diff --git a/benchmarks/repostore_rw_bench.nim b/benchmarks/repostore_rw_bench.nim
new file mode 100644
index 00000000..d3f3ee87
--- /dev/null
+++ b/benchmarks/repostore_rw_bench.nim
@@ -0,0 +1,110 @@
+import std/tempfiles
+import std/times
+import std/random
+import std/os
+
+import pkg/chronos
+import pkg/datastore
+
+import pkg/codex/blocktype
+import pkg/codex/merkletree/codex
+import pkg/codex/manifest
+import pkg/codex/stores/[filestore, repostore]
+
+const
+  NBlocks = 81_920
+  BlockSize = 65_536
+  DataDir = ""
+
+type Dataset* = tuple[blocks: seq[Block], tree: CodexTree, manifest: Manifest]
+
+template benchmark*(name: string, blk: untyped) =
+  let t0 = epochTime()
+  blk
+  let elapsed = epochTime() - t0
+  echo name, " ", elapsed.formatFloat(format = ffDecimal, precision = 3), " s"
+
+proc makeRandomBlock*(size: NBytes): Block =
+  let bytes = newSeqWith(size.int, rand(uint8))
+  Block.new(bytes).tryGet()
+
+proc makeDataset*(nblocks: int, blockSize: int): ?!Dataset =
+  echo "Generate dataset with ", nblocks, " blocks of ", blockSize, " bytes each."
+
+  let
+    blocks = newSeqWith(nblocks, makeRandomBlock(NBytes(blockSize)))
+    tree = ?CodexTree.init(blocks.mapIt(it.cid))
+    treeCid = ?tree.rootCid
+    manifest = Manifest.new(
+      treeCid = treeCid,
+      blockSize = NBytes(blockSize),
+      datasetSize = NBytes(nblocks * blockSize),
+    )
+
+  return success((blocks, tree, manifest))
+
+proc newRepostore(dataDir: string): RepoStore =
+  let blockStore =
+    FSDatastore.new(dataDir, depth = 5).expect("Should create repo file data store!")
+  let repoStore = RepoStore.new(
+    blockStore,
+    LevelDbDatastore.new(dataDir / "meta").expect("Should create metadata store!"),
+    quotaMaxBytes = 10_000_000_000'nb,
+  )
+  repoStore
+
+proc asBlock(m: Manifest): Block =
+  let mdata = m.encode().tryGet()
+  Block.new(data = mdata, codec = ManifestCodec).tryGet()
+
+proc writeData(
+    dataset: Dataset, store: RepoStore
+): Future[void] {.async: (raises: [CatchableError]).} =
+  let (blocks, tree, manifest) = dataset
+
+  for i in 0 ..< NBlocks:
+    (await store.putBlock(blocks[i])).tryGet()
+
+  (await store.putBlock(manifest.asBlock())).tryGet()
+
+proc writeData(
+    dataset: Dataset, store: FileStore
+): Future[void] {.async: (raises: [CatchableError]).} =
+  let (blocks, tree, manifest) = dataset
+
+  let file = store.create(manifest).tryGet()
+
+  for i in 0 ..< NBlocks:
+    (await file.putBlock(i, blocks[i])).tryGet()
+
+proc runRepostoreBench(
+    dataset: Dataset
+): Future[void] {.async: (raises: [CatchableError]).} =
+  let
+    dir = createTempDir("repostore-bench", "")
+    store = newRepostore(dir)
+
+  echo "Store dir is ", dir
+  defer:
+    removeDir(dir)
+
+  benchmark "filestore write data":
+    await writeData(dataset, store)
+
+proc runFilestoreBench(
+    dataset: Dataset
+): Future[void] {.async: (raises: [CatchableError]).} =
+  let
+    dir = createTempDir("filestore-bench", "")
+    store = FileStore(root: dir)
+
+  echo "Store dir is ", dir
+  defer:
+    removeDir(dir)
+
+  benchmark "repostore write data":
+    await writeData(dataset, store)
+
+let dataset = makeDataset(NBlocks, BlockSize).tryGet()
+waitFor runRepostoreBench(dataset)
+waitFor runFilestoreBench(dataset)
diff --git a/codex/stores/filestore.nim b/codex/stores/filestore.nim
new file mode 100644
index 00000000..d4f41ab7
--- /dev/null
+++ b/codex/stores/filestore.nim
@@ -0,0 +1,95 @@
+import std/posix
+import std/strformat
+
+import ../manifest/manifest
+import ../blocktype
+import ../utils
+import ../utils/json
+
+import pkg/libp2p/protobuf/minprotobuf
+import pkg/libp2p/[cid, multihash, multicodec]
+import pkg/questionable/results
+
+import ../errors
+import ../units
+import ../blocktype
+import ../indexingstrategy
+import ../logutils
+
+const DefaultBlockSize*: uint = 65536
+
+type FileStore* = object
+  root*: string
+
+type File* = object
+  manifest: Manifest
+  filepath: string
+  fd*: cint
+
+proc allocStorage*(filepath: string, size: int): ?!cint =
+  let fd = open(filepath, O_CREAT or O_RDWR or O_TRUNC, 0o644)
+  if fd < 0:
+    return failure(&"open failed with error {fd}")
+
+  let rc = posix_fallocate(fd, 0, size)
+  if rc != 0:
+    return failure(&"posix_fallocate failed with error {rc}")
+
+  success(fd)
+
+proc open*(self: var File): ?!void =
+  self.fd = open(self.filepath, O_RDWR)
+  if self.fd < 0:
+    return failure(&"open failed with error {self.fd}")
+
+  success()
+
+proc initDataset*(filepath: string, manifest: Manifest): ?!File =
+  let fd = ?allocStorage(filepath, manifest.datasetSize.int)
+  success(File(manifest: manifest, filepath: filepath, fd: fd))
+
+proc ensureOpen*(self: File): ?!void =
+  if self.fd < 0:
+    return failure("dataset is not open")
+  success()
+
+proc getBlock*(
+    self: File, index: int
+): Future[?!Block] {.async: (raises: [CatchableError]).} =
+  ?self.ensureOpen()
+
+  if index > self.manifest.blocksCount:
+    return failure(&"index out of bounds")
+
+  let
+    blockSize = self.manifest.blockSize.int
+    offset = index * blockSize
+    buf = newSeqWith(blockSize, 0.byte)
+    rc = pread(self.fd, addr(buf[0]), blockSize, offset)
+
+  if rc != blockSize:
+    return failure(&"pread failed with error {rc}")
+
+  Block.new(data = buf)
+
+proc putBlock*(
+    self: File, index: int, blk: Block
+): Future[?!void] {.async: (raises: [CatchableError]).} =
+  ?self.ensureOpen()
+
+  if index > self.manifest.blocksCount:
+    return failure(&"index out of bounds")
+
+  let
+    blockSize = self.manifest.blockSize.int
+    offset = index * blockSize
+    rc = pwrite(self.fd, addr(blk.data[0]), blockSize, offset)
+
+  if rc != blockSize:
+    return failure(&"pwrite failed with error {rc}")
+
+  success()
+
+proc create*(self: FileStore, manifest: Manifest): ?!File =
+  let path = self.root & "/" & $manifest.treeCid
+  initDataset(path, manifest)