diff --git a/.github/workflows/cd.yml b/.github/workflows/cd.yml
index a5474f3..d289e58 100644
--- a/.github/workflows/cd.yml
+++ b/.github/workflows/cd.yml
@@ -13,7 +13,7 @@ jobs:
           python-version: "3.10"
       - uses: abatilo/actions-poetry@v2.0.0
         with:
-            poetry-version: 1.1.11
+            poetry-version: 1.1.13
       - name: Upload to pypi
         run: |
           poetry build
diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index ca43b11..e0d0f87 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -13,7 +13,7 @@ jobs:
     strategy:
       matrix:
         os: [ubuntu-latest, macos-latest, windows-latest]
-        python-version: ["3.6", "3.7", "3.8", "3.9", "3.10"]
+        python-version: ["3.7", "3.8", "3.9", "3.10"]
     steps:
       - uses: actions/checkout@v2
       - uses: actions/setup-python@v2
@@ -21,16 +21,20 @@ jobs:
           python-version: ${{ matrix.python-version }}
       - uses: abatilo/actions-poetry@v2.0.0
         with:
-            poetry-version: 1.1.11
+            poetry-version: 1.1.13
       - uses: actions/cache@v2
         with:
           path: |
             ~/.cache/pypoetry/virtualenvs
           key: ${{ runner.os }}-${{ matrix.python-version }}-poetry-${{ hashFiles('**/poetry.lock') }}
+
       - run: brew install automake
         if: matrix.os == 'macos-latest'
+
       - run: poetry install --no-dev
-      - name: Run test
-        run: |
-          ./scripts/ci.sh
+
+      - run: ./scripts/ci.sh
+
+      - uses: codecov/codecov-action@v2
+
       - run: poetry build
diff --git a/poetry.lock b/poetry.lock
index 2624ddf..db3c4d7 100644
--- a/poetry.lock
+++ b/poetry.lock
@@ -1,6 +1,6 @@
 [[package]]
 name = "appnope"
-version = "0.1.2"
+version = "0.1.3"
 description = "Disable App Nap on macOS >= 10.9"
 category = "dev"
 optional = false
@@ -8,12 +8,26 @@ python-versions = "*"
 
 [[package]]
 name = "asn1crypto"
-version = "1.4.0"
+version = "1.5.1"
 description = "Fast ASN.1 parser and serializer with definitions for private keys, public keys, certificates, CRL, OCSP, CMS, PKCS#3, PKCS#7, PKCS#8, PKCS#12, PKCS#5, X.509 and TSP"
 category = "main"
 optional = false
 python-versions = "*"
 
+[[package]]
+name = "asttokens"
+version = "2.0.5"
+description = "Annotate AST trees with source code positions"
+category = "dev"
+optional = false
+python-versions = "*"
+
+[package.dependencies]
+six = "*"
+
+[package.extras]
+test = ["astroid", "pytest"]
+
 [[package]]
 name = "backcall"
 version = "0.2.0"
@@ -32,7 +46,6 @@ python-versions = ">=3.6.2"
 
 [package.dependencies]
 click = ">=8.0.0"
-dataclasses = {version = ">=0.6", markers = "python_version < \"3.7\""}
 mypy-extensions = ">=0.4.3"
 pathspec = ">=0.9.0"
 platformdirs = ">=2"
@@ -59,11 +72,11 @@ pycparser = "*"
 
 [[package]]
 name = "click"
-version = "8.0.3"
+version = "8.1.3"
 description = "Composable command line interface toolkit"
 category = "dev"
 optional = false
-python-versions = ">=3.6"
+python-versions = ">=3.7"
 
 [package.dependencies]
 colorama = {version = "*", markers = "platform_system == \"Windows\""}
@@ -103,17 +116,9 @@ toolz = ">=0.8.0"
 [package.extras]
 cython = ["cython"]
 
-[[package]]
-name = "dataclasses"
-version = "0.8"
-description = "A backport of the dataclasses module for Python 3.6"
-category = "dev"
-optional = false
-python-versions = ">=3.6, <3.7"
-
 [[package]]
 name = "decorator"
-version = "5.1.0"
+version = "5.1.1"
 description = "Decorators for Humans"
 category = "dev"
 optional = false
@@ -156,7 +161,7 @@ test = ["asn1tools (>=0.146.2,<0.147)", "factory-boy (>=3.0.1,<3.1)", "pyasn1 (>
 
 [[package]]
 name = "eth-typing"
-version = "2.2.2"
+version = "2.3.0"
 description = "eth-typing: Common type annotations for ethereum python packages"
 category = "main"
 optional = false
@@ -188,6 +193,14 @@ doc = ["Sphinx (>=1.6.5,<2)", "sphinx-rtd-theme (>=0.1.9,<2)", "towncrier (>=19.
 lint = ["black (>=18.6b4,<19)", "flake8 (==3.7.9)", "isort (>=4.2.15,<5)", "mypy (==0.720)", "pydocstyle (>=5.0.0,<6)", "pytest (>=3.4.1,<4.0.0)"]
 test = ["hypothesis (>=4.43.0,<5.0.0)", "pytest (==5.4.1)", "pytest-xdist", "tox (==3.14.6)"]
 
+[[package]]
+name = "executing"
+version = "0.8.3"
+description = "Get the currently executing AST node of a frame, and other information"
+category = "dev"
+optional = false
+python-versions = "*"
+
 [[package]]
 name = "flake8"
 version = "4.0.1"
@@ -220,11 +233,11 @@ testing = ["pytest (>=4.6)", "pytest-checkdocs (>=2.4)", "pytest-flake8", "pytes
 
 [[package]]
 name = "ipython"
-version = "7.33.0"
+version = "8.4.0"
 description = "IPython: Productive Interactive Computing"
 category = "dev"
 optional = false
-python-versions = ">=3.7"
+python-versions = ">=3.8"
 
 [package.dependencies]
 appnope = {version = "*", markers = "sys_platform == \"darwin\""}
@@ -236,23 +249,26 @@ matplotlib-inline = "*"
 pexpect = {version = ">4.3", markers = "sys_platform != \"win32\""}
 pickleshare = "*"
 prompt-toolkit = ">=2.0.0,<3.0.0 || >3.0.0,<3.0.1 || >3.0.1,<3.1.0"
-pygments = "*"
-traitlets = ">=4.2"
+pygments = ">=2.4.0"
+stack-data = "*"
+traitlets = ">=5"
 
 [package.extras]
-all = ["Sphinx (>=1.3)", "ipykernel", "ipyparallel", "ipywidgets", "nbconvert", "nbformat", "nose (>=0.10.1)", "notebook", "numpy (>=1.17)", "pygments", "qtconsole", "requests", "testpath"]
+all = ["black", "Sphinx (>=1.3)", "ipykernel", "nbconvert", "nbformat", "ipywidgets", "notebook", "ipyparallel", "qtconsole", "pytest (<7.1)", "pytest-asyncio", "testpath", "curio", "matplotlib (!=3.2.0)", "numpy (>=1.19)", "pandas", "trio"]
+black = ["black"]
 doc = ["Sphinx (>=1.3)"]
 kernel = ["ipykernel"]
 nbconvert = ["nbconvert"]
 nbformat = ["nbformat"]
-notebook = ["notebook", "ipywidgets"]
+notebook = ["ipywidgets", "notebook"]
 parallel = ["ipyparallel"]
 qtconsole = ["qtconsole"]
-test = ["nose (>=0.10.1)", "requests", "testpath", "pygments", "nbformat", "ipykernel", "numpy (>=1.17)"]
+test = ["pytest (<7.1)", "pytest-asyncio", "testpath"]
+test_extra = ["pytest (<7.1)", "pytest-asyncio", "testpath", "curio", "matplotlib (!=3.2.0)", "nbformat", "numpy (>=1.19)", "pandas", "trio"]
 
 [[package]]
 name = "jedi"
-version = "0.18.0"
+version = "0.18.1"
 description = "An autocompletion tool for Python that can be used for text editors."
 category = "dev"
 optional = false
@@ -263,7 +279,7 @@ parso = ">=0.8.0,<0.9.0"
 
 [package.extras]
 qa = ["flake8 (==3.8.3)", "mypy (==0.782)"]
-testing = ["Django (<3.1)", "colorama", "docopt", "pytest (<6.0.0)"]
+testing = ["Django (<3.1)", "colorama", "docopt", "pytest (<7.0.0)"]
 
 [[package]]
 name = "matplotlib-inline"
@@ -313,7 +329,7 @@ python-versions = "*"
 
 [[package]]
 name = "parso"
-version = "0.8.2"
+version = "0.8.3"
 description = "A Python Parser"
 category = "dev"
 optional = false
@@ -352,19 +368,19 @@ python-versions = "*"
 
 [[package]]
 name = "platformdirs"
-version = "2.4.0"
+version = "2.5.2"
 description = "A small Python module for determining appropriate platform-specific dirs, e.g. a \"user data dir\"."
 category = "dev"
 optional = false
-python-versions = ">=3.6"
+python-versions = ">=3.7"
 
 [package.extras]
-docs = ["Sphinx (>=4)", "furo (>=2021.7.5b38)", "proselint (>=0.10.2)", "sphinx-autodoc-typehints (>=1.12)"]
-test = ["appdirs (==1.4.4)", "pytest (>=6)", "pytest-cov (>=2.7)", "pytest-mock (>=3.6)"]
+docs = ["furo (>=2021.7.5b38)", "proselint (>=0.10.2)", "sphinx-autodoc-typehints (>=1.12)", "sphinx (>=4)"]
+test = ["appdirs (==1.4.4)", "pytest-cov (>=2.7)", "pytest-mock (>=3.6)", "pytest (>=6)"]
 
 [[package]]
 name = "prompt-toolkit"
-version = "3.0.22"
+version = "3.0.29"
 description = "Library for building powerful interactive command lines in Python"
 category = "dev"
 optional = false
@@ -381,6 +397,17 @@ category = "dev"
 optional = false
 python-versions = "*"
 
+[[package]]
+name = "pure-eval"
+version = "0.2.2"
+description = "Safely evaluate AST nodes without side effects"
+category = "dev"
+optional = false
+python-versions = "*"
+
+[package.extras]
+tests = ["pytest"]
+
 [[package]]
 name = "pycodestyle"
 version = "2.8.0"
@@ -415,19 +442,43 @@ python-versions = ">=2.7, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*"
 
 [[package]]
 name = "pygments"
-version = "2.10.0"
+version = "2.12.0"
 description = "Pygments is a syntax highlighting package written in Python."
 category = "dev"
 optional = false
-python-versions = ">=3.5"
+python-versions = ">=3.6"
+
+[[package]]
+name = "six"
+version = "1.16.0"
+description = "Python 2 and 3 compatibility utilities"
+category = "dev"
+optional = false
+python-versions = ">=2.7, !=3.0.*, !=3.1.*, !=3.2.*"
+
+[[package]]
+name = "stack-data"
+version = "0.2.0"
+description = "Extract data from python stack frames and tracebacks for informative displays"
+category = "dev"
+optional = false
+python-versions = "*"
+
+[package.dependencies]
+asttokens = "*"
+executing = "*"
+pure-eval = "*"
+
+[package.extras]
+tests = ["pytest", "typeguard", "pygments", "littleutils", "cython"]
 
 [[package]]
 name = "tomli"
-version = "1.2.2"
+version = "2.0.1"
 description = "A lil' TOML parser"
 category = "dev"
 optional = false
-python-versions = ">=3.6"
+python-versions = ">=3.7"
 
 [[package]]
 name = "toolz"
@@ -439,30 +490,30 @@ python-versions = ">=3.5"
 
 [[package]]
 name = "traitlets"
-version = "5.1.1"
-description = "Traitlets Python configuration system"
+version = "5.2.1.post0"
+description = ""
 category = "dev"
 optional = false
 python-versions = ">=3.7"
 
 [package.extras]
-test = ["pytest"]
+test = ["pre-commit", "pytest"]
 
 [[package]]
 name = "typed-ast"
-version = "1.4.3"
+version = "1.5.4"
 description = "a fork of Python 2 and 3 ast modules with type comment support"
 category = "dev"
 optional = false
-python-versions = "*"
+python-versions = ">=3.6"
 
 [[package]]
 name = "typing-extensions"
-version = "3.10.0.2"
-description = "Backported and Experimental Type Hints for Python 3.5+"
+version = "4.2.0"
+description = "Backported and Experimental Type Hints for Python 3.7+"
 category = "dev"
 optional = false
-python-versions = "*"
+python-versions = ">=3.7"
 
 [[package]]
 name = "wcwidth"
@@ -474,29 +525,33 @@ python-versions = "*"
 
 [[package]]
 name = "zipp"
-version = "3.6.0"
+version = "3.8.0"
 description = "Backport of pathlib-compatible object wrapper for zip files"
 category = "dev"
 optional = false
-python-versions = ">=3.6"
+python-versions = ">=3.7"
 
 [package.extras]
-docs = ["sphinx", "jaraco.packaging (>=8.2)", "rst.linker (>=1.9)"]
-testing = ["pytest (>=4.6)", "pytest-checkdocs (>=2.4)", "pytest-flake8", "pytest-cov", "pytest-enabler (>=1.0.1)", "jaraco.itertools", "func-timeout", "pytest-black (>=0.3.7)", "pytest-mypy"]
+docs = ["sphinx", "jaraco.packaging (>=9)", "rst.linker (>=1.9)"]
+testing = ["pytest (>=6)", "pytest-checkdocs (>=2.4)", "pytest-flake8", "pytest-cov", "pytest-enabler (>=1.0.1)", "jaraco.itertools", "func-timeout", "pytest-black (>=0.3.7)", "pytest-mypy (>=0.9.1)"]
 
 [metadata]
 lock-version = "1.1"
-python-versions = "^3.6"
-content-hash = "e1c43f90b302efd1022e12e4370dc716eebecb3c3a6c028052baecb65c03def4"
+python-versions = "^3.7"
+content-hash = "0c911cd310211151d8d170356893530fb4e5d91852b30efdfde7f4b412cf3519"
 
 [metadata.files]
 appnope = [
-    {file = "appnope-0.1.2-py2.py3-none-any.whl", hash = "sha256:93aa393e9d6c54c5cd570ccadd8edad61ea0c4b9ea7a01409020c9aa019eb442"},
-    {file = "appnope-0.1.2.tar.gz", hash = "sha256:dd83cd4b5b460958838f6eb3000c660b1f9caf2a5b1de4264e941512f603258a"},
+    {file = "appnope-0.1.3-py2.py3-none-any.whl", hash = "sha256:265a455292d0bd8a72453494fa24df5a11eb18373a60c7c0430889f22548605e"},
+    {file = "appnope-0.1.3.tar.gz", hash = "sha256:02bd91c4de869fbb1e1c50aafc4098827a7a54ab2f39d9dcba6c9547ed920e24"},
 ]
 asn1crypto = [
-    {file = "asn1crypto-1.4.0-py2.py3-none-any.whl", hash = "sha256:4bcdf33c861c7d40bdcd74d8e4dd7661aac320fcdf40b9a3f95b4ee12fde2fa8"},
-    {file = "asn1crypto-1.4.0.tar.gz", hash = "sha256:f4f6e119474e58e04a2b1af817eb585b4fd72bdd89b998624712b5c99be7641c"},
+    {file = "asn1crypto-1.5.1-py2.py3-none-any.whl", hash = "sha256:db4e40728b728508912cbb3d44f19ce188f218e9eba635821bb4b68564f8fd67"},
+    {file = "asn1crypto-1.5.1.tar.gz", hash = "sha256:13ae38502be632115abf8a24cbe5f4da52e3b5231990aff31123c805306ccb9c"},
+]
+asttokens = [
+    {file = "asttokens-2.0.5-py2.py3-none-any.whl", hash = "sha256:0844691e88552595a6f4a4281a9f7f79b8dd45ca4ccea82e5e05b4bbdb76705c"},
+    {file = "asttokens-2.0.5.tar.gz", hash = "sha256:9a54c114f02c7a9480d56550932546a3f1fe71d8a02f1bc7ccd0ee3ee35cf4d5"},
 ]
 backcall = [
     {file = "backcall-0.2.0-py2.py3-none-any.whl", hash = "sha256:fbbce6a29f263178a1f7915c1940bde0ec2b2a967566fe1c65c1dfb7422bd255"},
@@ -580,8 +635,8 @@ cffi = [
     {file = "cffi-1.15.0.tar.gz", hash = "sha256:920f0d66a896c2d99f0adbb391f990a84091179542c205fa53ce5787aff87954"},
 ]
 click = [
-    {file = "click-8.0.3-py3-none-any.whl", hash = "sha256:353f466495adaeb40b6b5f592f9f91cb22372351c84caeb068132442a4518ef3"},
-    {file = "click-8.0.3.tar.gz", hash = "sha256:410e932b050f5eed773c4cda94de75971c89cdb3155a72a0831139a79e5ecb5b"},
+    {file = "click-8.1.3-py3-none-any.whl", hash = "sha256:bb4d8133cb15a609f44e8213d9b391b0809795062913b383c62be0ee95b1db48"},
+    {file = "click-8.1.3.tar.gz", hash = "sha256:7682dc8afb30297001674575ea00d1814d808d6a36af415a82bd481d37ba7b8e"},
 ]
 coincurve = [
     {file = "coincurve-16.0.0-cp310-cp310-macosx_10_9_x86_64.whl", hash = "sha256:0df23cba832bea28bc0f35176b2aaa7585cc85decce9560b79ec4991d49e0901"},
@@ -637,13 +692,9 @@ colorama = [
 cytoolz = [
     {file = "cytoolz-0.11.2.tar.gz", hash = "sha256:ea23663153806edddce7e4153d1d407d62357c05120a4e8485bddf1bd5ab22b4"},
 ]
-dataclasses = [
-    {file = "dataclasses-0.8-py3-none-any.whl", hash = "sha256:0201d89fa866f68c8ebd9d08ee6ff50c0b255f8ec63a71c16fda7af82bb887bf"},
-    {file = "dataclasses-0.8.tar.gz", hash = "sha256:8479067f342acf957dc82ec415d355ab5edb7e7646b90dc6e2fd1d96ad084c97"},
-]
 decorator = [
-    {file = "decorator-5.1.0-py3-none-any.whl", hash = "sha256:7b12e7c3c6ab203a29e157335e9122cb03de9ab7264b137594103fd4a683b374"},
-    {file = "decorator-5.1.0.tar.gz", hash = "sha256:e59913af105b9860aa2c8d3272d9de5a56a4e608db9a2f167a8480b323d529a7"},
+    {file = "decorator-5.1.1-py3-none-any.whl", hash = "sha256:b8c3f85900b9dc423225913c5aace94729fe1fa9763b38939a95226f02d37186"},
+    {file = "decorator-5.1.1.tar.gz", hash = "sha256:637996211036b6385ef91435e4fae22989472f9d571faba8927ba8253acbc330"},
 ]
 eth-hash = [
     {file = "eth-hash-0.3.2.tar.gz", hash = "sha256:3f40cecd5ead88184aa9550afc19d057f103728108c5102f592f8415949b5a76"},
@@ -654,13 +705,17 @@ eth-keys = [
     {file = "eth_keys-0.3.4-py3-none-any.whl", hash = "sha256:565bf62179b8143bcbd302a0ec6c49882d9c7678f9e6ab0484a8a5725f5ef10e"},
 ]
 eth-typing = [
-    {file = "eth-typing-2.2.2.tar.gz", hash = "sha256:97ba0f83da7cf1d3668f6ed54983f21168076c552762bf5e06d4a20921877f3f"},
-    {file = "eth_typing-2.2.2-py3-none-any.whl", hash = "sha256:1140c7592321dbf10d6663c46f7e43eb0e6410b011b03f14b3df3eb1f76aa9bb"},
+    {file = "eth-typing-2.3.0.tar.gz", hash = "sha256:39cce97f401f082739b19258dfa3355101c64390914c73fe2b90012f443e0dc7"},
+    {file = "eth_typing-2.3.0-py3-none-any.whl", hash = "sha256:b7fa58635c1cb0cbf538b2f5f1e66139575ea4853eac1d6000f0961a4b277422"},
 ]
 eth-utils = [
     {file = "eth-utils-1.10.0.tar.gz", hash = "sha256:bf82762a46978714190b0370265a7148c954d3f0adaa31c6f085ea375e4c61af"},
     {file = "eth_utils-1.10.0-py3-none-any.whl", hash = "sha256:74240a8c6f652d085ed3c85f5f1654203d2f10ff9062f83b3bad0a12ff321c7a"},
 ]
+executing = [
+    {file = "executing-0.8.3-py2.py3-none-any.whl", hash = "sha256:d1eef132db1b83649a3905ca6dd8897f71ac6f8cac79a7e58a1a09cf137546c9"},
+    {file = "executing-0.8.3.tar.gz", hash = "sha256:c6554e21c6b060590a6d3be4b82fb78f8f0194d809de5ea7df1c093763311501"},
+]
 flake8 = [
     {file = "flake8-4.0.1-py2.py3-none-any.whl", hash = "sha256:479b1304f72536a55948cb40a32dce8bb0ffe3501e26eaf292c7e60eb5e0428d"},
     {file = "flake8-4.0.1.tar.gz", hash = "sha256:806e034dda44114815e23c16ef92f95c91e4c71100ff52813adf7132a6ad870d"},
@@ -670,12 +725,12 @@ importlib-metadata = [
     {file = "importlib_metadata-4.2.0.tar.gz", hash = "sha256:b7e52a1f8dec14a75ea73e0891f3060099ca1d8e6a462a4dff11c3e119ea1b31"},
 ]
 ipython = [
-    {file = "ipython-7.33.0-py3-none-any.whl", hash = "sha256:916a3126896e4fd78dd4d9cf3e21586e7fd93bae3f1cd751588b75524b64bf94"},
-    {file = "ipython-7.33.0.tar.gz", hash = "sha256:bcffb865a83b081620301ba0ec4d95084454f26b91d6d66b475bff3dfb0218d4"},
+    {file = "ipython-8.4.0-py3-none-any.whl", hash = "sha256:7ca74052a38fa25fe9bedf52da0be7d3fdd2fb027c3b778ea78dfe8c212937d1"},
+    {file = "ipython-8.4.0.tar.gz", hash = "sha256:f2db3a10254241d9b447232cec8b424847f338d9d36f9a577a6192c332a46abd"},
 ]
 jedi = [
-    {file = "jedi-0.18.0-py2.py3-none-any.whl", hash = "sha256:18456d83f65f400ab0c2d3319e48520420ef43b23a086fdc05dff34132f0fb93"},
-    {file = "jedi-0.18.0.tar.gz", hash = "sha256:92550a404bad8afed881a137ec9a461fed49eca661414be45059329614ed0707"},
+    {file = "jedi-0.18.1-py2.py3-none-any.whl", hash = "sha256:637c9635fcf47945ceb91cd7f320234a7be540ded6f3e99a50cb6febdfd1ba8d"},
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-    {file = "typing_extensions-3.10.0.2.tar.gz", hash = "sha256:49f75d16ff11f1cd258e1b988ccff82a3ca5570217d7ad8c5f48205dd99a677e"},
+    {file = "typing_extensions-4.2.0-py3-none-any.whl", hash = "sha256:6657594ee297170d19f67d55c05852a874e7eb634f4f753dbd667855e07c1708"},
+    {file = "typing_extensions-4.2.0.tar.gz", hash = "sha256:f1c24655a0da0d1b67f07e17a5e6b2a105894e6824b92096378bb3668ef02376"},
 ]
 wcwidth = [
     {file = "wcwidth-0.2.5-py2.py3-none-any.whl", hash = "sha256:beb4802a9cebb9144e99086eff703a642a13d6a0052920003a230f3294bbe784"},
     {file = "wcwidth-0.2.5.tar.gz", hash = "sha256:c4d647b99872929fdb7bdcaa4fbe7f01413ed3d98077df798530e5b04f116c83"},
 ]
 zipp = [
-    {file = "zipp-3.6.0-py3-none-any.whl", hash = "sha256:9fe5ea21568a0a70e50f273397638d39b03353731e6cbbb3fd8502a33fec40bc"},
-    {file = "zipp-3.6.0.tar.gz", hash = "sha256:71c644c5369f4a6e07636f0aa966270449561fcea2e3d6747b8d23efaa9d7832"},
+    {file = "zipp-3.8.0-py3-none-any.whl", hash = "sha256:c4f6e5bbf48e74f7a38e7cc5b0480ff42b0ae5178957d564d18932525d5cf099"},
+    {file = "zipp-3.8.0.tar.gz", hash = "sha256:56bf8aadb83c24db6c4b577e13de374ccfb67da2078beba1d037c17980bf43ad"},
 ]
diff --git a/pyproject.toml b/pyproject.toml
index b25b871..115e23d 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -3,7 +3,7 @@ name = "eciespy"
 packages = [
   {include = "ecies"},
 ]
-version = "0.3.11"
+version = "0.3.12"
 # docs
 authors = ["Weiliang Li <to.be.impressive@gmail.com>"]
 description = "Elliptic Curve Integrated Encryption Scheme for secp256k1 in Python"
@@ -33,16 +33,16 @@ keywords = [
 include = ["ecies/py.typed"]
 
 [tool.poetry.dependencies]
-python = "^3.6"
+python = "^3.7"
 # 3rd party
 coincurve = ">=13,<17"
 eth-keys = "^0.3.3"
 pycryptodome = "^3.9.9"
 
 [tool.poetry.dev-dependencies]
-black = {version = "^22.3", python = "^3.7"}
-flake8 = "^4.0"
-ipython = {version = "^7.33", python = "^3.7"}
+black = "^22.3"
+flake8 = "^4.0.1"
+ipython = {version = "^8.3.0", python = "^3.8"}
 mypy = "^0.960"
 
 [tool.poetry.scripts]
diff --git a/scripts/ci.sh b/scripts/ci.sh
index c13182c..6326586 100755
--- a/scripts/ci.sh
+++ b/scripts/ci.sh
@@ -1,12 +1,11 @@
 #!/bin/sh
 
 # test
-poetry run pip install codecov
+poetry run pip install coverage
 poetry run python -m doctest -v ecies/utils.py
 poetry run coverage run -m unittest discover .
 poetry run coverage report
 poetry run coverage xml
-poetry run codecov
 
 # test cli
 poetry run eciespy -h