diff --git a/.github/dependabot.yml b/.github/dependabot.yml
index b14e5af..672145d 100644
--- a/.github/dependabot.yml
+++ b/.github/dependabot.yml
@@ -17,10 +17,18 @@ updates:
     schedule:
       interval: "weekly"
   - package-ecosystem: "cargo"
-    directory: "/no-std-examples"
+    directory: "/examples/no-std-examples"
     schedule:
       interval: "weekly"
   - package-ecosystem: "cargo"
-    directory: "/complex-example"
+    directory: "/examples/complex-examples"
+    schedule:
+      interval: "weekly"
+  - package-ecosystem: "cargo"
+    directory: "/examples/patch-examples"
+    schedule:
+      interval: "weekly"
+  - package-ecosystem: "cargo"
+    directory: "/examples/filler-examples"
     schedule:
       interval: "weekly"
diff --git a/.github/workflows/lint.yml b/.github/workflows/lint.yml
index 8f994a1..7103cee 100644
--- a/.github/workflows/lint.yml
+++ b/.github/workflows/lint.yml
@@ -17,6 +17,9 @@ jobs:
         with:
           github_access_token: ${{ secrets.GITHUB_TOKEN }}
 
+      - name: Nix flake check
+        run: nix flake check
+
       - name: fmt
         run: nix develop .#ci -c cargo fmt
 
diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index 9bf0e4d..410a754 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -17,69 +17,33 @@ jobs:
         with:
           github_access_token: ${{ secrets.GITHUB_TOKEN }}
 
-      - name: Test no default features
+      - name: Build devshells
         run: |
-          nix develop .#ci -c cargo run --quiet --no-default-features --example instance
-          nix develop .#ci -c cargo run --quiet --no-default-features --example filler
-          nix develop .#ci -c cargo run --quiet --no-default-features --example diff
-          nix develop .#ci -c cargo run --quiet --no-default-features --example json
-          nix develop .#ci -c cargo run --quiet --no-default-features --example rename-patch-struct
-          nix develop .#ci -c cargo run --quiet --no-default-features --example patch-attr
-          nix develop .#ci -c cargo run --quiet --no-default-features --example time
-          nix develop .#ci -c cargo run --quiet --no-default-features --example clap
-          nix develop .#ci -c cargo run --quiet --no-default-features --features=nesting --example nesting
-          nix develop .#ci -c cargo run --quiet --no-default-features --features=option --example option
-          nix develop .#ci -c cargo run --quiet --no-default-features --example=log
-          nix develop .#ci -c cargo run --quiet --no-default-features --example apply-by
-          nix develop .#ci -c cargo run --quiet --no-default-features --features=box --example box
-          nix develop .#ci -c cargo test --quiet --no-default-features
+          nix develop .#ci -c echo Build ci devshell
+          nix develop .#no-std -c echo Build no-std devshell
 
-      - name: Test with std features
+      - name: Test lib
         run: |
-          nix develop .#ci -c cargo run --quiet --features=std --example instance
-          nix develop .#ci -c cargo run --quiet --features=std --example filler
-          nix develop .#ci -c cargo run --quiet --features=std --example filler-op
-          nix develop .#ci -c cargo run --quiet --features=std --example diff
-          nix develop .#ci -c cargo run --quiet --features=std --example json
-          nix develop .#ci -c cargo run --quiet --features=std --example rename-patch-struct
-          nix develop .#ci -c cargo run --quiet --features=std --example patch-attr
-          nix develop .#ci -c cargo run --quiet --features=std --example option
-          nix develop .#ci -c cargo run --quiet --features=std --example box
-          nix develop .#ci -c cargo run --quiet --features=std,nesting --example nesting
-          nix develop .#ci -c cargo test --quiet --features=std
+          nix develop .#ci -c test no-default
+          nix develop .#ci -c test std
+          nix develop .#ci -c test merge
+          nix develop .#ci -c test default
 
-      - name: Test with merge features
+      - name: Test patch examples
         run: |
-          nix develop .#ci -c cargo run --quiet --features=option,merge --example option
-          nix develop .#ci -c cargo run --quiet --features=merge --example op
-          nix develop .#ci -c cargo run --quiet --features=merge,nesting --example nesting
-          nix develop .#ci -c cargo test --quiet --features=merge --no-default-features
-          nix develop .#ci -c cargo test --quiet --features=merge
+          nix develop .#ci -c check-patch no-default
+          nix develop .#ci -c check-patch std
+          nix develop .#ci -c check-patch merge
+          nix develop .#ci -c check-patch option
+          nix develop .#ci -c check-patch default
 
-      - name: Test with option features
+      - name: Test filler examples
         run: |
-          nix develop .#ci -c cargo run --quiet --features=none_as_default --example option
-          nix develop .#ci -c cargo run --quiet --features=none_as_default,nesting --example nesting
-          nix develop .#ci -c cargo run --quiet --features=keep_none --example option
-          nix develop .#ci -c cargo run --quiet --features=keep_none,nesting --example nesting
-
-      - name: Test with default features
-        run: |
-          nix develop .#ci -c cargo run --quiet --example status
-          nix develop .#ci -c cargo run --quiet --example op
-          nix develop .#ci -c cargo run --quiet --example clap
-          nix develop .#ci -c cargo run --quiet --features=nesting --example nesting
-          nix develop .#ci -c cargo run --quiet --features=nesting --example clap
-          nix develop .#ci -c cargo run --quiet --example=log
-          nix develop .#ci -c cargo run --quiet --example apply-by
-          nix develop .#ci -c cargo run --quiet --features=box --example box
-          nix develop .#ci -c cargo test --quiet
+          nix develop .#ci -c check-filler no-default
+          nix develop .#ci -c check-filler default
 
       - name: Test in no std
-        run: |
-          cd no-std-examples
-          nix develop .#no-std -c cargo run --quiet --features=box --bin no-std-box
-          nix develop .#no-std -c cargo run --quiet --features=option --bin no-std-option
+        run: nix develop .#no-std -c check-no-std
 
-      - name: Test with catalyst
-        run: nix develop .#ci -c check-catalyst
+      - name: Test complex examples
+        run: nix develop .#ci -c check-complex
diff --git a/.gitignore b/.gitignore
index 1fa5e3d..3ed6912 100644
--- a/.gitignore
+++ b/.gitignore
@@ -3,5 +3,6 @@ Cargo.lock
 .envrc
 .direnv/
 struct-patch/examples
-no-std-examples/target
-complex-example/target
+examples/no-std-examples/target
+examples/complex-examples/target
+examples/patch-examples/target
diff --git a/Cargo.toml b/Cargo.toml
index f013e96..915ff03 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -5,8 +5,10 @@ members = [
     "derive",
 ]
 exclude = [
-    "no-std-examples",
-    "complex-example",
+    "examples/no-std-examples",
+    "examples/complex-examples",
+    "examples/patch-examples",
+    "examples/filler-examples",
 ]
 
 [workspace.package]
diff --git a/README.md b/README.md
index 29a65b9..8762a68 100644
--- a/README.md
+++ b/README.md
@@ -17,15 +17,15 @@ This crate provides the `Patch`, `Filler`, `Substrate`, `Catalyst` and `Complex`
 - If any field in the instance is empty (`None` or an empty collection), `Filler` will try to fill it. It supports `Option`, `Vec`, `VecDeque`, `LinkedList`, `HashMap`, `BTreeMap`, `HashSet`, `BTreeSet`, `BinaryHeap` fields, as well as custom types via `#[filler(extendable)]` and any type via `#[filler(empty_value = ...)]`.
 - With the `substrate` feature, the `Substrate` derive macro exposes field information so that other crates can access it. With the `catalyst` feature (which implies `substrate`), `Catalyst` and `Complex` derive macros help you extend a struct with extra fields from another crate.
 
-This crate supports `no_std` — check the [no-std-examples](./no-std-examples).
+This crate supports `no_std` — check the [no-std-examples](./examples/no-std-examples).
 
 The following are more specific scenarios to help you learn the details:
 - A project with config from environments, files, and command line: you can use `Patch` to keep your config organized. Please check this [template](https://github.com/yanganto/ConfigTemplate).
-- A project extended from another project, where only some fields of the config differ. You can use the `catalyst` feature to expose the base struct in a build script with `Substrate`, then a `Catalyst` struct can bind to it and produce a complex struct. Check the [complex-example](./complex-example) and [Quick Example: case 3](#case-3---extend-a-struct-from-a-crate).
+- A project extended from another project, where only some fields of the config differ. You can use the `catalyst` feature to expose the base struct in a build script with `Substrate`, then a `Catalyst` struct can bind to it and produce a complex struct. Check the [complex-examples](./examples/complex-examples) and [Quick Example: case 3](#case-3---extend-a-struct-from-a-crate).
 
 ## Quick Example
 
-#### Case 1 - Patch on a Config
+#### Case 1 (Patch) - Patch on a Config
 Deriving `Patch` on a struct generates a struct similar to the original one, but with all fields wrapped in an `Option`.
 An instance of such a patch struct can be applied onto the original struct, replacing values only if they are set to `Some`, leaving them unchanged otherwise.
 See also Case Studies: 
@@ -82,7 +82,7 @@ fn patch_json() {
 }
 ```
 
-#### Case 2 - Fill up on a Config
+#### Case 2 (Filler) - Fill up on a Config
 Deriving `Filler` on a struct generates a struct similar to the original one, keeping only the fields that can be filled (`Option`, collections, `extendable`, or `empty_value` fields). Unlike `Patch`, the `Filler` only works on empty fields of the instance.
 See also Case Studies: 
   - [Log which fields were patched or filled](docs/logs.md)
@@ -119,11 +119,11 @@ assert_eq!(item.maybe_field_int, Some(7));
 assert_eq!(item.list, vec![7]);
 ```
 
-#### Case 3 - Extend a struct from a crate
+#### Case 3 (Complex) - Extend a struct from a crate
 Deriving `Substrate` on a struct exposes the field information so that other crates can access it.
 Deriving `Catalyst` reads the field information of a `Substrate` and generates a new complex struct.
 In the other words, the catalyst is a struct with extra fields that the developer writes down in the downstream crate. The complex is a generated struct that combines the substrate's fields with the catalyst's extra fields. The overall behavior is like [chemical catalysts](https://en.wikipedia.org/wiki/Enzyme_catalysis): a catalyst **binds** onto a substrate to form a complex struct, which has all fields from both.
-A complex can also **decouple** without cloning, returning the original catalyst and substrate. Check the [complex-example](./complex-example/catalyst/src/lib.rs).
+A complex can also **decouple** without cloning, returning the original catalyst and substrate. Check the [complex-examples](./examples/complex-examples/catalyst/src/lib.rs).
 With the `unsafe` feature, `bind` and `decouple` use `ManuallyDrop` + `ptr::read` to avoid memory moves, and `__substrate_new` uses `MaybeUninit` + `ptr::write` while `__substrate_unpack` uses `ManuallyDrop` + `ptr::read`, such that the copy will be less.
 
 In terms of crate dependencies, the crate using `Substrate` is **upstream** (a dependency), and the crate using `Catalyst` is **downstream** (it depends on the substrate crate). There are two ways for the downstream crate to read the substrate's field layout:
@@ -165,7 +165,7 @@ struct Amyloid {
 // }
 ```
 
-**Option B: via source code with `src` attribute**: point the `Catalyst` macro directly at the substrate crate's source file using `#[catalyst(src = "crate_name:/path/to/file.rs")]`. The macro uses `cargo_metadata` to locate the package and `syn` to parse the file, so no `build.rs` or `expose()` call is required. Check the [catalyst-src example](./complex-example/catalyst-src/src/lib.rs).
+**Option B: via source code with `src` attribute**: point the `Catalyst` macro directly at the substrate crate's source file using `#[catalyst(src = "crate_name:/path/to/file.rs")]`. The macro uses `cargo_metadata` to locate the package and `syn` to parse the file, so no `build.rs` or `expose()` call is required. Check the [catalyst-src example](./examples/complex-examples/catalyst-src/src/lib.rs).
 
 ```rust
 /// In the substrate crate (src/lib.rs)
@@ -231,7 +231,9 @@ Please check the [traits documentation][doc-traits] to learn more.
 
 ## Examples
 
-The [examples][examples] demonstrate the following scenarios:
+Examples are organised into focused sub-projects under [`examples/`](./examples):
+
+**[patch-examples](./examples/patch-examples)** — `Patch` derive macro scenarios:
 - diff two instances for a patch (`diff.rs`)
 - create a patch from a JSON string (`json.rs`)
 - rename the patch structure (`rename-patch-struct.rs`)
@@ -241,14 +243,20 @@ The [examples][examples] demonstrate the following scenarios:
 - show operators on patches (`op.rs`)
 - show example with serde crates, e.g. `humantime_serde` for durations (`time.rs`)
 - show a patch nesting another patch (`nesting.rs`)
-- show filler with all possible types (`filler.rs`)
-- show operators on fillers (`filler-op.rs`)
 - show `skip_wrap` field behavior (`instance.rs`)
 - use `Patch` with `clap` for command-line config (`clap.rs`)
 - demonstrate `default_log` and `apply_with_log` for both `Patch` and `Filler` (`log.rs`)
 - apply a heap-allocated (boxed) patch and produce a boxed diff (`box.rs`)
 - demonstrate `apply_by` for custom field-level apply logic, e.g. list concatenation (`apply-by.rs`)
 
+**[filler-examples](./examples/filler-examples)** — `Filler` derive macro scenarios:
+- show filler with all possible types (`filler.rs`)
+- show operators on fillers (`filler-op.rs`)
+
+**[no-std-examples](./examples/no-std-examples)** — `no_std` usage with a bare-metal target.
+
+**[complex-examples](./examples/complex-examples)** — `Substrate` / `Catalyst` / `Complex` derive macros for extending a struct across crates.
+
 ## Features
 
 This crate includes the following optional features:
@@ -275,4 +283,4 @@ This crate includes the following optional features:
 [doc-badge]: https://img.shields.io/badge/docs-rs-orange.svg
 [doc-url]: https://docs.rs/struct-patch/
 [doc-traits]: https://docs.rs/struct-patch/latest/struct_patch/traits/trait.Patch.html#container-attributes
-[examples]: /lib/examples
+[examples]: /examples
diff --git a/complex-example/Cargo.toml b/examples/complex-examples/Cargo.toml
similarity index 93%
rename from complex-example/Cargo.toml
rename to examples/complex-examples/Cargo.toml
index 52cfb06..caa1747 100644
--- a/complex-example/Cargo.toml
+++ b/examples/complex-examples/Cargo.toml
@@ -6,7 +6,7 @@ members = [
     "catalyst-src",
 ]
 [workspace.dependencies]
-struct-patch = { path = "../lib" }
+struct-patch = { path = "../../lib" }
 
 [workspace.package]
 authors = ["Antonio Yang <yanganto@gmail.com>"]
diff --git a/complex-example/catalyst-src/Cargo.toml b/examples/complex-examples/catalyst-src/Cargo.toml
similarity index 100%
rename from complex-example/catalyst-src/Cargo.toml
rename to examples/complex-examples/catalyst-src/Cargo.toml
diff --git a/complex-example/catalyst-src/src/lib.rs b/examples/complex-examples/catalyst-src/src/lib.rs
similarity index 100%
rename from complex-example/catalyst-src/src/lib.rs
rename to examples/complex-examples/catalyst-src/src/lib.rs
diff --git a/complex-example/catalyst/Cargo.toml b/examples/complex-examples/catalyst/Cargo.toml
similarity index 100%
rename from complex-example/catalyst/Cargo.toml
rename to examples/complex-examples/catalyst/Cargo.toml
diff --git a/complex-example/catalyst/build.rs b/examples/complex-examples/catalyst/build.rs
similarity index 100%
rename from complex-example/catalyst/build.rs
rename to examples/complex-examples/catalyst/build.rs
diff --git a/complex-example/catalyst/src/lib.rs b/examples/complex-examples/catalyst/src/lib.rs
similarity index 100%
rename from complex-example/catalyst/src/lib.rs
rename to examples/complex-examples/catalyst/src/lib.rs
diff --git a/complex-example/substrate/Cargo.toml b/examples/complex-examples/substrate/Cargo.toml
similarity index 100%
rename from complex-example/substrate/Cargo.toml
rename to examples/complex-examples/substrate/Cargo.toml
diff --git a/complex-example/substrate/src/lib.rs b/examples/complex-examples/substrate/src/lib.rs
similarity index 100%
rename from complex-example/substrate/src/lib.rs
rename to examples/complex-examples/substrate/src/lib.rs
diff --git a/examples/filler-examples/Cargo.toml b/examples/filler-examples/Cargo.toml
new file mode 100644
index 0000000..07ae398
--- /dev/null
+++ b/examples/filler-examples/Cargo.toml
@@ -0,0 +1,14 @@
+[package]
+name = "filler-examples"
+authors = ["Antonio Yang <yanganto@gmail.com>"]
+version = "0.14.1"
+edition = "2021"
+license = "MIT"
+
+[dependencies]
+struct-patch = { path = "../../lib" }
+
+[features]
+default = ["status", "op"]
+status = ["struct-patch/status"]
+op = ["struct-patch/op"]
diff --git a/lib/examples/filler-op.rs b/examples/filler-examples/examples/filler-op.rs
similarity index 100%
rename from lib/examples/filler-op.rs
rename to examples/filler-examples/examples/filler-op.rs
diff --git a/lib/examples/filler.rs b/examples/filler-examples/examples/filler.rs
similarity index 100%
rename from lib/examples/filler.rs
rename to examples/filler-examples/examples/filler.rs
diff --git a/no-std-examples/.cargo/config.toml b/examples/no-std-examples/.cargo/config.toml
similarity index 100%
rename from no-std-examples/.cargo/config.toml
rename to examples/no-std-examples/.cargo/config.toml
diff --git a/no-std-examples/Cargo.toml b/examples/no-std-examples/Cargo.toml
similarity index 92%
rename from no-std-examples/Cargo.toml
rename to examples/no-std-examples/Cargo.toml
index ddaaf9f..3a5f0d7 100644
--- a/no-std-examples/Cargo.toml
+++ b/examples/no-std-examples/Cargo.toml
@@ -6,7 +6,7 @@ edition = "2021"
 license = "MIT"
 
 [dependencies]
-struct-patch = { path = "../lib" }
+struct-patch = { path = "../../lib" }
 linked_list_allocator = "0.10"
 cortex-m-rt = "0.7"
 cortex-m-semihosting = "0.5"
diff --git a/no-std-examples/build.rs b/examples/no-std-examples/build.rs
similarity index 100%
rename from no-std-examples/build.rs
rename to examples/no-std-examples/build.rs
diff --git a/no-std-examples/memory.x b/examples/no-std-examples/memory.x
similarity index 100%
rename from no-std-examples/memory.x
rename to examples/no-std-examples/memory.x
diff --git a/no-std-examples/src/box.rs b/examples/no-std-examples/src/box.rs
similarity index 100%
rename from no-std-examples/src/box.rs
rename to examples/no-std-examples/src/box.rs
diff --git a/no-std-examples/src/option.rs b/examples/no-std-examples/src/option.rs
similarity index 100%
rename from no-std-examples/src/option.rs
rename to examples/no-std-examples/src/option.rs
diff --git a/examples/patch-examples/Cargo.toml b/examples/patch-examples/Cargo.toml
new file mode 100644
index 0000000..7b47aa8
--- /dev/null
+++ b/examples/patch-examples/Cargo.toml
@@ -0,0 +1,32 @@
+[package]
+name = "patch-examples"
+authors = ["Antonio Yang <yanganto@gmail.com>"]
+version = "0.14.1"
+edition = "2021"
+license = "MIT"
+
+[dependencies]
+struct-patch = { path = "../../lib" }
+serde_json = "1.0"
+serde = { version = "1", features = ["derive"] }
+serde_with = "3.9.0"
+toml = "1.1.2"
+humantime-serde = "1.1.1"
+clap = { version = "4.4.7", features = ["derive"] }
+
+[features]
+default = ["status", "op"]
+status = ["struct-patch/status"]
+op = ["struct-patch/op"]
+merge = ["struct-patch/merge"]
+alloc = ["struct-patch/alloc"]
+std = ["box", "option"]
+box = ["alloc", "struct-patch/box"]
+option = ["struct-patch/option"]
+nesting = ["struct-patch/nesting"]
+none_as_default = ["option", "struct-patch/none_as_default"]
+keep_none = ["option", "struct-patch/keep_none"]
+
+[[example]]
+name = "box"
+required-features = ["box"]
diff --git a/lib/examples/apply-by.rs b/examples/patch-examples/examples/apply-by.rs
similarity index 100%
rename from lib/examples/apply-by.rs
rename to examples/patch-examples/examples/apply-by.rs
diff --git a/lib/examples/box.rs b/examples/patch-examples/examples/box.rs
similarity index 100%
rename from lib/examples/box.rs
rename to examples/patch-examples/examples/box.rs
diff --git a/lib/examples/clap.rs b/examples/patch-examples/examples/clap.rs
similarity index 100%
rename from lib/examples/clap.rs
rename to examples/patch-examples/examples/clap.rs
diff --git a/lib/examples/diff.rs b/examples/patch-examples/examples/diff.rs
similarity index 100%
rename from lib/examples/diff.rs
rename to examples/patch-examples/examples/diff.rs
diff --git a/lib/examples/instance.rs b/examples/patch-examples/examples/instance.rs
similarity index 100%
rename from lib/examples/instance.rs
rename to examples/patch-examples/examples/instance.rs
diff --git a/lib/examples/json.rs b/examples/patch-examples/examples/json.rs
similarity index 100%
rename from lib/examples/json.rs
rename to examples/patch-examples/examples/json.rs
diff --git a/lib/examples/log.rs b/examples/patch-examples/examples/log.rs
similarity index 100%
rename from lib/examples/log.rs
rename to examples/patch-examples/examples/log.rs
diff --git a/lib/examples/nesting.rs b/examples/patch-examples/examples/nesting.rs
similarity index 100%
rename from lib/examples/nesting.rs
rename to examples/patch-examples/examples/nesting.rs
diff --git a/lib/examples/op.rs b/examples/patch-examples/examples/op.rs
similarity index 100%
rename from lib/examples/op.rs
rename to examples/patch-examples/examples/op.rs
diff --git a/lib/examples/option.rs b/examples/patch-examples/examples/option.rs
similarity index 100%
rename from lib/examples/option.rs
rename to examples/patch-examples/examples/option.rs
diff --git a/lib/examples/patch-attr.rs b/examples/patch-examples/examples/patch-attr.rs
similarity index 100%
rename from lib/examples/patch-attr.rs
rename to examples/patch-examples/examples/patch-attr.rs
diff --git a/lib/examples/rename-patch-struct.rs b/examples/patch-examples/examples/rename-patch-struct.rs
similarity index 100%
rename from lib/examples/rename-patch-struct.rs
rename to examples/patch-examples/examples/rename-patch-struct.rs
diff --git a/lib/examples/status.rs b/examples/patch-examples/examples/status.rs
similarity index 100%
rename from lib/examples/status.rs
rename to examples/patch-examples/examples/status.rs
diff --git a/lib/examples/time.rs b/examples/patch-examples/examples/time.rs
similarity index 100%
rename from lib/examples/time.rs
rename to examples/patch-examples/examples/time.rs
diff --git a/flake.nix b/flake.nix
index 438c6d5..fb330d7 100644
--- a/flake.nix
+++ b/flake.nix
@@ -13,64 +13,35 @@
         pkgs = import nixpkgs {
           inherit system overlays;
         };
-        publishScript = pkgs.writeShellScriptBin "crate-publish" ''
-          cargo login $1
-          cargo publish -p struct-patch-derive || echo "publish struct-patch-derive fail"
-          sleep 10
-          cargo publish -p struct-patch
-        '';
-        checkCatalystScript = pkgs.writeShellScriptBin "check-catalyst" ''
-          set -ex
-          cd $(git rev-parse --show-toplevel 2>/dev/null)
-          cd complex-example
-          cargo test --quiet -p substrate
-          cargo test --quiet -p catalyst
-          cargo test --quiet -p catalyst-src
 
-          echo "Run catatyst test with unsafe features"
-          cargo test --quiet -p catalyst --features unsafe
-          cargo test --quiet -p catalyst-src --features unsafe
+        publishScript = pkgs.writeShellScriptBin "crate-publish"
+          (builtins.readFile ./nix/scripts/crate-publish.sh);
+        checkNoStdScript = pkgs.writeShellScriptBin "check-no-std"
+          (builtins.readFile ./nix/scripts/check-no-std.sh);
+        checkComplexScript = pkgs.writeShellScriptBin "check-complex"
+          (builtins.readFile ./nix/scripts/check-complex.sh);
+        checkFillerScript = pkgs.writeShellScriptBin "check-filler"
+          (builtins.readFile ./nix/scripts/check-filler.sh);
+        checkPatchScript = pkgs.writeShellScriptBin "check-patch"
+          (builtins.readFile ./nix/scripts/check-patch.sh);
+        testScript = pkgs.writeShellScriptBin "test"
+          (builtins.readFile ./nix/scripts/test.sh);
+        PROMPT = ''
+          _git_ps1() {
+              git rev-parse --is-inside-work-tree &>/dev/null || return
+              local branch dirty
+              branch=$(git symbolic-ref --short HEAD 2>/dev/null)
+              [[ -n $(git status --porcelain) ]] && dirty='*'
+              echo "<$branch$dirty>"
+          }
+          PS1='\[\e[33m\][$DEVSHELL] \w $(_git_ps1) \$\[\e[0m\] '
         '';
       in
-      with pkgs;
       {
-        devShells = let
-          noStdRust = rust-bin.stable.latest.default.override {
-            targets = [
-              "thumbv7m-none-eabi"
-            ];
-            extensions = [ "rust-src" "llvm-tools-preview" ];
-          };
-        in
-        {
-          default = mkShell {
-            buildInputs = [
-              rust-bin.stable.latest.minimal
-              openssl
-              pkg-config
-
-              checkCatalystScript 
-            ];
-          };
-
-          ci = mkShell {
-            buildInputs = [
-              rust-bin.stable.latest.default
-              openssl
-              pkg-config
-
-              publishScript
-
-              checkCatalystScript
-            ];
-          };
-
-          no-std = mkShell {
-            buildInputs = [
-              noStdRust 
-              qemu
-            ];
-          };
+        devShells = {
+          default = import ./nix/shells/default.nix { inherit pkgs PROMPT; checkScripts = [ checkComplexScript checkFillerScript checkPatchScript testScript ]; };
+          ci = import ./nix/shells/ci.nix { inherit pkgs publishScript PROMPT; checkScripts = [ checkComplexScript checkFillerScript checkPatchScript testScript ]; };
+          no-std = import ./nix/shells/no-std.nix { inherit pkgs PROMPT; checkScripts = [ checkNoStdScript ]; };
         };
       }
     );
diff --git a/lib/Cargo.toml b/lib/Cargo.toml
index b9e9822..2f3b61b 100644
--- a/lib/Cargo.toml
+++ b/lib/Cargo.toml
@@ -15,12 +15,8 @@ rust-version.workspace = true
 struct-patch-derive = { version = "=0.14.1", path = "../derive" }
 
 [dev-dependencies]
-serde_json = "1.0"
 serde = { version = "1", features = ["derive"] }
-serde_with = "3.9.0"
-toml = "1.1.2"
-humantime-serde = "1.1.1"
-clap = { version = "4.4.7", features = ["derive"] }
+serde_json = "1.0"
 
 [features]
 default = ["status", "op"]
@@ -54,7 +50,3 @@ unsafe = [
     "struct-patch-derive/unsafe"
 ]
 
-
-[[example]]
-name = "box"
-required-features = ["box"]
diff --git a/nix/scripts/check-complex.sh b/nix/scripts/check-complex.sh
new file mode 100644
index 0000000..6ff60bf
--- /dev/null
+++ b/nix/scripts/check-complex.sh
@@ -0,0 +1,10 @@
+set -ex
+cd $(git rev-parse --show-toplevel 2>/dev/null)
+cd examples/complex-examples
+cargo test --quiet -p substrate
+cargo test --quiet -p catalyst
+cargo test --quiet -p catalyst-src
+
+echo "Run catalyst test with unsafe features"
+cargo test --quiet -p catalyst --features unsafe
+cargo test --quiet -p catalyst-src --features unsafe
diff --git a/nix/scripts/check-filler.sh b/nix/scripts/check-filler.sh
new file mode 100644
index 0000000..9b56287
--- /dev/null
+++ b/nix/scripts/check-filler.sh
@@ -0,0 +1,25 @@
+set -ex
+cd $(git rev-parse --show-toplevel 2>/dev/null)
+cd examples/filler-examples
+
+run_no_default() {
+    cargo run --quiet --no-default-features --example filler
+}
+
+run_default() {
+    cargo run --quiet --example filler
+    cargo run --quiet --example filler-op
+}
+
+case "${1:-}" in
+    no-default)
+        run_no_default
+        ;;
+    default)
+        run_default
+        ;;
+    *)
+        run_no_default
+        run_default
+        ;;
+esac
diff --git a/nix/scripts/check-no-std.sh b/nix/scripts/check-no-std.sh
new file mode 100644
index 0000000..68210f8
--- /dev/null
+++ b/nix/scripts/check-no-std.sh
@@ -0,0 +1,5 @@
+set -ex
+cd $(git rev-parse --show-toplevel 2>/dev/null)
+cd examples/no-std-examples
+cargo run --quiet --features=box --bin no-std-box
+cargo run --quiet --features=option --bin no-std-option
diff --git a/nix/scripts/check-patch.sh b/nix/scripts/check-patch.sh
new file mode 100644
index 0000000..c1bf126
--- /dev/null
+++ b/nix/scripts/check-patch.sh
@@ -0,0 +1,78 @@
+set -ex
+cd $(git rev-parse --show-toplevel 2>/dev/null)
+cd examples/patch-examples
+
+run_no_default() {
+    cargo run --quiet --no-default-features --example instance
+    cargo run --quiet --no-default-features --example diff
+    cargo run --quiet --no-default-features --example json
+    cargo run --quiet --no-default-features --example rename-patch-struct
+    cargo run --quiet --no-default-features --example patch-attr
+    cargo run --quiet --no-default-features --example time
+    cargo run --quiet --no-default-features --example clap
+    cargo run --quiet --no-default-features --features=nesting --example nesting
+    cargo run --quiet --no-default-features --features=option --example option
+    cargo run --quiet --no-default-features --example log
+    cargo run --quiet --no-default-features --example apply-by
+    cargo run --quiet --no-default-features --features=box --example box
+}
+
+run_std() {
+    cargo run --quiet --features=std --example instance
+    cargo run --quiet --features=std --example diff
+    cargo run --quiet --features=std --example json
+    cargo run --quiet --features=std --example rename-patch-struct
+    cargo run --quiet --features=std --example patch-attr
+    cargo run --quiet --features=std --example option
+    cargo run --quiet --features=std --example box
+    cargo run --quiet --features=std,nesting --example nesting
+}
+
+run_merge() {
+    cargo run --quiet --features=option,merge --example option
+    cargo run --quiet --features=merge --example op
+    cargo run --quiet --features=merge,nesting --example nesting
+}
+
+run_option() {
+    cargo run --quiet --features=none_as_default --example option
+    cargo run --quiet --features=none_as_default,nesting --example nesting
+    cargo run --quiet --features=keep_none --example option
+    cargo run --quiet --features=keep_none,nesting --example nesting
+}
+
+run_default() {
+    cargo run --quiet --example status
+    cargo run --quiet --example op
+    cargo run --quiet --example clap
+    cargo run --quiet --features=nesting --example nesting
+    cargo run --quiet --features=nesting --example clap
+    cargo run --quiet --example log
+    cargo run --quiet --example apply-by
+    cargo run --quiet --features=box --example box
+}
+
+case "${1:-}" in
+    no-default)
+        run_no_default
+        ;;
+    std)
+        run_std
+        ;;
+    merge)
+        run_merge
+        ;;
+    option)
+        run_option
+        ;;
+    default)
+        run_default
+        ;;
+    *)
+        run_no_default
+        run_std
+        run_merge
+        run_option
+        run_default
+        ;;
+esac
diff --git a/nix/scripts/crate-publish.sh b/nix/scripts/crate-publish.sh
new file mode 100644
index 0000000..b579d4b
--- /dev/null
+++ b/nix/scripts/crate-publish.sh
@@ -0,0 +1,4 @@
+cargo login $1
+cargo publish -p struct-patch-derive || echo "publish struct-patch-derive fail"
+sleep 10
+cargo publish -p struct-patch
diff --git a/nix/scripts/test.sh b/nix/scripts/test.sh
new file mode 100644
index 0000000..5ec58ff
--- /dev/null
+++ b/nix/scripts/test.sh
@@ -0,0 +1,40 @@
+set -ex
+cd $(git rev-parse --show-toplevel 2>/dev/null)
+
+run_no_default() {
+    cargo test --quiet --no-default-features
+}
+
+run_std() {
+    cargo test --quiet --features=std
+}
+
+run_merge() {
+    cargo test --quiet --features=merge --no-default-features
+    cargo test --quiet --features=merge
+}
+
+run_default() {
+    cargo test --quiet
+}
+
+case "${1:-}" in
+    no-default)
+        run_no_default
+        ;;
+    std)
+        run_std
+        ;;
+    merge)
+        run_merge
+        ;;
+    default)
+        run_default
+        ;;
+    *)
+        run_no_default
+        run_std
+        run_merge
+        run_default
+        ;;
+esac
diff --git a/nix/shells/ci.nix b/nix/shells/ci.nix
new file mode 100644
index 0000000..d919d7b
--- /dev/null
+++ b/nix/shells/ci.nix
@@ -0,0 +1,14 @@
+{ pkgs, publishScript, checkScripts, PROMPT ? "" }:
+pkgs.mkShell {
+  name = "ci";
+  shellHook = ''
+    export DEVSHELL=ci
+    ${PROMPT}
+  '';
+  buildInputs = [
+    pkgs.rust-bin.stable.latest.default
+    pkgs.openssl
+    pkgs.pkg-config
+    publishScript
+  ] ++ checkScripts;
+}
diff --git a/nix/shells/default.nix b/nix/shells/default.nix
new file mode 100644
index 0000000..9a5a91f
--- /dev/null
+++ b/nix/shells/default.nix
@@ -0,0 +1,15 @@
+{ pkgs, checkScripts, PROMPT ? "" }:
+pkgs.mkShell {
+  name = "default";
+  shellHook = ''
+    export DEVSHELL=default
+    ${PROMPT}
+    echo "Scripts:"
+    ${builtins.concatStringsSep "\n" (map (s: "echo \"  ${s.name}\"") checkScripts)}
+  '';
+  buildInputs = [
+    pkgs.rust-bin.stable.latest.minimal
+    pkgs.openssl
+    pkgs.pkg-config
+  ] ++ checkScripts;
+}
diff --git a/nix/shells/no-std.nix b/nix/shells/no-std.nix
new file mode 100644
index 0000000..3a6a235
--- /dev/null
+++ b/nix/shells/no-std.nix
@@ -0,0 +1,20 @@
+{ pkgs, checkScripts, PROMPT ? "" }:
+let
+  noStdRust = pkgs.rust-bin.stable.latest.default.override {
+    targets = [ "thumbv7m-none-eabi" ];
+    extensions = [ "rust-src" "llvm-tools-preview" ];
+  };
+in
+pkgs.mkShell {
+  name = "no-std";
+  shellHook = ''
+    export DEVSHELL=no-std
+    ${PROMPT}
+    echo "Scripts:"
+    ${builtins.concatStringsSep "\n" (map (s: "echo \"  ${s.name}\"") checkScripts)}
+  '';
+  buildInputs = [
+    noStdRust
+    pkgs.qemu
+  ] ++ checkScripts;
+}