diff --git a/package.json b/package.json
index 93ee999..d568469 100644
--- a/package.json
+++ b/package.json
@@ -15,8 +15,8 @@
     "filesystem"
   ],
   "dependencies": {
-    "level-filesystem": "^1.0.1",
-    "levelup": "^0.18.2"
+    "level-filesystem": "1.2.0",
+    "levelup": "4.1.0"
   },
   "peerDependencies": {
     "asyncstorage-down": ">=3.0.0 <5.0.0"
diff --git a/yarn.lock b/yarn.lock
new file mode 100644
index 0000000..1271c58
--- /dev/null
+++ b/yarn.lock
@@ -0,0 +1,319 @@
+# THIS IS AN AUTOGENERATED FILE. DO NOT EDIT THIS FILE DIRECTLY.
+# yarn lockfile v1
+
+
+abstract-leveldown@~6.0.0:
+  version "6.0.3"
+  resolved "https://registry.yarnpkg.com/abstract-leveldown/-/abstract-leveldown-6.0.3.tgz#b4b6159343c74b0c5197b2817854782d8f748c4a"
+  integrity sha512-jzewKKpZbaYUa6HTThnrl+GrJhzjEAeuc7hTVpZdzg7kupXZFoqQDFwyOwLNbmJKJlmzw8yiipMPkDiuKkT06Q==
+  dependencies:
+    level-concat-iterator "~2.0.0"
+    xtend "~4.0.0"
+
+buffer-from@^1.0.0:
+  version "1.1.1"
+  resolved "https://registry.yarnpkg.com/buffer-from/-/buffer-from-1.1.1.tgz#32713bc028f75c02fdb710d7c7bcec1f2c6070ef"
+  integrity sha512-MQcXEUbCKtEo7bhqEs6560Hyd4XaovZlO/k9V3hjVUF/zwW7KBVdSK4gIt/bzwS9MbR5qob+F5jusZsb0YQK2A==
+
+clone@~0.1.9:
+  version "0.1.19"
+  resolved "https://registry.yarnpkg.com/clone/-/clone-0.1.19.tgz#613fb68639b26a494ac53253e15b1a6bd88ada85"
+  integrity sha1-YT+2hjmyaklKxTJT4Vsaa9iK2oU=
+
+concat-stream@^1.4.4:
+  version "1.6.2"
+  resolved "https://registry.yarnpkg.com/concat-stream/-/concat-stream-1.6.2.tgz#904bdf194cd3122fc675c77fc4ac3d4ff0fd1a34"
+  integrity sha512-27HBghJxjiZtIk3Ycvn/4kbJk/1uZuJFfuPEns6LaEvpvG1f0hTea8lilrouyo9mVc2GWdcEZ8OLoGmSADlrCw==
+  dependencies:
+    buffer-from "^1.0.0"
+    inherits "^2.0.3"
+    readable-stream "^2.2.2"
+    typedarray "^0.0.6"
+
+core-util-is@~1.0.0:
+  version "1.0.2"
+  resolved "https://registry.yarnpkg.com/core-util-is/-/core-util-is-1.0.2.tgz#b5fd54220aa2bc5ab57aab7140c940754503c1a7"
+  integrity sha1-tf1UIgqivFq1eqtxQMlAdUUDwac=
+
+deferred-leveldown@~5.1.0:
+  version "5.1.0"
+  resolved "https://registry.yarnpkg.com/deferred-leveldown/-/deferred-leveldown-5.1.0.tgz#c21e40641a8e48530255a4ad31371cc7fe76b332"
+  integrity sha512-PvDY+BT2ONu2XVRgxHb77hYelLtMYxKSGuWuJJdVRXh9ntqx9GYTFJno/SKAz5xcd+yjQwyQeIZrUPjPvA52mg==
+  dependencies:
+    abstract-leveldown "~6.0.0"
+    inherits "^2.0.3"
+
+errno@^0.1.1, errno@~0.1.1:
+  version "0.1.7"
+  resolved "https://registry.yarnpkg.com/errno/-/errno-0.1.7.tgz#4684d71779ad39af177e3f007996f7c67c852618"
+  integrity sha512-MfrRBDWzIWifgq6tJj60gkAwtLNb6sQPlcFrSOflcP1aFmmruKQ2wRnze/8V6kgyz7H3FF8Npzv78mZ7XLLflg==
+  dependencies:
+    prr "~1.0.1"
+
+foreach@~2.0.1:
+  version "2.0.5"
+  resolved "https://registry.yarnpkg.com/foreach/-/foreach-2.0.5.tgz#0bee005018aeb260d0a3af3ae658dd0136ec1b99"
+  integrity sha1-C+4AUBiusmDQo6865ljdATbsG5k=
+
+fwd-stream@^1.0.4:
+  version "1.0.4"
+  resolved "https://registry.yarnpkg.com/fwd-stream/-/fwd-stream-1.0.4.tgz#ed281cabed46feecf921ee32dc4c50b372ac7cfa"
+  integrity sha1-7Sgcq+1G/uz5Ie4y3ExQs3KsfPo=
+  dependencies:
+    readable-stream "~1.0.26-4"
+
+indexof@~0.0.1:
+  version "0.0.1"
+  resolved "https://registry.yarnpkg.com/indexof/-/indexof-0.0.1.tgz#82dc336d232b9062179d05ab3293a66059fd435d"
+  integrity sha1-gtwzbSMrkGIXnQWrMpOmYFn9Q10=
+
+inherits@^2.0.1, inherits@^2.0.3, inherits@~2.0.1, inherits@~2.0.3:
+  version "2.0.4"
+  resolved "https://registry.yarnpkg.com/inherits/-/inherits-2.0.4.tgz#0fa2c64f932917c3433a0ded55363aae37416b7c"
+  integrity sha512-k/vGaX4/Yla3WzyMCvTQOXYeIHvqOKtnqBduzTHpzpQZzAskKMhZ2K+EnBiSM9zGSoIFeMpXKxa4dYeZIQqewQ==
+
+is-object@~0.1.2:
+  version "0.1.2"
+  resolved "https://registry.yarnpkg.com/is-object/-/is-object-0.1.2.tgz#00efbc08816c33cfc4ac8251d132e10dc65098d7"
+  integrity sha1-AO+8CIFsM8/ErIJR0TLhDcZQmNc=
+
+is@~0.2.6:
+  version "0.2.7"
+  resolved "https://registry.yarnpkg.com/is/-/is-0.2.7.tgz#3b34a2c48f359972f35042849193ae7264b63562"
+  integrity sha1-OzSixI81mXLzUEKEkZOucmS2NWI=
+
+isarray@0.0.1:
+  version "0.0.1"
+  resolved "https://registry.yarnpkg.com/isarray/-/isarray-0.0.1.tgz#8a18acfca9a8f4177e09abfc6038939b05d1eedf"
+  integrity sha1-ihis/Kmo9Bd+Cav8YDiTmwXR7t8=
+
+isarray@~1.0.0:
+  version "1.0.0"
+  resolved "https://registry.yarnpkg.com/isarray/-/isarray-1.0.0.tgz#bb935d48582cba168c06834957a54a3e07124f11"
+  integrity sha1-u5NdSFgsuhaMBoNJV6VKPgcSTxE=
+
+level-blobs@^0.1.7:
+  version "0.1.7"
+  resolved "https://registry.yarnpkg.com/level-blobs/-/level-blobs-0.1.7.tgz#9ab9b97bb99f1edbf9f78a3433e21ed56386bdaf"
+  integrity sha1-mrm5e7mfHtv594o0M+Ie1WOGva8=
+  dependencies:
+    level-peek "1.0.6"
+    once "^1.3.0"
+    readable-stream "^1.0.26-4"
+
+level-concat-iterator@~2.0.0:
+  version "2.0.1"
+  resolved "https://registry.yarnpkg.com/level-concat-iterator/-/level-concat-iterator-2.0.1.tgz#1d1009cf108340252cb38c51f9727311193e6263"
+  integrity sha512-OTKKOqeav2QWcERMJR7IS9CUo1sHnke2C0gkSmcR7QuEtFNLLzHQAvnMw8ykvEcv0Qtkg0p7FOwP1v9e5Smdcw==
+
+level-errors@~2.0.0:
+  version "2.0.1"
+  resolved "https://registry.yarnpkg.com/level-errors/-/level-errors-2.0.1.tgz#2132a677bf4e679ce029f517c2f17432800c05c8"
+  integrity sha512-UVprBJXite4gPS+3VznfgDSU8PTRuVX0NXwoWW50KLxd2yw4Y1t2JUR5In1itQnudZqRMT9DlAM3Q//9NCjCFw==
+  dependencies:
+    errno "~0.1.1"
+
+level-filesystem@1.2.0:
+  version "1.2.0"
+  resolved "https://registry.yarnpkg.com/level-filesystem/-/level-filesystem-1.2.0.tgz#a00aca9919c4a4dfafdca6a8108d225aadff63b3"
+  integrity sha1-oArKmRnEpN+v3KaoEI0iWq3/Y7M=
+  dependencies:
+    concat-stream "^1.4.4"
+    errno "^0.1.1"
+    fwd-stream "^1.0.4"
+    level-blobs "^0.1.7"
+    level-peek "^1.0.6"
+    level-sublevel "^5.2.0"
+    octal "^1.0.0"
+    once "^1.3.0"
+    xtend "^2.2.0"
+
+level-fix-range@2.0:
+  version "2.0.0"
+  resolved "https://registry.yarnpkg.com/level-fix-range/-/level-fix-range-2.0.0.tgz#c417d62159442151a19d9a2367868f1724c2d548"
+  integrity sha1-xBfWIVlEIVGhnZojZ4aPFyTC1Ug=
+  dependencies:
+    clone "~0.1.9"
+
+level-fix-range@~1.0.2:
+  version "1.0.2"
+  resolved "https://registry.yarnpkg.com/level-fix-range/-/level-fix-range-1.0.2.tgz#bf15b915ae36d8470c821e883ddf79cd16420828"
+  integrity sha1-vxW5Fa422EcMgh6IPd95zRZCCCg=
+
+"level-hooks@>=4.4.0 <5":
+  version "4.5.0"
+  resolved "https://registry.yarnpkg.com/level-hooks/-/level-hooks-4.5.0.tgz#1b9ae61922930f3305d1a61fc4d83c8102c0dd93"
+  integrity sha1-G5rmGSKTDzMF0aYfxNg8gQLA3ZM=
+  dependencies:
+    string-range "~1.2"
+
+level-iterator-stream@~4.0.0:
+  version "4.0.1"
+  resolved "https://registry.yarnpkg.com/level-iterator-stream/-/level-iterator-stream-4.0.1.tgz#65c467070c0788fe0d08a0c1ed600c3b9e82bc8d"
+  integrity sha512-pSZWqXK6/yHQkZKCHrR59nKpU5iqorKM22C/BOHTb/cwNQ2EOZG+bovmFFGcOgaBoF3KxqJEI27YwewhJQTzsw==
+  dependencies:
+    inherits "^2.0.1"
+    readable-stream "^3.0.2"
+    xtend "^4.0.0"
+
+level-peek@1.0.6, level-peek@^1.0.6:
+  version "1.0.6"
+  resolved "https://registry.yarnpkg.com/level-peek/-/level-peek-1.0.6.tgz#bec51c72a82ee464d336434c7c876c3fcbcce77f"
+  integrity sha1-vsUccqgu5GTTNkNMfIdsP8vM538=
+  dependencies:
+    level-fix-range "~1.0.2"
+
+level-sublevel@^5.2.0:
+  version "5.2.3"
+  resolved "https://registry.yarnpkg.com/level-sublevel/-/level-sublevel-5.2.3.tgz#744c12c72d2e72be78dde3b9b5cd84d62191413a"
+  integrity sha1-dEwSxy0ucr543eO5tc2E1iGRQTo=
+  dependencies:
+    level-fix-range "2.0"
+    level-hooks ">=4.4.0 <5"
+    string-range "~1.2.1"
+    xtend "~2.0.4"
+
+levelup@4.1.0:
+  version "4.1.0"
+  resolved "https://registry.yarnpkg.com/levelup/-/levelup-4.1.0.tgz#49ab5d3a341731cd102f91c6bc17a1acb1969a17"
+  integrity sha512-+Qhe2/jb5affN7BeFgWUUWVdYoGXO2nFS3QLEZKZynnQyP9xqA+7wgOz3fD8SST2UKpHQuZgjyJjTcB2nMl2dQ==
+  dependencies:
+    deferred-leveldown "~5.1.0"
+    level-errors "~2.0.0"
+    level-iterator-stream "~4.0.0"
+    xtend "~4.0.0"
+
+object-keys@~0.2.0:
+  version "0.2.0"
+  resolved "https://registry.yarnpkg.com/object-keys/-/object-keys-0.2.0.tgz#cddec02998b091be42bf1035ae32e49f1cb6ea67"
+  integrity sha1-zd7AKZiwkb5CvxA1rjLknxy26mc=
+  dependencies:
+    foreach "~2.0.1"
+    indexof "~0.0.1"
+    is "~0.2.6"
+
+octal@^1.0.0:
+  version "1.0.0"
+  resolved "https://registry.yarnpkg.com/octal/-/octal-1.0.0.tgz#63e7162a68efbeb9e213588d58e989d1e5c4530b"
+  integrity sha1-Y+cWKmjvvrniE1iNWOmJ0eXEUws=
+
+once@^1.3.0:
+  version "1.4.0"
+  resolved "https://registry.yarnpkg.com/once/-/once-1.4.0.tgz#583b1aa775961d4b113ac17d9c50baef9dd76bd1"
+  integrity sha1-WDsap3WWHUsROsF9nFC6753Xa9E=
+  dependencies:
+    wrappy "1"
+
+process-nextick-args@~2.0.0:
+  version "2.0.1"
+  resolved "https://registry.yarnpkg.com/process-nextick-args/-/process-nextick-args-2.0.1.tgz#7820d9b16120cc55ca9ae7792680ae7dba6d7fe2"
+  integrity sha512-3ouUOpQhtgrbOa17J7+uxOTpITYWaGP7/AhoR3+A+/1e9skrzelGi/dXzEYyvbxubEF6Wn2ypscTKiKJFFn1ag==
+
+prr@~1.0.1:
+  version "1.0.1"
+  resolved "https://registry.yarnpkg.com/prr/-/prr-1.0.1.tgz#d3fc114ba06995a45ec6893f484ceb1d78f5f476"
+  integrity sha1-0/wRS6BplaRexok/SEzrHXj19HY=
+
+readable-stream@^1.0.26-4:
+  version "1.1.14"
+  resolved "https://registry.yarnpkg.com/readable-stream/-/readable-stream-1.1.14.tgz#7cf4c54ef648e3813084c636dd2079e166c081d9"
+  integrity sha1-fPTFTvZI44EwhMY23SB54WbAgdk=
+  dependencies:
+    core-util-is "~1.0.0"
+    inherits "~2.0.1"
+    isarray "0.0.1"
+    string_decoder "~0.10.x"
+
+readable-stream@^2.2.2:
+  version "2.3.6"
+  resolved "https://registry.yarnpkg.com/readable-stream/-/readable-stream-2.3.6.tgz#b11c27d88b8ff1fbe070643cf94b0c79ae1b0aaf"
+  integrity sha512-tQtKA9WIAhBF3+VLAseyMqZeBjW0AHJoxOtYqSUZNJxauErmLbVm2FW1y+J/YA9dUrAC39ITejlZWhVIwawkKw==
+  dependencies:
+    core-util-is "~1.0.0"
+    inherits "~2.0.3"
+    isarray "~1.0.0"
+    process-nextick-args "~2.0.0"
+    safe-buffer "~5.1.1"
+    string_decoder "~1.1.1"
+    util-deprecate "~1.0.1"
+
+readable-stream@^3.0.2:
+  version "3.4.0"
+  resolved "https://registry.yarnpkg.com/readable-stream/-/readable-stream-3.4.0.tgz#a51c26754658e0a3c21dbf59163bd45ba6f447fc"
+  integrity sha512-jItXPLmrSR8jmTRmRWJXCnGJsfy85mB3Wd/uINMXA65yrnFo0cPClFIUWzo2najVNSl+mx7/4W8ttlLWJe99pQ==
+  dependencies:
+    inherits "^2.0.3"
+    string_decoder "^1.1.1"
+    util-deprecate "^1.0.1"
+
+readable-stream@~1.0.26-4:
+  version "1.0.34"
+  resolved "https://registry.yarnpkg.com/readable-stream/-/readable-stream-1.0.34.tgz#125820e34bc842d2f2aaafafe4c2916ee32c157c"
+  integrity sha1-Elgg40vIQtLyqq+v5MKRbuMsFXw=
+  dependencies:
+    core-util-is "~1.0.0"
+    inherits "~2.0.1"
+    isarray "0.0.1"
+    string_decoder "~0.10.x"
+
+safe-buffer@~5.1.0, safe-buffer@~5.1.1:
+  version "5.1.2"
+  resolved "https://registry.yarnpkg.com/safe-buffer/-/safe-buffer-5.1.2.tgz#991ec69d296e0313747d59bdfd2b745c35f8828d"
+  integrity sha512-Gd2UZBJDkXlY7GbJxfsE8/nvKkUEU1G38c1siN6QP6a9PT9MmHB8GnpscSmMJSoF8LOIrt8ud/wPtojys4G6+g==
+
+string-range@~1.2, string-range@~1.2.1:
+  version "1.2.2"
+  resolved "https://registry.yarnpkg.com/string-range/-/string-range-1.2.2.tgz#a893ed347e72299bc83befbbf2a692a8d239d5dd"
+  integrity sha1-qJPtNH5yKZvIO++78qaSqNI51d0=
+
+string_decoder@^1.1.1:
+  version "1.2.0"
+  resolved "https://registry.yarnpkg.com/string_decoder/-/string_decoder-1.2.0.tgz#fe86e738b19544afe70469243b2a1ee9240eae8d"
+  integrity sha512-6YqyX6ZWEYguAxgZzHGL7SsCeGx3V2TtOTqZz1xSTSWnqsbWwbptafNyvf/ACquZUXV3DANr5BDIwNYe1mN42w==
+  dependencies:
+    safe-buffer "~5.1.0"
+
+string_decoder@~0.10.x:
+  version "0.10.31"
+  resolved "https://registry.yarnpkg.com/string_decoder/-/string_decoder-0.10.31.tgz#62e203bc41766c6c28c9fc84301dab1c5310fa94"
+  integrity sha1-YuIDvEF2bGwoyfyEMB2rHFMQ+pQ=
+
+string_decoder@~1.1.1:
+  version "1.1.1"
+  resolved "https://registry.yarnpkg.com/string_decoder/-/string_decoder-1.1.1.tgz#9cf1611ba62685d7030ae9e4ba34149c3af03fc8"
+  integrity sha512-n/ShnvDi6FHbbVfviro+WojiFzv+s8MPMHBczVePfUpDJLwoLT0ht1l4YwBCbi8pJAveEEdnkHyPyTP/mzRfwg==
+  dependencies:
+    safe-buffer "~5.1.0"
+
+typedarray@^0.0.6:
+  version "0.0.6"
+  resolved "https://registry.yarnpkg.com/typedarray/-/typedarray-0.0.6.tgz#867ac74e3864187b1d3d47d996a78ec5c8830777"
+  integrity sha1-hnrHTjhkGHsdPUfZlqeOxciDB3c=
+
+util-deprecate@^1.0.1, util-deprecate@~1.0.1:
+  version "1.0.2"
+  resolved "https://registry.yarnpkg.com/util-deprecate/-/util-deprecate-1.0.2.tgz#450d4dc9fa70de732762fbd2d4a28981419a0ccf"
+  integrity sha1-RQ1Nyfpw3nMnYvvS1KKJgUGaDM8=
+
+wrappy@1:
+  version "1.0.2"
+  resolved "https://registry.yarnpkg.com/wrappy/-/wrappy-1.0.2.tgz#b5243d8f3ec1aa35f1364605bc0d1036e30ab69f"
+  integrity sha1-tSQ9jz7BqjXxNkYFvA0QNuMKtp8=
+
+xtend@^2.2.0:
+  version "2.2.0"
+  resolved "https://registry.yarnpkg.com/xtend/-/xtend-2.2.0.tgz#eef6b1f198c1c8deafad8b1765a04dad4a01c5a9"
+  integrity sha1-7vax8ZjByN6vrYsXZaBNrUoBxak=
+
+xtend@^4.0.0, xtend@~4.0.0:
+  version "4.0.2"
+  resolved "https://registry.yarnpkg.com/xtend/-/xtend-4.0.2.tgz#bb72779f5fa465186b1f438f674fa347fdb5db54"
+  integrity sha512-LKYU1iAXJXUgAXn9URjiu+MWhyUXHsvfp7mcuYm9dSUKK0/CjtrUwFAxD82/mCWbtLsGjFIad0wIsod4zrTAEQ==
+
+xtend@~2.0.4:
+  version "2.0.6"
+  resolved "https://registry.yarnpkg.com/xtend/-/xtend-2.0.6.tgz#5ea657a6dba447069c2e59c58a1138cb0c5e6cee"
+  integrity sha1-XqZXptukRwacLlnFihE4ywxebO4=
+  dependencies:
+    is-object "~0.1.2"
+    object-keys "~0.2.0"