diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index 24874bf7..e2a308d9 100644
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -1,10 +1,16 @@
-name: Build
+name: Build Check
 
 on:
   push:
-    branches: [ master ]
+    branches:
+      - master
+      - develop
+      - 'v[0-9]+.[0-9]+'
   pull_request:
-    branches: [ master ]
+    branches:
+      - master
+      - develop
+      - 'v[0-9]+.[0-9]+'
 
 env:
   CARGO_TERM_COLOR: always
@@ -13,13 +19,14 @@ jobs:
   default:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@v4
+      # NOTE: Dont use nix here, everything should be based on the ubuntu-latest
       - name: Install rust stable
         uses: actions-rs/toolchain@v1
         with:
           toolchain: stable
           override: true
-      - name: Default build
+      - name: Latest Ubuntu build check
         uses: actions-rs/cargo@v1
         with:
           command: check
@@ -33,22 +40,13 @@ jobs:
           - fs
           - serde
     steps:
-      - uses: actions/checkout@v2
-      - name: Install rust stable
-        uses: actions-rs/toolchain@v1
-        with:
-          toolchain: stable
-          override: true
-      - name: Feature ${{ matrix.feature }}
-        uses: actions-rs/cargo@v1
-        with:
-          command: check
-          args: --no-default-features --features=${{ matrix.feature }}
-      - name: Defaults + ${{ matrix.feature }}
-        uses: actions-rs/cargo@v1
-        with:
-          command: check
-          args: --features=${{ matrix.feature }}
+      - uses: actions/checkout@v4
+      - name: Install Nix
+        uses: cachix/install-nix-action@v26
+      - name: Check feature ${{ matrix.feature }} only
+        run: nix develop .#stable -c cargo check --no-default-features --features=${{ matrix.feature }}
+      - name: Check feature ${{ matrix.feature }} with defaults
+        run: nix develop .#stable -c cargo check --features=${{ matrix.feature }}
   platforms:
     runs-on: ${{ matrix.os }}
     strategy:
@@ -56,13 +54,14 @@ jobs:
       matrix:
         os: [ ubuntu-20.04, ubuntu-22.04, macos-12, macos-13, windows-2019, windows-2022 ]
     steps:
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@v4
+      # NOTE: Dont use nix in platform checks everything should based on the host system
       - name: Install rust stable
         uses: actions-rs/toolchain@v1
         with:
           toolchain: stable
           override: true
-      - name: Build with all features
+      - name: Build check with all features
         uses: actions-rs/cargo@v1
         with:
           command: check
@@ -72,16 +71,11 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        toolchain: [ nightly, beta, stable, 1.75.0 ]
+        toolchain: [ nightly, beta, stable, msrv ]
     steps:
-      - uses: actions/checkout@v2
-      - name: Install rust ${{ matrix.toolchain }}
-        uses: actions-rs/toolchain@v1
-        with:
-          toolchain: ${{ matrix.toolchain }}
-          override: true
-      - name: All features
-        uses: actions-rs/cargo@v1
-        with:
-          command: check
-          args: --workspace --all-targets --all-features
+      - name: checkout
+        uses: actions/checkout@v4
+      - name: Install Nix
+        uses: cachix/install-nix-action@v26
+      - name: Check Crates
+        run: nix develop ".#${{ matrix.toolchain }}" -c cargo check --workspace --all-targets --all-features
diff --git a/.github/workflows/codecov.yml b/.github/workflows/codecov.yml
index 20773195..4a23e91b 100644
--- a/.github/workflows/codecov.yml
+++ b/.github/workflows/codecov.yml
@@ -2,9 +2,15 @@ name: Codecov
 
 on:
   push:
-    branches: [ master ]
+    branches:
+      - master
+      - develop
+      - 'v[0-9]+.[0-9]+'
   pull_request:
-    branches: [ master ]
+    branches:
+      - master
+      - develop
+      - 'v[0-9]+.[0-9]+'
 
 env:
   CARGO_TERM_COLOR: always
@@ -14,38 +20,22 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v2
-      - name: Set up toolchain
-        uses: actions-rs/toolchain@v1
-        with:
-          profile: minimal
-          toolchain: stable
-          override: true
-          components: rustfmt, llvm-tools-preview
+      - name: Install Nix
+        uses: cachix/install-nix-action@v26
       - name: Build
-        uses: actions-rs/cargo@v1
-        with:
-          command: build
-          args: --release
-        env:
-          CARGO_INCREMENTAL: "0"
-          RUSTFLAGS: "-Cinstrument-coverage"
-          RUSTDOCFLAGS: "-Cinstrument-coverage"
+        run: nix develop .#codecov -c cargo build --release
       - name: Test
-        uses: actions-rs/cargo@v1
-        with:
-          command: test
-          args: --all-features --no-fail-fast
-        env:
-          CARGO_INCREMENTAL: "0"
-          RUSTFLAGS: "-Cinstrument-coverage"
-          RUSTDOCFLAGS: "-Cinstrument-coverage"
+        run: nix develop .#codecov -c cargo test --all-features --no-fail-fast --tests
       - name: Install grcov
-        run: if [[ ! -e ~/.cargo/bin/grcov ]]; then cargo install grcov; fi
+        run: nix develop .#codecov -c cargo install grcov
       - name: Generate coverage
-        run: grcov . --binary-path target/debug/deps/ -s . -t lcov --branch --ignore-not-existing --ignore '../**' --ignore '/*' -o coverage.lcov
+        run: nix develop .#codecov -c grcov . --binary-path target/debug/deps/ -s . -t lcov --branch --ignore-not-existing --ignore '../**' --ignore '/*' -o coverage.lcov
       - name: Upload coverage to Codecov
-        uses: codecov/codecov-action@v3
+        uses: codecov/codecov-action@v4
         with:
           files: ./coverage.lcov
           flags: rust
-          fail_ci_if_error: true
+          # TODO: set true when CODECOV_TOKEN is set
+          fail_ci_if_error: false
+        env:
+          CODECOV_TOKEN: ${{ secrets.CODECOV_TOKEN }}
diff --git a/.github/workflows/lint.yml b/.github/workflows/lint.yml
index 3f51bde0..7ca82979 100644
--- a/.github/workflows/lint.yml
+++ b/.github/workflows/lint.yml
@@ -2,9 +2,15 @@ name: Lints
 
 on:
   push:
-    branches: [ master ]
+    branches:
+      - master
+      - develop
+      - 'v[0-9]+.[0-9]+'
   pull_request:
-    branches: [ master ]
+    branches:
+      - master
+      - develop
+      - 'v[0-9]+.[0-9]+'
 
 env:
   CARGO_TERM_COLOR: always
@@ -13,45 +19,24 @@ jobs:
   fmt:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v2
-      - name: Install rustc nightly
-        uses: actions-rs/toolchain@v1
-        with:
-          toolchain: nightly
-          override: true
-          components: rustfmt
-      - uses: actions-rs/cargo@v1
-        name: Formatting
-        with:
-          command: fmt
-          args: --all -- --check
+      - uses: actions/checkout@v4
+      - name: Install Nix
+        uses: cachix/install-nix-action@v26
+      - name: Formatting
+        run: nix develop .#nightly -c cargo fmt --all -- --check
   clippy:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v2
-      - name: Install rustc stable
-        uses: actions-rs/toolchain@v1
-        with:
-          toolchain: stable
-          override: true
-          components: clippy
-      - uses: actions-rs/cargo@v1
-        name: Clippy
-        with:
-          command: clippy
-          args: --workspace --all-features --all-targets -- -D warnings
+      - uses: actions/checkout@v4
+      - name: Install Nix
+        uses: cachix/install-nix-action@v26
+      - name: Clippy
+        run: nix develop .#stable -c cargo clippy --workspace --all-features --all-targets -- -D warnings
   doc:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v2
-      - name: Install rustc nightly
-        uses: actions-rs/toolchain@v1
-        with:
-          toolchain: nightly
-          override: true
-          components: rust-docs
-      - uses: actions-rs/cargo@v1
-        name: Doc
-        with:
-          command: doc
-          args: --workspace --all-features
+      - uses: actions/checkout@v4
+      - name: Install Nix
+        uses: cachix/install-nix-action@v26
+      - name: Doc
+        run: nix develop .#nightly -c cargo doc --workspace --all-features
diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index f40b2cd0..1dae2740 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -2,9 +2,15 @@ name: Tests
 
 on:
   push:
-    branches: [ master ]
+    branches:
+      - master
+      - develop
+      - 'v[0-9]+.[0-9]+'
   pull_request:
-    branches: [ master ]
+    branches:
+      - master
+      - develop
+      - 'v[0-9]+.[0-9]+'
 
 env:
   CARGO_TERM_COLOR: always
@@ -13,29 +19,16 @@ jobs:
   testing:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v2
-      - name: Install latest stable
-        uses: actions-rs/toolchain@v1
-        with:
-          toolchain: stable
-          override: true
+      - uses: actions/checkout@v4
+      - name: Install Nix
+        uses: cachix/install-nix-action@v26
       - name: Build & test
-        uses: actions-rs/cargo@v1
-        with:
-          command: test
-          args: --workspace --all-features --no-fail-fast
+        run: nix develop .#stable -c cargo test --workspace --all-features --no-fail-fast --tests
   wasm-testing:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v2
-      - name: Install rust nightly
-        uses: actions-rs/toolchain@v1
-        with:
-          toolchain: nightly
-          override: true
-      - uses: Swatinem/rust-cache@v2
-      - uses: jetli/wasm-pack-action@v0.3.0
-      - name: Add wasm32 target
-        run: rustup target add wasm32-unknown-unknown
+      - uses: actions/checkout@v4
+      - name: Install Nix
+        uses: cachix/install-nix-action@v26
       - name: Test in headless Chrome
-        run: wasm-pack test --headless --chrome
+        run: nix develop .#wasm -c wasm-pack test --headless --chrome
diff --git a/.gitignore b/.gitignore
index e8ab911e..2f2af66b 100644
--- a/.gitignore
+++ b/.gitignore
@@ -10,3 +10,6 @@
 *.swp
 
 /dep_test
+result
+default_*.profraw
+coverage.lcov
diff --git a/README.md b/README.md
index cd72d957..7e26ed0b 100644
--- a/README.md
+++ b/README.md
@@ -56,7 +56,7 @@ by default.
 
 ### MSRV
 
-Minimum supported rust compiler version (MSRV): 1.66, rust 2021 edition.
+Minimum supported rust compiler version (MSRV) is shown in `rust-version` of `Cargo.toml`.
 
 ## Contributing
 
diff --git a/flake.lock b/flake.lock
new file mode 100644
index 00000000..6894ac04
--- /dev/null
+++ b/flake.lock
@@ -0,0 +1,85 @@
+{
+  "nodes": {
+    "flake-utils": {
+      "inputs": {
+        "systems": "systems"
+      },
+      "locked": {
+        "lastModified": 1710146030,
+        "narHash": "sha256-SZ5L6eA7HJ/nmkzGG7/ISclqe6oZdOZTNoesiInkXPQ=",
+        "owner": "numtide",
+        "repo": "flake-utils",
+        "rev": "b1d9ab70662946ef0850d488da1c9019f3a9752a",
+        "type": "github"
+      },
+      "original": {
+        "owner": "numtide",
+        "repo": "flake-utils",
+        "type": "github"
+      }
+    },
+    "nixpkgs": {
+      "locked": {
+        "lastModified": 1712439257,
+        "narHash": "sha256-aSpiNepFOMk9932HOax0XwNxbA38GOUVOiXfUVPOrck=",
+        "owner": "nixos",
+        "repo": "nixpkgs",
+        "rev": "ff0dbd94265ac470dda06a657d5fe49de93b4599",
+        "type": "github"
+      },
+      "original": {
+        "owner": "nixos",
+        "ref": "nixos-unstable",
+        "repo": "nixpkgs",
+        "type": "github"
+      }
+    },
+    "root": {
+      "inputs": {
+        "flake-utils": "flake-utils",
+        "nixpkgs": "nixpkgs",
+        "rust-overlay": "rust-overlay"
+      }
+    },
+    "rust-overlay": {
+      "inputs": {
+        "flake-utils": [
+          "flake-utils"
+        ],
+        "nixpkgs": [
+          "nixpkgs"
+        ]
+      },
+      "locked": {
+        "lastModified": 1712542394,
+        "narHash": "sha256-UZebDBECRSrJqw4K+LxZ6qFdYnScu6q1XCwqtsu1cas=",
+        "owner": "oxalica",
+        "repo": "rust-overlay",
+        "rev": "ece8bdb3c3b58def25f204b9a1261dee55d7c9c0",
+        "type": "github"
+      },
+      "original": {
+        "owner": "oxalica",
+        "repo": "rust-overlay",
+        "type": "github"
+      }
+    },
+    "systems": {
+      "locked": {
+        "lastModified": 1681028828,
+        "narHash": "sha256-Vy1rq5AaRuLzOxct8nz4T6wlgyUR7zLU309k9mBC768=",
+        "owner": "nix-systems",
+        "repo": "default",
+        "rev": "da67096a3b9bf56a91d16901293e51ba5b49a27e",
+        "type": "github"
+      },
+      "original": {
+        "owner": "nix-systems",
+        "repo": "default",
+        "type": "github"
+      }
+    }
+  },
+  "root": "root",
+  "version": 7
+}
diff --git a/flake.nix b/flake.nix
new file mode 100644
index 00000000..97a9cc3d
--- /dev/null
+++ b/flake.nix
@@ -0,0 +1,80 @@
+{
+  inputs = {
+    nixpkgs.url = "github:nixos/nixpkgs/nixos-unstable";
+    rust-overlay = {
+      url = "github:oxalica/rust-overlay";
+      inputs.nixpkgs.follows = "nixpkgs";
+      inputs.flake-utils.follows = "flake-utils";
+    };
+    flake-utils.url = "github:numtide/flake-utils";
+  };
+
+  outputs = { self, rust-overlay, nixpkgs, flake-utils }:
+    flake-utils.lib.eachDefaultSystem (system:
+      let
+        overlays = [ (import rust-overlay) ];
+        pkgs = import nixpkgs {
+          inherit system overlays;
+        };
+
+        cargoToml = builtins.fromTOML (builtins.readFile ./Cargo.toml);
+
+        nightlyWithWasm = pkgs.rust-bin.nightly.latest.default.override {
+          extensions = [ ];
+          targets = [ "wasm32-unknown-unknown" ];
+        };
+
+        stableWithLlvm = pkgs.rust-bin.nightly.latest.default.override {
+          extensions = [ "rustfmt" "llvm-tools-preview" ];
+          targets = [ ];
+        };
+      in
+      with pkgs;
+      {
+        devShells = rec {
+          default = msrv;
+
+          msrv = mkShell {
+            buildInputs = [
+              rust-bin.stable."${cargoToml.workspace.package."rust-version"}".default
+            ];
+          };
+
+          stable = mkShell {
+            buildInputs = [
+              rust-bin.stable.latest.default
+            ];
+          };
+
+          beta = mkShell {
+            buildInputs = [
+              rust-bin.beta.latest.default
+            ];
+          };
+
+          nightly = mkShell {
+            buildInputs = [
+              rust-bin.nightly.latest.default
+            ];
+          };
+
+          wasm = mkShell {
+            buildInputs = [
+              nightlyWithWasm
+              chromedriver
+              wasm-pack
+            ];
+          };
+
+          codecov = mkShell {
+            buildInputs = [
+              stableWithLlvm
+            ];
+            CARGO_INCREMENTAL = "0";
+            RUSTFLAGS = "-Cinstrument-coverage";
+            RUSTDOCFLAGS = "-Cinstrument-coverage";
+          };
+        };
+      }
+    );
+}