diff --git a/.github/workflows/ci_core.yml b/.github/workflows/ci_core.yml
index 1402f0c8a4e6..aa4c581b369e 100644
--- a/.github/workflows/ci_core.yml
+++ b/.github/workflows/ci_core.yml
@@ -257,6 +257,6 @@ jobs:
 
       - name: Test
         working-directory: core
-        run: cargo nextest run --no-fail-fast --features layers-all && cargo test --doc
+        run: cargo nextest run --no-fail-fast --features layers-all,tests && cargo test --doc --features tests
         env:
           LD_LIBRARY_PATH: ${{ env.JAVA_HOME }}/lib/server:${{ env.LD_LIBRARY_PATH }}
diff --git a/bin/oli/Cargo.toml b/bin/oli/Cargo.toml
index 3967b802c133..950be3d87588 100644
--- a/bin/oli/Cargo.toml
+++ b/bin/oli/Cargo.toml
@@ -60,7 +60,24 @@ dirs = "5.0.1"
 env_logger = "0.11"
 futures = "0.3"
 log = "0.4"
-opendal = { version = "0.45.1", path = "../../core" }
+opendal = { version = "0.45.1", path = "../../core", features = [
+  # These are default features before v0.46. TODO: change to optional features
+  "services-azblob",
+  "services-azdls",
+  "services-cos",
+  "services-fs",
+  "services-gcs",
+  "services-ghac",
+  "services-http",
+  "services-ipmfs",
+  "services-memory",
+  "services-obs",
+  "services-oss",
+  "services-s3",
+  "services-webdav",
+  "services-webhdfs",
+  "services-azfile",
+] }
 serde = { version = "1", features = ["derive"] }
 tokio = { version = "1.34", features = [
   "fs",
diff --git a/bindings/c/Cargo.toml b/bindings/c/Cargo.toml
index 2b5d051fe7ab..725326e180d7 100644
--- a/bindings/c/Cargo.toml
+++ b/bindings/c/Cargo.toml
@@ -39,5 +39,21 @@ bytes = "1.4.0"
 once_cell = "1.17.1"
 opendal = { version = "0.45.1", path = "../../core", features = [
   "layers-blocking",
+  # These are default features before v0.46. TODO: change to optional features #4313
+  "services-azblob",
+  "services-azdls",
+  "services-cos",
+  "services-fs",
+  "services-gcs",
+  "services-ghac",
+  "services-http",
+  "services-ipmfs",
+  "services-memory",
+  "services-obs",
+  "services-oss",
+  "services-s3",
+  "services-webdav",
+  "services-webhdfs",
+  "services-azfile",
 ] }
 tokio = { version = "1.27", features = ["fs", "macros", "rt-multi-thread"] }
diff --git a/core/Cargo.toml b/core/Cargo.toml
index e95322cffa3f..83155584137e 100644
--- a/core/Cargo.toml
+++ b/core/Cargo.toml
@@ -39,24 +39,7 @@ default-members = ["."]
 members = [".", "fuzz", "edge/*", "benches/vs_*"]
 
 [features]
-default = [
-  "rustls",
-  "services-azblob",
-  "services-azdls",
-  "services-cos",
-  "services-fs",
-  "services-gcs",
-  "services-ghac",
-  "services-http",
-  "services-ipmfs",
-  "services-memory",
-  "services-obs",
-  "services-oss",
-  "services-s3",
-  "services-webdav",
-  "services-webhdfs",
-  "services-azfile",
-]
+default = ["rustls"]
 
 # Build test utils or not.
 #
@@ -64,7 +47,17 @@ default = [
 # And doesn't have any other effects.
 #
 # You should never enable this feature unless you are developing opendal.
-tests = ["dep:rand", "dep:sha2", "dep:dotenvy", "layers-blocking"]
+tests = [
+  "dep:rand",
+  "dep:sha2",
+  "dep:dotenvy",
+  "layers-blocking",
+  "services-azblob",
+  "services-fs",
+  "services-http",
+  "services-memory",
+  "services-s3",
+]
 
 # Enable trust-dns for pure rust dns cache.
 trust-dns = ["reqwest/trust-dns"]
diff --git a/core/edge/file_write_on_full_disk/Cargo.toml b/core/edge/file_write_on_full_disk/Cargo.toml
index 63a57a21a716..5e1c7f7c7a12 100644
--- a/core/edge/file_write_on_full_disk/Cargo.toml
+++ b/core/edge/file_write_on_full_disk/Cargo.toml
@@ -25,6 +25,6 @@ version = "0.0.0"
 
 [dependencies]
 futures = "0.3"
-opendal = { path = "../../" }
+opendal = { path = "../../", features = ["services-memory", "services-fs"] }
 rand = "0.8"
 tokio = { version = "1", features = ["full"] }
diff --git a/core/src/docs/upgrade.md b/core/src/docs/upgrade.md
index 7c56ff1255c0..dfd7198acced 100644
--- a/core/src/docs/upgrade.md
+++ b/core/src/docs/upgrade.md
@@ -1,3 +1,9 @@
+# Upgrade to v0.46
+
+## Services Feature Flag
+
+Starting from v0.46, OpenDAL does not include any services in default features to avoid compiling unneeded services' code. Please enable each service's feature flag to use it.
+
 # Upgrade to v0.45
 
 ## Public API
diff --git a/core/src/lib.rs b/core/src/lib.rs
index 343bbd37d5e2..054dd4f7a0a5 100644
--- a/core/src/lib.rs
+++ b/core/src/lib.rs
@@ -129,8 +129,6 @@
 
 // Make sure all our public APIs have docs.
 #![warn(missing_docs)]
-// Deny unused qualifications.
-#![deny(unused_qualifications)]
 
 // Private module with public types, they will be accessed via `opendal::Xxxx`
 mod types;
diff --git a/core/src/raw/http_util/body.rs b/core/src/raw/http_util/body.rs
index cee80ec1562d..c73aaf374122 100644
--- a/core/src/raw/http_util/body.rs
+++ b/core/src/raw/http_util/body.rs
@@ -76,6 +76,7 @@ impl IncomingAsyncBody {
     }
 
     /// Create an empty IncomingAsyncBody.
+    #[allow(dead_code)]
     pub(crate) fn empty() -> Self {
         Self {
             inner: Box::new(()),
diff --git a/core/src/types/mode.rs b/core/src/types/mode.rs
index c5e45f3fed44..aa8b8d35029c 100644
--- a/core/src/types/mode.rs
+++ b/core/src/types/mode.rs
@@ -41,6 +41,7 @@ impl EntryMode {
     }
 
     /// Create entry mode from given path.
+    #[allow(dead_code)]
     pub(crate) fn from_path(path: &str) -> Self {
         if path.ends_with('/') {
             EntryMode::DIR
diff --git a/core/src/types/operator/builder.rs b/core/src/types/operator/builder.rs
index cca37f72959d..40f265ff885f 100644
--- a/core/src/types/operator/builder.rs
+++ b/core/src/types/operator/builder.rs
@@ -151,6 +151,7 @@ impl Operator {
     ///     Ok(())
     /// }
     /// ```
+    #[allow(unused_variables, unreachable_code)]
     pub fn via_map(scheme: Scheme, map: HashMap<String, String>) -> Result<Operator> {
         let op = match scheme {
             #[cfg(feature = "services-atomicserver")]
diff --git a/integrations/dav-server/Cargo.toml b/integrations/dav-server/Cargo.toml
index 9919526cafa6..d1d82c990342 100644
--- a/integrations/dav-server/Cargo.toml
+++ b/integrations/dav-server/Cargo.toml
@@ -35,7 +35,7 @@ dav-server = { version = "0.5.8" }
 dirs = "5.0.0"
 futures = "0.3"
 futures-util = { version = "0.3.16" }
-opendal = { version = "0.45.1", path = "../../core" }
+opendal = { version = "0.45.1", path = "../../core", features = ["services-fs"] }
 quick-xml = { version = "0.31", features = ["serialize", "overlapped-lists"] }
 serde = { version = "1", features = ["derive"] }
 tokio = { version = "1.27", features = [
diff --git a/integrations/object_store/Cargo.toml b/integrations/object_store/Cargo.toml
index 8b398f47020e..740f274c0fa3 100644
--- a/integrations/object_store/Cargo.toml
+++ b/integrations/object_store/Cargo.toml
@@ -38,3 +38,4 @@ tokio = { version = "1", default-features = false }
 
 [dev-dependencies]
 tokio = { version = "1", features = ["fs", "macros", "rt-multi-thread"] }
+opendal = { version = "0.45.1", path = "../../core", features = ["services-memory"] }
\ No newline at end of file