diff --git a/datastore/memoryds.nim b/datastore/memoryds.nim
new file mode 100644
index 0000000..c4d735e
--- /dev/null
+++ b/datastore/memoryds.nim
@@ -0,0 +1,96 @@
+import std/tables
+
+import pkg/chronos
+import pkg/questionable
+import pkg/questionable/results
+import pkg/upraises
+
+import ./key
+import ./query
+import ./datastore
+
+export key, query
+
+push: {.upraises: [].}
+
+type
+  MemoryStore* = object
+    store*: Datastore
+    key*: Key
+
+  MemoryDatastore* = ref object of Datastore
+    stores*: Table[Key, MemoryStore]
+
+method has*(
+  self: MemoryDatastore,
+  key: Key): Future[?!bool] {.async.} =
+
+  without mounted =? self.dispatch(key):
+    return failure "No mounted datastore found"
+
+  return (await mounted.store.store.has(mounted.relative))
+
+method delete*(
+  self: MemoryDatastore,
+  key: Key): Future[?!void] {.async.} =
+
+  without mounted =? self.dispatch(key), error:
+    return failure(error)
+
+  return (await mounted.store.store.delete(mounted.relative))
+
+method delete*(
+  self: MemoryDatastore,
+  keys: seq[Key]): Future[?!void] {.async.} =
+
+  for key in keys:
+    if err =? (await self.delete(key)).errorOption:
+      return failure err
+
+  return success()
+
+method get*(
+  self: MemoryDatastore,
+  key: Key): Future[?!seq[byte]] {.async.} =
+
+  without mounted =? self.dispatch(key), error:
+    return failure(error)
+
+  return await mounted.store.store.get(mounted.relative)
+
+method put*(
+  self: MemoryDatastore,
+  key: Key,
+  data: seq[byte]): Future[?!void] {.async.} =
+
+  without mounted =? self.dispatch(key), error:
+    return failure(error)
+
+  return (await mounted.store.store.put(mounted.relative, data))
+
+method put*(
+  self: MemoryDatastore,
+  batch: seq[BatchEntry]): Future[?!void] {.async.} =
+
+  for entry in batch:
+    if err =? (await self.put(entry.key, entry.data)).errorOption:
+      return failure err
+
+  return success()
+
+method close*(self: MemoryDatastore): Future[?!void] {.async.} =
+  for s in self.stores.values:
+    discard await s.store.close()
+
+  # TODO: how to handle failed close?
+  return success()
+
+func new*(
+  T: type MemoryDatastore,
+  stores: Table[Key, Datastore] = initTable[Key, Datastore]()): ?!T =
+
+  var self = T()
+  for (k, v) in stores.pairs:
+    self.stores[?k.path] = MemoryStore(store: v, key: k)
+
+  success self
diff --git a/tests/datastore/testmemoryds.nim b/tests/datastore/testmemoryds.nim
new file mode 100644
index 0000000..626d98d
--- /dev/null
+++ b/tests/datastore/testmemoryds.nim
@@ -0,0 +1,138 @@
+import std/options
+import std/sequtils
+import std/os
+from std/algorithm import sort, reversed
+
+import pkg/asynctest/unittest2
+import pkg/chronos
+import pkg/stew/results
+import pkg/stew/byteutils
+
+import pkg/datastore/fsds
+
+import ./dscommontests
+import ./querycommontests
+
+suite "Test Basic MemoryDatastore":
+  let
+    path = currentSourcePath() # get this file's name
+    basePath = "tests_data"
+    basePathAbs = path.parentDir / basePath
+    key = Key.init("/a/b").tryGet()
+    bytes = "some bytes".toBytes
+    otherBytes = "some other bytes".toBytes
+
+  var
+    fsStore: MemoryDatastore
+
+  setupAll:
+    removeDir(basePathAbs)
+    require(not dirExists(basePathAbs))
+    createDir(basePathAbs)
+
+    fsStore = MemoryDatastore.new(root = basePathAbs, depth = 3).tryGet()
+
+  teardownAll:
+    removeDir(basePathAbs)
+    require(not dirExists(basePathAbs))
+
+  basicStoreTests(fsStore, key, bytes, otherBytes)
+
+suite "Test Misc MemoryDatastore":
+  let
+    path = currentSourcePath() # get this file's name
+    basePath = "tests_data"
+    basePathAbs = path.parentDir / basePath
+    bytes = "some bytes".toBytes
+
+  setup:
+    removeDir(basePathAbs)
+    require(not dirExists(basePathAbs))
+    createDir(basePathAbs)
+
+  teardown:
+    removeDir(basePathAbs)
+    require(not dirExists(basePathAbs))
+
+  test "Test validDepth()":
+    let
+      fs = MemoryDatastore.new(root = "/", depth = 3).tryGet()
+      invalid = Key.init("/a/b/c/d").tryGet()
+      valid = Key.init("/a/b/c").tryGet()
+
+    check:
+      not fs.validDepth(invalid)
+      fs.validDepth(valid)
+
+  test "Test invalid key (path) depth":
+    let
+      fs = MemoryDatastore.new(root = basePathAbs, depth = 3).tryGet()
+      key = Key.init("/a/b/c/d").tryGet()
+
+    check:
+      (await fs.put(key, bytes)).isErr
+      (await fs.get(key)).isErr
+      (await fs.delete(key)).isErr
+      (await fs.has(key)).isErr
+
+  test "Test valid key (path) depth":
+    let
+      fs = MemoryDatastore.new(root = basePathAbs, depth = 3).tryGet()
+      key = Key.init("/a/b/c").tryGet()
+
+    check:
+      (await fs.put(key, bytes)).isOk
+      (await fs.get(key)).isOk
+      (await fs.delete(key)).isOk
+      (await fs.has(key)).isOk
+
+  test "Test key cannot write outside of root":
+    let
+      fs = MemoryDatastore.new(root = basePathAbs, depth = 3).tryGet()
+      key = Key.init("/a/../../c").tryGet()
+
+    check:
+      (await fs.put(key, bytes)).isErr
+      (await fs.get(key)).isErr
+      (await fs.delete(key)).isErr
+      (await fs.has(key)).isErr
+
+  test "Test key cannot convert to invalid path":
+    let
+      fs = MemoryDatastore.new(root = basePathAbs).tryGet()
+
+    for c in invalidFilenameChars:
+      if c == ':': continue
+      if c == '/': continue
+
+      let
+        key = Key.init("/" & c).tryGet()
+
+      check:
+        (await fs.put(key, bytes)).isErr
+        (await fs.get(key)).isErr
+        (await fs.delete(key)).isErr
+        (await fs.has(key)).isErr
+
+suite "Test Query":
+  let
+    path = currentSourcePath() # get this file's name
+    basePath = "tests_data"
+    basePathAbs = path.parentDir / basePath
+
+  var
+    ds: MemoryDatastore
+
+  setup:
+    removeDir(basePathAbs)
+    require(not dirExists(basePathAbs))
+    createDir(basePathAbs)
+
+    ds = MemoryDatastore.new(root = basePathAbs, depth = 5).tryGet()
+
+  teardown:
+
+    removeDir(basePathAbs)
+    require(not dirExists(basePathAbs))
+
+  queryTests(ds, false)