diff --git a/src/net/torvald/terrarum/App.java b/src/net/torvald/terrarum/App.java
index b54f165d5..b918a4db0 100644
--- a/src/net/torvald/terrarum/App.java
+++ b/src/net/torvald/terrarum/App.java
@@ -64,8 +64,11 @@ public class App implements ApplicationListener {
     public static final String VERSION_TAG = TerrarumAppConfiguration.VERSION_TAG;
 
     public static final String getVERSION_STRING() {
+
+        var snap = TerrarumAppConfiguration.INSTANCE.getVERSION_SNAPSHOT();
+
         return String.format("%d.%d.%d", VERSION_RAW >>> 48, (VERSION_RAW & 0xffff000000L) >>> 24, VERSION_RAW & 0xffffffL) +
-                (VERSION_TAG.isBlank() ? "" : "-"+VERSION_TAG);
+                (VERSION_TAG.isBlank() ? "" : "-"+VERSION_TAG) + (snap == null ? "" : (" (" + snap + ")"));
     }
 
     /**
diff --git a/src/net/torvald/terrarum/TerrarumAppConfiguration.kt b/src/net/torvald/terrarum/TerrarumAppConfiguration.kt
index e04b246fc..2ddae38ec 100644
--- a/src/net/torvald/terrarum/TerrarumAppConfiguration.kt
+++ b/src/net/torvald/terrarum/TerrarumAppConfiguration.kt
@@ -1,6 +1,8 @@
 package net.torvald.terrarum
 
 import net.torvald.terrarum.langpack.Lang
+import net.torvald.terrarum.serialise.toUint
+import java.util.*
 
 /**
  * You directly modify the source code to tune the engine to suit your needs.
@@ -68,6 +70,8 @@ basegame
     // Commit counts up to the Release 0.3.2: 2732
     // Commit counts up to the Release 0.3.3: ????
 
+    val VERSION_SNAPSHOT = if (App.IS_DEVELOPMENT_BUILD) Snapshot(0) else null
+
     const val VERSION_TAG: String = ""
 
     //////////////////////////////////////////////////////////
@@ -77,4 +81,35 @@ basegame
     const val TILE_SIZE = 16
     const val TILE_SIZEF = TILE_SIZE.toFloat()
     const val TILE_SIZED = TILE_SIZE.toDouble()
+}
+
+data class Snapshot(var revision: Int) {
+    private var today = Calendar.getInstance();
+    private var year = today.get(Calendar.YEAR) - 2000
+    private var week = today.get(Calendar.WEEK_OF_YEAR)
+
+    private var string = ""
+    private var bytes = byteArrayOf()
+
+    private fun update() {
+        string = "${year}w${week}${Char(0x61 + revision)}"
+        bytes = byteArrayOf(
+            revision.and(4).shl(7).or(year.and(127)).toByte(),
+            week.shl(2).or(revision.and(3)).toByte()
+        )
+    }
+
+    init {
+        update()
+    }
+
+    override fun toString() = string
+    fun toBytes() = bytes
+
+    constructor(b: ByteArray) : this(0) {
+        year = b[0].toUint() and 127
+        week = b[1].toUint() ushr 2
+        revision = (b[0].toUint() ushr 7 shl 2) or b[1].toUint().and(3)
+        update()
+    }
 }
\ No newline at end of file
diff --git a/src/net/torvald/terrarum/modulebasegame/serialise/PlayerSavingThread.kt b/src/net/torvald/terrarum/modulebasegame/serialise/PlayerSavingThread.kt
index 57e9c57b1..14aff08e8 100644
--- a/src/net/torvald/terrarum/modulebasegame/serialise/PlayerSavingThread.kt
+++ b/src/net/torvald/terrarum/modulebasegame/serialise/PlayerSavingThread.kt
@@ -2,6 +2,7 @@ package net.torvald.terrarum.modulebasegame.serialise
 
 import net.torvald.gdx.graphics.PixmapIO2
 import net.torvald.terrarum.App
+import net.torvald.terrarum.TerrarumAppConfiguration
 import net.torvald.terrarum.modulebasegame.IngameRenderer
 import net.torvald.terrarum.modulebasegame.TerrarumIngame
 import net.torvald.terrarum.savegame.*
@@ -41,6 +42,7 @@ class PlayerSavingThread(
         disk.saveKind = VDSaveKind.PLAYER_DATA
         disk.saveOrigin = disk.saveOrigin and 15 // remove flag "imported" if applicable
         disk.capacity = 0L
+        disk.snapshot = TerrarumAppConfiguration.VERSION_SNAPSHOT
 
         WriteSavegame.saveProgress = 0f
 
diff --git a/src/net/torvald/terrarum/modulebasegame/serialise/QuickSaveThread.kt b/src/net/torvald/terrarum/modulebasegame/serialise/QuickSaveThread.kt
index 455c9447e..1fbae8a24 100644
--- a/src/net/torvald/terrarum/modulebasegame/serialise/QuickSaveThread.kt
+++ b/src/net/torvald/terrarum/modulebasegame/serialise/QuickSaveThread.kt
@@ -2,6 +2,7 @@ package net.torvald.terrarum.modulebasegame.serialise
 
 import net.torvald.gdx.graphics.PixmapIO2
 import net.torvald.terrarum.App.printdbg
+import net.torvald.terrarum.TerrarumAppConfiguration
 import net.torvald.terrarum.modulebasegame.IngameRenderer
 import net.torvald.terrarum.modulebasegame.TerrarumIngame
 import net.torvald.terrarum.modulebasegame.gameactors.IngamePlayer
@@ -150,6 +151,7 @@ class QuickSingleplayerWorldSavingThread(
         skimmer.injectDiskCRC(disk.hashCode())
         skimmer.setSaveMode(1 + 2 * isAuto.toInt())
         skimmer.setSaveKind(VDSaveKind.WORLD_DATA)
+        skimmer.setSaveSnapshotVersion(TerrarumAppConfiguration.VERSION_SNAPSHOT)
         skimmer.setSaveOrigin(skimmer.getSaveOrigin() and 15) // remove flag "imported" if applicable
         skimmer.setLastModifiedTime(time_t)
         skimmer.setCreationTime(creation_t)
diff --git a/src/net/torvald/terrarum/modulebasegame/serialise/WorldSavingThread.kt b/src/net/torvald/terrarum/modulebasegame/serialise/WorldSavingThread.kt
index 090aa711c..13e086fda 100644
--- a/src/net/torvald/terrarum/modulebasegame/serialise/WorldSavingThread.kt
+++ b/src/net/torvald/terrarum/modulebasegame/serialise/WorldSavingThread.kt
@@ -42,6 +42,7 @@ class WorldSavingThread(
         disk.saveMode = 2 * isAuto.toInt() // no quick
         disk.saveKind = VDSaveKind.WORLD_DATA
         disk.saveOrigin = disk.saveOrigin and 15 // remove flag "imported" if applicable
+        disk.snapshot = TerrarumAppConfiguration.VERSION_SNAPSHOT
 
         // wait for screencap
         var emergencyStopCnt = 0
diff --git a/src/net/torvald/terrarum/modulebasegame/ui/UILoadDemoSavefiles.kt b/src/net/torvald/terrarum/modulebasegame/ui/UILoadDemoSavefiles.kt
index b34f13ce5..08fd2f978 100644
--- a/src/net/torvald/terrarum/modulebasegame/ui/UILoadDemoSavefiles.kt
+++ b/src/net/torvald/terrarum/modulebasegame/ui/UILoadDemoSavefiles.kt
@@ -526,14 +526,18 @@ class UIItemPlayerCells(
         loadable.rebuild()
         loadable.getFile(SAVEGAMEINFO)?.bytes?.let {
             var lastPlayTime0 = 0L
+            var genver = ""
 
             JsonFetcher.readFromJsonString(ByteArray64Reader(it, Common.CHARSET)).forEachSiblings { name, value ->
                 if (name == "worldCurrentlyPlaying") worldUUID = UUID.fromString(value.asString())
                 if (name == "totalPlayTime") totalPlayTime = parseDuration(value.asLong())
                 if (name == "lastPlayTime") lastPlayTime0 = value.asLong()
-                if (name == "genver") versionString = value.asLong().let { "${it.ushr(48)}.${it.ushr(24).and(0xFFFFFF)}.${it.and(0xFFFFFF)}" }
+                if (name == "genver") genver = value.asLong().let { "${it.ushr(48)}.${it.ushr(24).and(0xFFFFFF)}.${it.and(0xFFFFFF)}" }
             }
 
+            val snap = loadable.getSaveSnapshotVersion()
+            versionString = genver + (if (snap != null) "-$snap" else "")
+
             App.savegamePlayersName[playerUUID]?.let { if (it.isNotBlank()) playerName = it else "(name)" }
             App.savegameWorldsName[worldUUID]?.let { if (it.isNotBlank()) worldName = it }
             lastPlayTime = Instant.ofEpochSecond(lastPlayTime0)
@@ -749,6 +753,7 @@ class UIItemWorldCells(
     private val metaFile: EntryFile?
     private val saveName: String
     private val saveMode: Int
+    private val snapshot: String
     private val isQuick: Boolean
     private val isAuto: Boolean
     private var saveDamaged: Boolean = false
@@ -760,6 +765,7 @@ class UIItemWorldCells(
 
         saveName = skimmer.getDiskName(Common.CHARSET)
         saveMode = skimmer.getSaveMode()
+        snapshot = skimmer.getSaveSnapshotVersion()?.toString() ?: ""
         isQuick = (saveMode % 2 == 1)
         isAuto = (saveMode.ushr(1) != 0)
 
diff --git a/src/net/torvald/terrarum/modulebasegame/ui/UILoadManage.kt b/src/net/torvald/terrarum/modulebasegame/ui/UILoadManage.kt
index 2a7ae7d3b..4786ef8bf 100644
--- a/src/net/torvald/terrarum/modulebasegame/ui/UILoadManage.kt
+++ b/src/net/torvald/terrarum/modulebasegame/ui/UILoadManage.kt
@@ -447,12 +447,16 @@ class UILoadManage(val full: UILoadSavegame) : UICanvas() {
         if (!this.initialised) this.rebuild()
         this.getFile(SAVEGAMEINFO)!!.bytes.let {
             var lastPlayTime = 0L
-            var versionString = ""
+            var genver = ""
             val isAuto = (this.getSaveMode() and 0b10 != 0)
             JsonFetcher.readFromJsonString(ByteArray64Reader(it, Common.CHARSET)).forEachSiblings { name, value ->
                 if (name == "lastPlayTime") lastPlayTime = value.asLong()
-                if (name == "genver") versionString = value.asLong().let { "${it.ushr(48)}.${it.ushr(24).and(0xFFFFFF)}.${it.and(0xFFFFFF)}" }
+                if (name == "genver") genver = value.asLong().let { "${it.ushr(48)}.${it.ushr(24).and(0xFFFFFF)}.${it.and(0xFFFFFF)}" }
             }
+            val snap = this.getSaveSnapshotVersion()?.toString()
+
+//            val versionString = genver + (if (snap != null) "-$snap" else "")
+            val versionString = if (snap != null) "$snap" else genver
 
             return SavegameMeta(
                 lastPlayTime,
diff --git a/src/net/torvald/terrarum/modulebasegame/ui/UINewCharacter.kt b/src/net/torvald/terrarum/modulebasegame/ui/UINewCharacter.kt
index 840aad85a..6ab18a835 100644
--- a/src/net/torvald/terrarum/modulebasegame/ui/UINewCharacter.kt
+++ b/src/net/torvald/terrarum/modulebasegame/ui/UINewCharacter.kt
@@ -80,6 +80,7 @@ class UINewCharacter(val remoCon: UIRemoCon) : UICanvas() {
                 disk.saveMode = 2 // auto, no quick
                 disk.capacity = 0L
                 disk.saveOrigin = VDSaveOrigin.INGAME
+                disk.snapshot = TerrarumAppConfiguration.VERSION_SNAPSHOT
 
                 WritePlayer(player, disk, null, time_t)
                 VDUtil.dumpToRealMachine(disk, outFile)
diff --git a/src/net/torvald/terrarum/savegame/DiskSkimmer.kt b/src/net/torvald/terrarum/savegame/DiskSkimmer.kt
index 57ec8fd0a..0020e71e3 100644
--- a/src/net/torvald/terrarum/savegame/DiskSkimmer.kt
+++ b/src/net/torvald/terrarum/savegame/DiskSkimmer.kt
@@ -1,6 +1,7 @@
 package net.torvald.terrarum.savegame
 
 import net.torvald.terrarum.App.printdbg
+import net.torvald.terrarum.Snapshot
 import net.torvald.terrarum.serialise.toUint
 import net.torvald.terrarum.serialise.toUlong
 import java.io.*
@@ -389,6 +390,16 @@ removefile:
         fa.close()
     }
 
+    fun setSaveSnapshotVersion(snapshot: Snapshot?) {
+        val fa = RandomAccessFile(diskFile, "rwd")
+        fa.seek(51L)
+        if (snapshot == null)
+            fa.write(byteArrayOf(0, 0))
+        else
+            fa.write(snapshot.toBytes())
+        fa.close()
+    }
+
     /**
      * @return Save type (0b 0000 00ab)
      *                   b: unset - full save; set - quicksave (only applicable to worlds -- quicksave just means the disk is in dirty state)
@@ -418,6 +429,17 @@ removefile:
         return fa.read().also { fa.close() }
     }
 
+    fun getSaveSnapshotVersion(): Snapshot? {
+        val fa = RandomAccessFile(diskFile, "rwd")
+        fa.seek(52L)
+
+        val b1 = fa.read().toByte()
+        val b2 = fa.read().toByte().also { fa.close() }
+
+        return if (b1 == b2 && b1 == 0.toByte()) null
+        else Snapshot(byteArrayOf(b1, b2))
+    }
+
 
 
     override fun getDiskName(charset: Charset): String {
diff --git a/src/net/torvald/terrarum/savegame/VirtualDisk.kt b/src/net/torvald/terrarum/savegame/VirtualDisk.kt
index ddd9e383b..5234bab4e 100644
--- a/src/net/torvald/terrarum/savegame/VirtualDisk.kt
+++ b/src/net/torvald/terrarum/savegame/VirtualDisk.kt
@@ -1,6 +1,7 @@
 package net.torvald.terrarum.savegame
 
 import net.torvald.terrarum.App.printdbg
+import net.torvald.terrarum.Snapshot
 import net.torvald.terrarum.savegame.VDSaveKind.PLAYER_DATA
 import net.torvald.terrarum.savegame.VDSaveKind.WORLD_DATA
 import net.torvald.terrarum.serialise.Common
@@ -79,7 +80,15 @@ Version 254 is a customised version of TEVD tailored to be used as a savegame fo
     Int8        Savefile Origin Flags (lower nybble: persistent, upper nybble: can be removed if conditions are met)
                   0: Created in-game
                  16: Imported (will be removed once the file is loaded by the player and saved in-game)
-    Int8[12]    Extra info bytes reserved for future usage
+    Int16       Snapshot Number
+                 0b A_yyyyyyy wwwwww_aa
+                 where:
+                   y: Current Year - 2000 (2023 -> 23)
+                   w: ISO Week Number (1-53)
+                   Aaa: Alphabet (a->000, b->001, ... e->100, f->101, ..., h->111)
+                 e.g. 23w40f is encoded as 1_0010111 101000_01
+    Int8[10]    Extra info bytes reserved for future usage
+
     -- END extraInfoBytes --
     UInt8[236]  Rest of the long disk name (268 bytes total)
 
@@ -156,6 +165,25 @@ class VirtualDisk(
     var saveOrigin: Int
         set(value) { extraInfoBytes[3] = value.toByte() }
         get() = extraInfoBytes[3].toUint()
+    var snapshot: Snapshot?
+        set(value) {
+            if (value == null) {
+                extraInfoBytes[4] = 0
+                extraInfoBytes[5] = 0
+            }
+            else {
+                value.toBytes().forEachIndexed { index, byte ->
+                    extraInfoBytes[4+index] = byte
+                }
+            }
+        }
+        get() {
+            return if (extraInfoBytes[4] == extraInfoBytes[5] && extraInfoBytes[4] == 0.toByte()) null
+            else {
+                Snapshot(extraInfoBytes.sliceArray(4..5))
+            }
+        }
+
     override fun getDiskName(charset: Charset) = diskName.toCanonicalString(charset)
     val root: DiskEntry
         get() = entries[0]!!
diff --git a/src/net/torvald/unsafe/UnsafePtr.kt b/src/net/torvald/unsafe/UnsafePtr.kt
index a3e127287..44858f755 100644
--- a/src/net/torvald/unsafe/UnsafePtr.kt
+++ b/src/net/torvald/unsafe/UnsafePtr.kt
@@ -113,8 +113,8 @@ internal class UnsafePtr(pointer: Long, allocSize: Long) {
         // appear (e.g. getting garbage values when it fucking shouldn't)
 
         // using ifs instead of assertions: inactive assert statements still slows down the app
-        if (destroyed) { throw DanglingPointerException("The pointer is already destroyed ($this)") }
-        if (index !in 0 until size) { throw AddressOverflowException("Index: $index; alloc size: $size") }
+//        if (destroyed) { throw DanglingPointerException("The pointer is already destroyed ($this)") }
+//        if (index !in 0 until size) { throw AddressOverflowException("Index: $index; alloc size: $size") }
     }
 
     operator fun get(index: Long): Byte {