diff --git a/tests/waku_store_sync/sync_utils.nim b/tests/waku_store_sync/sync_utils.nim
new file mode 100644
index 000000000..b949b89bf
--- /dev/null
+++ b/tests/waku_store_sync/sync_utils.nim
@@ -0,0 +1,60 @@
+{.used.}
+
+import std/[options, random], chronos, chronicles
+
+import waku/[node/peer_manager, waku_core, waku_store_sync], ../testlib/wakucore
+
+randomize()
+
+proc randomHash*(rng: var Rand): WakuMessageHash =
+  var hash = EmptyWakuMessageHash
+
+  for i in 0 ..< hash.len:
+    hash[i] = rng.rand(uint8)
+
+  return hash
+
+proc newTestWakuRecon*(
+    switch: Switch,
+    idsRx: AsyncQueue[ID],
+    wantsTx: AsyncQueue[(PeerId, Fingerprint)],
+    needsTx: AsyncQueue[(PeerId, Fingerprint)],
+): Future[SyncReconciliation] {.async.} =
+  let peerManager = PeerManager.new(switch)
+
+  let res = await SyncReconciliation.new(
+    peerManager = peerManager,
+    wakuArchive = nil,
+    relayJitter = 0.seconds,
+    idsRx = idsRx,
+    wantsTx = wantsTx,
+    needsTx = needsTx,
+  )
+
+  let proto = res.get()
+
+  proto.start()
+  switch.mount(proto)
+
+  return proto
+
+proc newTestWakuTransfer*(
+    switch: Switch,
+    idsTx: AsyncQueue[ID],
+    wantsRx: AsyncQueue[(PeerId, Fingerprint)],
+    needsRx: AsyncQueue[(PeerId, Fingerprint)],
+): SyncTransfer =
+  let peerManager = PeerManager.new(switch)
+
+  let proto = SyncTransfer.new(
+    peerManager = peerManager,
+    wakuArchive = nil,
+    idsTx = idsTx,
+    wantsRx = wantsRx,
+    needsRx = needsRx,
+  )
+
+  proto.start()
+  switch.mount(proto)
+
+  return proto
diff --git a/tests/waku_store_sync/test_codec.nim b/tests/waku_store_sync/test_codec.nim
new file mode 100644
index 000000000..132c67c67
--- /dev/null
+++ b/tests/waku_store_sync/test_codec.nim
@@ -0,0 +1,197 @@
+{.used.}
+
+import std/[options, random], testutils/unittests, chronos
+
+import
+  ../../waku/waku_core,
+  ../../waku/waku_core/message/digest,
+  ../../waku/waku_core/time,
+  ../../waku/waku_store_sync,
+  ../../waku/waku_store_sync/common,
+  ../../waku/waku_store_sync/codec,
+  ./sync_utils
+
+proc randomItemSet(count: int, startTime: Timestamp, rng: var Rand): ItemSet =
+  var
+    elements = newSeqOfCap[ID](count)
+    lastTime = startTime
+
+  for i in 0 ..< count:
+    let diff = rng.rand(9.uint8) + 1
+
+    let timestamp = lastTime + diff * 1_000_000_000
+    lastTime = timestamp
+
+    let hash = randomHash(rng)
+
+    let id = ID(time: Timestamp(timestamp), fingerprint: hash)
+
+    elements.add(id)
+
+  return ItemSet(elements: elements, reconciled: true)
+
+proc randomSetRange(
+    count: int, startTime: Timestamp, rng: var Rand
+): (Slice[ID], ItemSet) =
+  let itemSet = randomItemSet(count, startTime, rng)
+
+  var
+    lb = itemSet.elements[0]
+    ub = itemSet.elements[^1]
+
+  #for test check equality
+  lb.fingerprint = EmptyFingerprint
+  ub.fingerprint = EmptyFingerprint
+
+  let bounds = lb .. ub
+
+  return (bounds, itemSet)
+
+suite "Waku Store Sync Codec":
+  test "empty item set encoding roundtrip":
+    var origItemSet = ItemSet()
+
+    origItemSet.reconciled = true
+
+    var encodedSet = origItemSet.deltaEncode()
+
+    var itemSet = ItemSet()
+    let _ = deltaDecode(itemSet, encodedSet, 0)
+
+    check:
+      origItemSet == itemSet
+
+  test "item set encoding roundtrip":
+    let
+      count = 10
+      time = getNowInNanosecondTime()
+
+    var rng = initRand()
+
+    let origItemSet = randomItemSet(count, time, rng)
+    var encodedSet = origItemSet.deltaEncode()
+
+    #faking a longer payload
+    let pad: seq[byte] =
+      @[0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0]
+    encodedSet &= pad
+
+    var itemSet = ItemSet()
+    let _ = deltaDecode(itemSet, encodedSet, count)
+
+    check:
+      origItemSet == itemSet
+
+  test "payload item set encoding roundtrip":
+    let count = 5
+
+    var
+      rng = initRand()
+      time = getNowInNanosecondTime()
+
+    let (bounds1, itemSet1) = randomSetRange(count, time, rng)
+    let (bounds2, itemSet2) = randomSetRange(count, time + 10_000_000_000, rng)
+    let (bounds3, itemSet3) = randomSetRange(count, time + 20_000_000_000, rng)
+    let (bounds4, itemSet4) = randomSetRange(count, time + 30_000_000_000, rng)
+
+    let range1 = (bounds1, RangeType.itemSetRange)
+    let range2 = (bounds2, RangeType.itemSetRange)
+    let range3 = (bounds3, RangeType.itemSetRange)
+    let range4 = (bounds4, RangeType.itemSetRange)
+
+    let payload = SyncPayload(
+      ranges: @[range1, range2, range3, range4],
+      fingerprints: @[],
+      itemSets: @[itemSet1, itemSet2, itemSet3, itemSet4],
+    )
+
+    let encodedPayload = payload.deltaEncode()
+
+    let decodedPayload = SyncPayload.deltaDecode(encodedPayload)
+
+    check:
+      payload.ranges[0][0].b == decodedPayload.ranges[0][0].b
+      payload.ranges[1][0].b == decodedPayload.ranges[1][0].b
+      payload.ranges[2][0].b == decodedPayload.ranges[2][0].b
+      payload.ranges[3][0].b == decodedPayload.ranges[3][0].b
+      payload.itemSets == decodedPayload.itemSets
+
+  test "payload fingerprint encoding roundtrip":
+    let count = 4
+
+    var
+      rng = initRand()
+      lastTime = getNowInNanosecondTime()
+      ranges = newSeqOfCap[(Slice[ID], RangeType)](4)
+
+    for i in 0 ..< count:
+      let lb = ID(time: Timestamp(lastTime), fingerprint: EmptyFingerprint)
+      #echo "lower bound: " & $lastTime
+      let nowTime = lastTime + 10_000_000_000 # 10s
+      #echo "upper bound: " & $nowTime
+      lastTime = nowTime
+      let ub = ID(time: Timestamp(nowTime), fingerprint: EmptyFingerprint)
+      let bounds = lb .. ub
+      let range = (bounds, RangeType.fingerprintRange)
+
+      ranges.add(range)
+
+    let payload = SyncPayload(
+      ranges: ranges,
+      fingerprints:
+        @[randomHash(rng), randomHash(rng), randomHash(rng), randomHash(rng)],
+      itemSets: @[],
+    )
+
+    let encodedPayload = payload.deltaEncode()
+    #echo "encoding done!"
+    let decodedPayload = SyncPayload.deltaDecode(encodedPayload)
+
+    check:
+      payload.ranges[0][0].b == decodedPayload.ranges[0][0].b
+      payload.ranges[1][0].b == decodedPayload.ranges[1][0].b
+      payload.ranges[2][0].b == decodedPayload.ranges[2][0].b
+      payload.ranges[3][0].b == decodedPayload.ranges[3][0].b
+      payload.fingerprints == decodedPayload.fingerprints
+
+  test "payload mixed encoding roundtrip":
+    let count = 2
+
+    var
+      rng = initRand()
+      lastTime = getNowInNanosecondTime()
+      ranges = newSeqOfCap[(Slice[ID], RangeType)](4)
+      itemSets = newSeqOfCap[ItemSet](4)
+      fingerprints = newSeqOfCap[Fingerprint](4)
+
+    for i in 1 .. count:
+      let lb = ID(time: Timestamp(lastTime), fingerprint: EmptyFingerprint)
+      let nowTime = lastTime + 10_000_000_000 # 10s
+      lastTime = nowTime
+      let ub = ID(time: Timestamp(nowTime), fingerprint: EmptyFingerprint)
+      let bounds = lb .. ub
+      let range = (bounds, RangeType.fingerprintRange)
+
+      ranges.add(range)
+      fingerprints.add(randomHash(rng))
+
+      let (bound, itemSet) = randomSetRange(5, lastTime, rng)
+      lastTime += 50_000_000_000 # 50s
+
+      ranges.add((bound, RangeType.itemSetRange))
+      itemSets.add(itemSet)
+
+    let payload =
+      SyncPayload(ranges: ranges, fingerprints: fingerprints, itemSets: itemSets)
+
+    let encodedPayload = payload.deltaEncode()
+    #echo "encoding done!"
+    let decodedPayload = SyncPayload.deltaDecode(encodedPayload)
+
+    check:
+      payload.ranges[0][0].b == decodedPayload.ranges[0][0].b
+      payload.ranges[1][0].b == decodedPayload.ranges[1][0].b
+      payload.ranges[2][0].b == decodedPayload.ranges[2][0].b
+      payload.ranges[3][0].b == decodedPayload.ranges[3][0].b
+      payload.fingerprints == decodedPayload.fingerprints
+      payload.itemSets == decodedPayload.itemSets
diff --git a/waku/waku_store_sync/codec.nim b/waku/waku_store_sync/codec.nim
new file mode 100644
index 000000000..d8594503c
--- /dev/null
+++ b/waku/waku_store_sync/codec.nim
@@ -0,0 +1,283 @@
+{.push raises: [].}
+
+import std/sequtils, stew/leb128
+
+import ../common/protobuf, ../waku_core/message, ../waku_core/time, ./common
+
+proc encode*(value: WakuMessagePayload): ProtoBuffer =
+  var pb = initProtoBuffer()
+
+  pb.write3(1, value.pubsub)
+  pb.write3(2, value.message.encode())
+
+  return pb
+
+proc deltaEncode*(itemSet: ItemSet): seq[byte] =
+  let capacity = 1 + (itemSet.elements.len * 41)
+
+  var
+    output = newSeqOfCap[byte](capacity)
+    lastTime = Timestamp(0)
+    buf = Leb128Buf[uint64]()
+
+  for id in itemSet.elements:
+    let timeDiff = uint64(id.time) - uint64(lastTime)
+    lastTime = id.time
+
+    # encode timestamp
+    buf = timediff.toBytes(Leb128)
+    output &= @buf
+
+    output &= id.fingerprint
+
+  output &= byte(itemSet.reconciled)
+
+  return output
+
+proc deltaEncode*(value: SyncPayload): seq[byte] =
+  if value.ranges.len == 0:
+    return @[0]
+
+  var
+    output = newSeqOfCap[byte](1000)
+    buf = Leb128Buf[uint64]()
+    lastTimestamp: Timestamp
+    lastHash: Fingerprint
+    i = 0
+    j = 0
+
+  # the first range is implicit but must be explicit when encoded
+  let (bound, _) = value.ranges[0]
+
+  lastTimestamp = bound.a.time
+  lastHash = bound.a.fingerprint
+
+  # encode first timestamp
+  buf = uint64(lastTimestamp).toBytes(Leb128)
+  output &= @buf
+
+  #echo "First Timestamp: " & $lastTimestamp
+
+  # implicit first fingerprint is always 0 and range type is always skip
+
+  for (bound, rangeType) in value.ranges:
+    let timeDiff = uint64(bound.b.time) - uint64(lastTimestamp)
+    lastTimestamp = bound.b.time
+
+    # encode timestamp
+    buf = timeDiff.toBytes(Leb128)
+    output &= @buf
+
+    #echo "Timestamp: " & $timeDiff
+
+    if timeDiff == 0:
+      var sameBytes = 0
+      for (byte1, byte2) in zip(lastHash, bound.b.fingerprint):
+        sameBytes.inc()
+
+        if byte1 != byte2:
+          break
+
+      # encode number of same bytes
+      output &= byte(sameBytes)
+
+      #echo "Same Bytes: " & $sameBytes
+
+      # encode fingerprint bytes
+      output &= bound.b.fingerprint[0 ..< sameBytes]
+
+    # encode rangeType
+    output &= byte(rangeType)
+
+    case rangeType
+    of skipRange:
+      #echo "Skip Range"
+      continue
+    of fingerprintRange:
+      let fingerprint = value.fingerprints[i]
+      i.inc()
+
+      #echo "Encode Fingerprint"
+
+      output &= fingerprint
+    of itemSetRange:
+      let itemSet = value.itemSets[j]
+      j.inc()
+
+      # encode how many elements are in the set
+      buf = uint64(itemSet.elements.len).toBytes(Leb128)
+      output &= @buf
+
+      #echo "Set elements: " & $itemSet.elements.len
+
+      let encodedSet = itemSet.deltaEncode()
+
+      #echo "Encoded Set"
+
+      output &= encodedSet
+
+    continue
+
+  return output
+
+proc deltaDecode*(itemSet: var ItemSet, buffer: seq[byte], setLength: int): int =
+  var
+    lastTime = Timestamp(0)
+    val = 0.uint64
+    len = 0.int8
+    idx = 0
+
+  while itemSet.elements.len < setLength:
+    var slice = buffer[idx ..< idx + 9]
+    (val, len) = uint64.fromBytes(slice, Leb128)
+    idx += len
+
+    let time = lastTime + Timestamp(val)
+    lastTime = time
+
+    #echo "Timestamp: " & $time
+    #echo "IDX: " & $idx
+
+    slice = buffer[idx ..< idx + 32]
+    idx += 32
+    var fingerprint = EmptyFingerprint
+    for i, bytes in slice:
+      fingerprint[i] = bytes
+
+    #echo "Hash: " & $fingerprint
+    #echo "IDX: " & $idx
+
+    let id = ID(time: time, fingerprint: fingerprint)
+
+    itemSet.elements.add(id)
+
+  itemSet.reconciled = bool(buffer[idx])
+  idx += 1
+
+  #echo "Reconciled: " & $itemSet.reconciled
+  #echo "IDX: " & $idx
+
+  return idx
+
+proc deltaDecode*(T: type SyncPayload, buffer: seq[byte]): T =
+  #echo "buffer length: " & $buffer.len
+
+  if buffer.len == 1:
+    return SyncPayload()
+
+  var
+    payload = SyncPayload()
+    lastTime = Timestamp(0)
+    val = 0.uint64
+    len = 0.int8
+    idx = 0
+    slice = buffer[idx ..< idx + 9]
+
+  # first timestamp
+  (val, len) = uint64.fromBytes(slice, Leb128)
+  idx += len
+  lastTime = Timestamp(val)
+
+  #echo "First Range Timestamp: " & $lastTime
+  #echo "IDX: " & $idx
+
+  # implicit first fingerprint is always 0 
+  # implicit first range mode is alway skip
+
+  while idx < buffer.len - 1:
+    let lowerRangeBound = ID(time: lastTime, fingerprint: EmptyFingerprint)
+
+    # decode timestamp diff
+    let min = min(idx + 9, buffer.len)
+    slice = buffer[idx ..< min]
+    (val, len) = uint64.fromBytes(slice, Leb128)
+    idx += len
+    let timeDiff = Timestamp(val)
+
+    #echo "Range Timestamp diff: " & $timeDiff
+    #echo "IDX: " & $idx
+
+    var fingerprint = EmptyFingerprint
+    if timeDiff == 0:
+      # decode number of same bytes
+      let sameBytes = int(buffer[idx])
+      idx += 1
+
+      #echo "Same Bytes Count: " & $sameBytes
+      #echo "IDX: " & $idx
+
+      # decode same bytes
+      slice = buffer[idx ..< idx + sameBytes]
+      idx += sameBytes
+      for i, bytes in slice:
+        fingerprint[i] = bytes
+
+      #echo "Same Bytes: " & $fingerprint
+      #echo "IDX: " & $idx
+
+    let thisTime = lastTime + timeDiff
+    lastTime = thisTime
+
+    #echo "Range Timestamp: " & $thisTime
+
+    let upperRangeBound = ID(time: thisTime, fingerprint: fingerprint)
+
+    let bounds = lowerRangeBound .. upperRangeBound
+
+    # decode range type
+    let rangeType = RangeType(buffer[idx])
+    idx += 1
+
+    #echo "Range Type: " & $rangeType
+    #echo "IDX: " & $idx
+
+    payload.ranges.add((bounds, rangeType))
+
+    if rangeType == fingerprintRange:
+      # decode fingerprint
+      slice = buffer[idx ..< idx + 32]
+      idx += 32
+      var fingerprint = EmptyFingerprint
+      for i, bytes in slice:
+        fingerprint[i] = bytes
+
+      #echo "Fingerprint: " & $fingerprint
+      #echo "IDX: " & $idx
+
+      payload.fingerprints.add(fingerprint)
+    elif rangeType == itemSetRange:
+      # decode item set length
+      let min = min(idx + 9, buffer.len)
+      slice = buffer[idx ..< min]
+      (val, len) = uint64.fromBytes(slice, Leb128)
+      idx += len
+      let itemSetLength = int(val)
+
+      #echo "Set length: " & $itemSetLength
+      #echo "IDX: " & $idx
+
+      # decode item set
+      var itemSet = ItemSet()
+      slice = buffer[idx ..< buffer.len]
+      let count = deltaDecode(itemSet, slice, itemSetLength)
+      idx += count
+
+      #echo "Set Decoded"
+      #echo "IDX: " & $idx
+
+      payload.itemSets.add(itemSet)
+
+  return payload
+
+proc decode*(T: type WakuMessagePayload, buffer: seq[byte]): ProtobufResult[T] =
+  let pb = initProtoBuffer(buffer)
+
+  var pubsub: string
+  discard ?pb.getField(1, pubsub)
+
+  var proto: ProtoBuffer
+  discard ?pb.getField(2, proto)
+
+  let message = ?WakuMessage.decode(proto.buffer)
+
+  return ok(WakuMessagePayload(pubsub: pubsub, message: message))
diff --git a/waku/waku_store_sync/common.nim b/waku/waku_store_sync/common.nim
new file mode 100644
index 000000000..fd0bc8faa
--- /dev/null
+++ b/waku/waku_store_sync/common.nim
@@ -0,0 +1,80 @@
+{.push raises: [].}
+
+import std/[options], chronos, stew/[byteutils]
+
+import ../waku_core
+
+const
+  DefaultSyncInterval*: Duration = 5.minutes
+  DefaultSyncRange*: Duration = 1.hours
+  RetryDelay*: Duration = 30.seconds
+  SyncReconciliationCodec* = "/vac/waku/reconciliation/1.0"
+  SyncTransferCodec* = "/vac/waku/transfer/1.0"
+  DefaultGossipSubJitter*: Duration = 20.seconds
+
+type
+  Fingerprint* = array[32, byte]
+
+  ID* = object
+    time*: Timestamp
+    fingerprint*: Fingerprint
+
+  ItemSet* = object
+    elements*: seq[ID]
+    reconciled*: bool
+
+  RangeType* = enum
+    skipRange = 0
+    fingerprintRange = 1
+    itemSetRange = 2
+
+  SyncPayload* = object
+    ranges*: seq[(Slice[ID], RangeType)]
+    fingerprints*: seq[Fingerprint]
+    itemSets*: seq[ItemSet]
+
+  WakuMessagePayload* = object
+    pubsub*: string
+    message*: WakuMessage
+
+const EmptyFingerprint*: Fingerprint = [
+  0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+  0, 0, 0,
+]
+
+const FullFingerprint*: Fingerprint = [
+  255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
+  255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
+]
+
+proc high*(T: type ID): T =
+  return ID(time: Timestamp(high(int64)), fingerprint: FullFingerprint)
+
+proc low*(T: type ID): T =
+  return ID(time: Timestamp(low(int64)), fingerprint: EmptyFingerprint)
+
+proc `$`*(value: ID): string =
+  return '(' & $value.time & ", " & $value.fingerprint & ')'
+
+proc cmp(x, y: Fingerprint): int =
+  if x < y:
+    return -1
+  elif x == y:
+    return 0
+
+  return 1
+
+proc cmp*(x, y: ID): int =
+  if x.time == y.time:
+    return cmp(x.fingerprint, y.fingerprint)
+
+  if x.time < y.time:
+    return -1
+
+  return 1
+
+proc `<`*(x, y: ID): bool =
+  cmp(x, y) == -1
+
+proc `>`*(x, y: ID): bool =
+  cmp(x, y) == 1