDate.addingTimeInterval(10*24*60*60)
+            self.sessionExpDate = sessionStartDate.addingTimeInterval(.hours(24 * Double(TransmitterManagerState.defaultSensorLifeDays)))
         } else {
             sessionStartDate = nil
             sessionExpDate = nil
@@ -66,7 +66,7 @@ public struct Glucose {
     public let status: TransmitterStatus
     public let activationDate: Date
     public let sessionStartDate: Date?
-    public let sessionExpDate: Date?
+    public internal(set) var sessionExpDate: Date?
 
     public var hasValidSensorSession: Bool {
         return sessionStartDate != nil

diff --git a/CGMBLEKit/Messages/TransmitterVersionRxMessage.swift b/CGMBLEKit/Messages/TransmitterVersionRxMessage.swift
@@ -9,11 +9,13 @@
 import Foundation
 
 
-struct TransmitterVersionRxMessage: TransmitterRxMessage {
-    let status: UInt8
-    let firmwareVersion: [UInt8]
+public struct TransmitterVersionRxMessage: TransmitterRxMessage {
+    public let status: UInt8
+    public let firmwareVersion: [UInt8]
+    /// Lifetime the transmitter reports for itself (stock G6 = 90, Anubis-modded G6 = 180).
+    public let transmitterExpiryInDays: UInt16
 
-    init?(data: Data) {
+    public init?(data: Data) {
         guard data.count == 19 && data.isCRCValid else {
             return nil
         }
@@ -24,6 +26,12 @@ struct TransmitterVersionRxMessage: TransmitterRxMessage {
 
         status = data[1]
         firmwareVersion = data[2..<6].map { $0 }
+        transmitterExpiryInDays = (UInt16(data[14]) << 8) + UInt16(data[13])
     }
 
+    /// Heuristic borrowed from xDrip4iOS: Anubis-modded G6 transmitters
+    /// report a 180-day expiry in the version-rx frame; stock G6 reports 90.
+    public var isAnubis: Bool {
+        return transmitterExpiryInDays == 180
+    }
 }
diff --git a/CGMBLEKit/Messages/TransmitterVersionTxMessage.swift b/CGMBLEKit/Messages/TransmitterVersionTxMessage.swift
@@ -9,8 +9,10 @@
 import Foundation
 
 
-struct TransmitterVersionTxMessage {
+struct TransmitterVersionTxMessage: RespondableMessage {
     typealias Response = TransmitterVersionRxMessage
 
-    let opcode: Opcode = .transmitterVersionTx
+    var data: Data {
+        return Data(for: .transmitterVersionTx).appendingCRC()
+    }
 }
diff --git a/CGMBLEKit/Transmitter.swift b/CGMBLEKit/Transmitter.swift
@@ -22,6 +22,13 @@ public protocol TransmitterDelegate: AnyObject {
     func transmitter(_ transmitter: Transmitter, didReadBackfill glucose: [Glucose])
 
     func transmitter(_ transmitter: Transmitter, didReadUnknownData data: Data)
+
+    func transmitter(_ transmitter: Transmitter, didReadTransmitterVersion message: TransmitterVersionRxMessage)
+}
+
+public extension TransmitterDelegate {
+    // Default no-op so existing implementors don't need to opt in.
+    func transmitter(_ transmitter: Transmitter, didReadTransmitterVersion message: TransmitterVersionRxMessage) {}
 }
 
 /// These methods are called on a private background queue. It is the responsibility of the client to ensure thread-safety.
@@ -64,6 +71,8 @@ public final class Transmitter: BluetoothManagerDelegate {
 
     public var passiveModeEnabled: Bool
 
+    public var needsExpiryRead: Bool = false
+
     public weak var delegate: TransmitterDelegate?
 
     public weak var commandSource: TransmitterCommandSource?
@@ -206,6 +215,16 @@ public final class Transmitter: BluetoothManagerDelegate {
                     self.log.debug("Reading calibration data")
                     let calibrationMessage = try? peripheral.readCalibrationData()
 
+                    // Best-effort version read — surfaces transmitter-reported
+                    // expiry (Anubis detection). Optional: don't fail the
+                    // connect cycle if the transmitter doesn't answer.
+                    self.log.debug("Reading transmitter version")
+                    if let versionMessage = try? peripheral.readTransmitterVersion() {
+                        self.delegateQueue.async {
+                            self.delegate?.transmitter(self, didReadTransmitterVersion: versionMessage)
+                        }
+                    }
+
                     let glucose = Glucose(
                         transmitterID: self.id.id,
                         glucoseMessage: glucoseMessage,
@@ -267,6 +286,13 @@ public final class Transmitter: BluetoothManagerDelegate {
                         self.delegate?.transmitter(self, didError: error)
                     }
                 }
+
+                if self.needsExpiryRead, let versionMessage = try? peripheral.readTransmitterVersion() {
+                    self.needsExpiryRead = false
+                    self.delegateQueue.async {
+                        self.delegate?.transmitter(self, didReadTransmitterVersion: versionMessage)
+                    }
+                }
             }
         case .transmitterTimeRx?:
             if let timeMessage = TransmitterTimeRxMessage(data: response) {
@@ -338,6 +364,14 @@ public final class Transmitter: BluetoothManagerDelegate {
             }
 
             lastCalibrationMessage = calibrationDataMessage
+        case .transmitterVersionRx?:
+            guard let versionMessage = TransmitterVersionRxMessage(data: response) else {
+                break
+            }
+
+            delegateQueue.async {
+                self.delegate?.transmitter(self, didReadTransmitterVersion: versionMessage)
+            }
         case .none:
             delegateQueue.async {
                 self.delegate?.transmitter(self, didReadUnknownData: response)
@@ -551,6 +585,14 @@ fileprivate extension PeripheralManager {
         }
     }
 
+    func readTransmitterVersion() throws -> TransmitterVersionRxMessage {
+        do {
+            return try writeMessage(TransmitterVersionTxMessage(), for: .control)
+        } catch let error {
+            throw TransmitterError.controlError("Error getting transmitter version: \(error)")
+        }
+    }
+
     func disconnect() {
         do {
             try setNotifyValue(false, for: .control)

diff --git a/CGMBLEKit/TransmitterManager.swift b/CGMBLEKit/TransmitterManager.swift
@@ -81,6 +81,8 @@ public class TransmitterManager: TransmitterDelegate {
 
         self.transmitter.delegate = self
 
+        self.transmitter.needsExpiryRead = state.transmitterExpiryInDays == nil
+
         #if targetEnvironment(simulator)
         setupSimulatedSampleGenerator()
         #endif
@@ -270,6 +272,9 @@ public class TransmitterManager: TransmitterDelegate {
             "latestConnection: \(String(describing: latestConnection))",
             "dataIsFresh: \(dataIsFresh)",
             "providesBLEHeartbeat: \(providesBLEHeartbeat)",
+            "transmitterExpiryInDays: \(String(describing: state.transmitterExpiryInDays))",
+            "isAnubis: \(isAnubis)",
+            "sensorLifeDays: \(state.sensorLifeDays)",
             shareManager.debugDescription,
             "observers.count: \(observers.cleanupDeallocatedElements().count)",
             String(reflecting: transmitter),
@@ -310,6 +315,9 @@ public class TransmitterManager: TransmitterDelegate {
     }
 
     public func transmitter(_ transmitter: Transmitter, didRead glucose: Glucose) {
+        var glucose = glucose
+        glucose.sessionExpDate = glucose.sessionStartDate?.addingTimeInterval(state.sensorLife)
+
         guard glucose != latestReading else {
             updateDelegate(with: .noData)
             return
@@ -341,8 +349,8 @@ public class TransmitterManager: TransmitterDelegate {
                     date: sessionStartDate,
                     type: .sensorStart,
                     deviceIdentifier: transmitter.ID,
-                    expectedLifetime: .hours(24 * 10),
-                    warmupPeriod: .hours(2)
+                    expectedLifetime: state.sensorLife,
+                    warmupPeriod: state.isAnubis ? .minutes(50) : .hours(2)
                 ))
             } else {
                 log.error("Ignoring sensor start event with invalid session start time: %{public}@", String(describing: glucose))
@@ -431,6 +439,48 @@ public class TransmitterManager: TransmitterDelegate {
 
         logDeviceCommunication("Unknown sensor data: \(data.hexadecimalString)", type: .error)
     }
+
+    public func transmitter(_ transmitter: Transmitter, didReadTransmitterVersion message: TransmitterVersionRxMessage) {
+        log.default("Transmitter reports expiry of %d days (isAnubis=%@)",
+                    message.transmitterExpiryInDays, String(describing: message.isAnubis))
+        logDeviceCommunication("Transmitter version: expiry \(message.transmitterExpiryInDays) days", type: .receive)
+        transmitter.needsExpiryRead = false
+        mutateState { state in
+            state.transmitterExpiryInDays = message.transmitterExpiryInDays
+        }
+        updateLatestReadingSessionExpDate()
+    }
+
+    /// `true` once the transmitter has reported the Anubis 180-day lifetime.
+    public var isAnubis: Bool {
+        return state.isAnubis
+    }
+
+    /// User-configured session length; only honored for Anubis (see `sensorLife`).
+    public var sensorLifeDays: Int {
+        get {
+            return state.sensorLifeDays
+        }
+        set {
+            mutateState { state in
+                state.sensorLifeDays = TransmitterManagerState.clampedSensorLifeDays(newValue)
+            }
+            updateLatestReadingSessionExpDate()
+        }
+    }
+
+    public var sensorLife: TimeInterval {
+        return state.sensorLife
+    }
+
+    /// Re-stamps the cached reading so a sensor-life change applies immediately.
+    private func updateLatestReadingSessionExpDate() {
+        guard var reading = latestReading else {
+            return
+        }
+        reading.sessionExpDate = reading.sessionStartDate?.addingTimeInterval(state.sensorLife)
+        latestReading = reading
+    }
 }
 
 

diff --git a/CGMBLEKit/TransmitterManagerState.swift b/CGMBLEKit/TransmitterManagerState.swift
@@ -14,6 +14,15 @@ public struct TransmitterManagerState: RawRepresentable, Equatable {
 
     public static let version = 1
 
+    public static let defaultSensorLifeDays = 10
+
+    /// Selectable session lengths for Anubis-modded transmitters.
+    public static let sensorLifeDaysRange = 10...60
+
+    static func clampedSensorLifeDays(_ days: Int) -> Int {
+        return min(max(days, sensorLifeDaysRange.lowerBound), sensorLifeDaysRange.upperBound)
+    }
+
     public var transmitterID: String
 
     public var passiveModeEnabled: Bool = true
@@ -24,16 +33,27 @@ public struct TransmitterManagerState: RawRepresentable, Equatable {
 
     public var shouldSyncToRemoteService: Bool
 
+    /// Transmitter-reported lifetime in days (90 for stock G6, 180 for
+    /// Anubis-modded). `nil` until the first version-rx frame comes in.
+    public var transmitterExpiryInDays: UInt16?
+
+    /// User-configured session length; only honored for Anubis (see `sensorLife`).
+    public var sensorLifeDays: Int
+
     public init(
         transmitterID: String,
         shouldSyncToRemoteService: Bool = true,
         transmitterStartDate: Date? = nil,
-        sensorStartOffset: UInt32? = nil
+        sensorStartOffset: UInt32? = nil,
+        transmitterExpiryInDays: UInt16? = nil,
+        sensorLifeDays: Int = Self.defaultSensorLifeDays
     ) {
         self.transmitterID = transmitterID
         self.shouldSyncToRemoteService = shouldSyncToRemoteService
         self.transmitterStartDate = transmitterStartDate
         self.sensorStartOffset = sensorStartOffset
+        self.transmitterExpiryInDays = transmitterExpiryInDays
+        self.sensorLifeDays = Self.clampedSensorLifeDays(sensorLifeDays)
     }
 
     public init?(rawValue: RawValue) {
@@ -48,11 +68,18 @@ public struct TransmitterManagerState: RawRepresentable, Equatable {
 
         let sensorStartOffset = rawValue["sensorStartOffset"] as? UInt32
 
+        let transmitterExpiryInDays = (rawValue["transmitterExpiryInDays"] as? UInt16)
+            ?? (rawValue["transmitterExpiryInDays"] as? Int).map { UInt16($0) }
+
+        let sensorLifeDays = rawValue["sensorLifeDays"] as? Int ?? Self.defaultSensorLifeDays
+
         self.init(
             transmitterID: transmitterID,
             shouldSyncToRemoteService: shouldSyncToRemoteService,
             transmitterStartDate: transmitterStartDate,
-            sensorStartOffset: sensorStartOffset
+            sensorStartOffset: sensorStartOffset,
+            transmitterExpiryInDays: transmitterExpiryInDays,
+            sensorLifeDays: sensorLifeDays
         )
     }
 
@@ -64,7 +91,19 @@ public struct TransmitterManagerState: RawRepresentable, Equatable {
 
         rval["transmitterStartDate"] = transmitterStartDate
         rval["sensorStartOffset"] = sensorStartOffset
+        rval["transmitterExpiryInDays"] = transmitterExpiryInDays.map { Int($0) }
+        rval["sensorLifeDays"] = sensorLifeDays
 
         return rval
     }
+
+    /// `true` once the transmitter has reported the Anubis 180-day lifetime.
+    public var isAnubis: Bool {
+        return transmitterExpiryInDays == 180
+    }
+
+    /// Active session length: `sensorLifeDays` for Anubis, else the stock 10 days.
+    public var sensorLife: TimeInterval {
+        return .hours(24 * Double(isAnubis ? sensorLifeDays : Self.defaultSensorLifeDays))
+    }
 }