diff --git a/.gitattributes b/.gitattributes
new file mode 100644
index 00000000..d9e4eec2
--- /dev/null
+++ b/.gitattributes
@@ -0,0 +1,5 @@
+# Set the default behavior, in case people don't have core.autocrlf set.
+* text=auto
+
+# Declare files that will always have LF line endings on checkout.
+*.sh test eol=lf
diff --git a/examples/PutObject.cc b/examples/PutObject.cc
index 14071d38..0857b2ad 100644
--- a/examples/PutObject.cc
+++ b/examples/PutObject.cc
@@ -13,7 +13,16 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
+#include <fstream>
+#include <iosfwd>
+#include <iostream>
+#include <ostream>
+
+#include "args.h"
 #include "client.h"
+#include "providers.h"
+#include "request.h"
+#include "response.h"
 
 int main() {
   // Create S3 base URL.
diff --git a/examples/PutObjectProgress.cc b/examples/PutObjectProgress.cc
index aae1cc8d..48c99f1d 100644
--- a/examples/PutObjectProgress.cc
+++ b/examples/PutObjectProgress.cc
@@ -13,7 +13,17 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
+#include <fstream>
+#include <iosfwd>
+#include <iostream>
+#include <ostream>
+
+#include "args.h"
 #include "client.h"
+#include "http.h"
+#include "providers.h"
+#include "request.h"
+#include "response.h"
 
 int main() {
   // Create S3 base URL.
diff --git a/include/args.h b/include/args.h
index 227595c4..6421ca97 100644
--- a/include/args.h
+++ b/include/args.h
@@ -16,10 +16,17 @@
 #ifndef _MINIO_S3_ARGS_H
 #define _MINIO_S3_ARGS_H
 
+#include <functional>
+#include <list>
+#include <map>
+#include <string>
+#include <type_traits>
+
+#include "error.h"
 #include "http.h"
-#include "signer.h"
 #include "sse.h"
 #include "types.h"
+#include "utils.h"
 
 namespace minio {
 namespace s3 {
diff --git a/include/baseclient.h b/include/baseclient.h
index 3ceb1a50..ac9b4b03 100644
--- a/include/baseclient.h
+++ b/include/baseclient.h
@@ -16,11 +16,18 @@
 #ifndef _MINIO_S3_BASE_CLIENT_H
 #define _MINIO_S3_BASE_CLIENT_H
 
+#include <map>
+#include <string>
+#include <type_traits>
+
 #include "args.h"
 #include "config.h"
+#include "error.h"
+#include "http.h"
+#include "providers.h"
 #include "request.h"
 #include "response.h"
-#include "select.h"
+#include "utils.h"
 
 namespace minio {
 namespace s3 {
diff --git a/include/client.h b/include/client.h
index b13be18b..b9169c87 100644
--- a/include/client.h
+++ b/include/client.h
@@ -16,11 +16,13 @@
 #ifndef _MINIO_S3_CLIENT_H
 #define _MINIO_S3_CLIENT_H
 
-#include <fstream>
+#include <list>
+#include <string>
 
 #include "args.h"
 #include "baseclient.h"
-#include "config.h"
+#include "error.h"
+#include "providers.h"
 #include "request.h"
 #include "response.h"
 
diff --git a/include/credentials.h b/include/credentials.h
index 49594b82..039f860a 100644
--- a/include/credentials.h
+++ b/include/credentials.h
@@ -16,6 +16,10 @@
 #ifndef _MINIO_CREDS_CREDENTIALS_H
 #define _MINIO_CREDS_CREDENTIALS_H
 
+#include <string>
+#include <type_traits>
+
+#include "error.h"
 #include "utils.h"
 
 namespace minio {
@@ -34,6 +38,30 @@ struct Credentials {
   utils::UtcTime expiration = {};
 
   Credentials() = default;
+  explicit Credentials(error::Error err) : err(std::move(err)) {}
+
+  explicit Credentials(error::Error err, std::string access_key,
+                       std::string secret_key)
+      : err(std::move(err)),
+        access_key(std::move(access_key)),
+        secret_key(std::move(secret_key)) {}
+
+  explicit Credentials(error::Error err, std::string access_key,
+                       std::string secret_key, std::string session_token)
+      : err(std::move(err)),
+        access_key(std::move(access_key)),
+        secret_key(std::move(secret_key)),
+        session_token(std::move(session_token)) {}
+
+  explicit Credentials(error::Error err, std::string access_key,
+                       std::string secret_key, std::string session_token,
+                       utils::UtcTime expiration)
+      : err(std::move(err)),
+        access_key(std::move(access_key)),
+        secret_key(std::move(secret_key)),
+        session_token(std::move(session_token)),
+        expiration(std::move(expiration)) {}
+
   ~Credentials() = default;
 
   bool IsExpired() const { return expired(expiration); }
diff --git a/include/error.h b/include/error.h
index d8035d13..d8666df9 100644
--- a/include/error.h
+++ b/include/error.h
@@ -18,6 +18,7 @@
 
 #include <ostream>
 #include <string>
+#include <type_traits>
 
 namespace minio {
 namespace error {
@@ -32,9 +33,9 @@ class Error {
   Error(const Error&) = default;
   Error& operator=(const Error&) = default;
 
-  Error(Error&& v) : msg_(std::move(v.msg_)) {}
+  Error(Error&& v) noexcept : msg_(std::move(v.msg_)) {}
 
-  Error& operator=(Error&& v) {
+  Error& operator=(Error&& v) noexcept {
     if (this != &v) {
       msg_ = std::move(v.msg_);
     }
diff --git a/include/http.h b/include/http.h
index 30e45bee..441f6d48 100644
--- a/include/http.h
+++ b/include/http.h
@@ -16,16 +16,15 @@
 #ifndef _MINIO_HTTP_H
 #define _MINIO_HTTP_H
 
-#ifdef _WIN32
-#include <ws2tcpip.h>
-#else
-#include <arpa/inet.h>
-#endif
-
 #include <curlpp/Easy.hpp>
 #include <curlpp/Multi.hpp>
-#include <curlpp/Options.hpp>
+#include <exception>
+#include <functional>
+#include <iostream>
+#include <string>
+#include <type_traits>
 
+#include "error.h"
 #include "utils.h"
 
 namespace minio {
@@ -65,6 +64,13 @@ struct Url {
   std::string query_string;
 
   Url() = default;
+  explicit Url(bool https, std::string host, unsigned int port,
+               std::string path, std::string query_string)
+      : https(https),
+        host(std::move(host)),
+        port(port),
+        path(std::move(path)),
+        query_string(std::move(query_string)) {}
   ~Url() = default;
 
   explicit operator bool() const { return !host.empty(); }
@@ -91,6 +97,16 @@ struct DataFunctionArgs {
   void* userdata = nullptr;
 
   DataFunctionArgs() = default;
+  explicit DataFunctionArgs(curlpp::Easy* handle, Response* response,
+                            void* userdata)
+      : handle(handle), response(response), userdata(userdata) {}
+  explicit DataFunctionArgs(curlpp::Easy* handle, Response* response,
+                            std::string datachunk, void* userdata)
+      : handle(handle),
+        response(response),
+        datachunk(std::move(datachunk)),
+        userdata(userdata) {}
+
   ~DataFunctionArgs() = default;
 };  // struct DataFunctionArgs
 
diff --git a/include/providers.h b/include/providers.h
index 2c36a473..c896548e 100644
--- a/include/providers.h
+++ b/include/providers.h
@@ -16,11 +16,13 @@
 #ifndef _MINIO_CREDS_PROVIDERS_H
 #define _MINIO_CREDS_PROVIDERS_H
 
-#include <sys/types.h>
-
+#include <functional>
+#include <list>
 #include <string>
+#include <type_traits>
 
 #include "credentials.h"
+#include "error.h"
 #include "http.h"
 
 #define DEFAULT_DURATION_SECONDS (60 * 60 * 24)  // 1 day.
@@ -34,6 +36,8 @@ struct Jwt {
   unsigned int expiry = 0;
 
   Jwt() = default;
+  explicit Jwt(std::string token, unsigned int expiry)
+      : token(std::move(token)), expiry(expiry) {}
   ~Jwt() = default;
 
   explicit operator bool() const { return !token.empty(); }
diff --git a/include/request.h b/include/request.h
index 30cdb51c..d9f78034 100644
--- a/include/request.h
+++ b/include/request.h
@@ -16,9 +16,13 @@
 #ifndef _MINIO_REQUEST_H
 #define _MINIO_REQUEST_H
 
-#include "credentials.h"
+#include <regex>
+#include <string>
+
+#include "error.h"
+#include "http.h"
 #include "providers.h"
-#include "signer.h"
+#include "utils.h"
 
 namespace minio {
 namespace s3 {
diff --git a/include/response.h b/include/response.h
index e14b0827..a58c2b36 100644
--- a/include/response.h
+++ b/include/response.h
@@ -16,9 +16,14 @@
 #ifndef _MINIO_S3_RESPONSE_H
 #define _MINIO_S3_RESPONSE_H
 
-#include <pugixml.hpp>
+#include <list>
+#include <map>
+#include <string>
+#include <type_traits>
 
+#include "error.h"
 #include "types.h"
+#include "utils.h"
 
 namespace minio {
 namespace s3 {
diff --git a/include/select.h b/include/select.h
index e1da0a5b..1040f0a6 100644
--- a/include/select.h
+++ b/include/select.h
@@ -16,8 +16,11 @@
 #ifndef _MINIO_S3_SELECT_H
 #define _MINIO_S3_SELECT_H
 
-#include <pugixml.hpp>
+#include <map>
+#include <string>
+#include <type_traits>
 
+#include "error.h"
 #include "http.h"
 #include "types.h"
 
diff --git a/include/signer.h b/include/signer.h
index 9aae4ec9..836c4d03 100644
--- a/include/signer.h
+++ b/include/signer.h
@@ -16,9 +16,10 @@
 #ifndef _MINIO_SIGNER_H
 #define _MINIO_SIGNER_H
 
-#include <openssl/hmac.h>
+#include <string>
 
 #include "http.h"
+#include "utils.h"
 
 namespace minio {
 namespace signer {
diff --git a/include/sse.h b/include/sse.h
index 3edeb7b9..c28111e4 100644
--- a/include/sse.h
+++ b/include/sse.h
@@ -16,6 +16,8 @@
 #ifndef _MINIO_S3_SSE_H
 #define _MINIO_S3_SSE_H
 
+#include <string>
+
 #include "utils.h"
 
 namespace minio {
diff --git a/include/types.h b/include/types.h
index 9a220b06..e5487e7f 100644
--- a/include/types.h
+++ b/include/types.h
@@ -16,10 +16,17 @@
 #ifndef _MINIO_S3_TYPES_H
 #define _MINIO_S3_TYPES_H
 
+#include <exception>
+#include <functional>
 #include <iostream>
-#include <nlohmann/json.hpp>
+#include <list>
+#include <map>
+#include <nlohmann/json_fwd.hpp>
 #include <ostream>
+#include <string>
+#include <type_traits>
 
+#include "error.h"
 #include "utils.h"
 
 namespace minio {
@@ -310,6 +317,8 @@ struct Bucket {
   utils::UtcTime creation_date;
 
   Bucket() = default;
+  explicit Bucket(std::string name, utils::UtcTime creation_date)
+      : name(std::move(name)), creation_date(std::move(creation_date)) {}
   ~Bucket() = default;
 };  // struct Bucket
 
@@ -320,6 +329,8 @@ struct Part {
   size_t size = 0;
 
   Part() = default;
+  explicit Part(unsigned int number, std::string etag)
+      : number(number), etag(std::move(etag)) {}
   ~Part() = default;
 };  // struct Part
 
diff --git a/include/utils.h b/include/utils.h
index d3e339a9..82095679 100644
--- a/include/utils.h
+++ b/include/utils.h
@@ -20,34 +20,23 @@
 #include <pwd.h>
 #endif
 
-#include <openssl/buffer.h>
-#include <openssl/evp.h>
-#include <sys/types.h>
-#include <zlib.h>
-
-#include <array>
-#include <chrono>
-#include <cmath>
-#include <cstring>
 #include <ctime>
-#include <curlpp/cURLpp.hpp>
-#include <iomanip>
-#include <iostream>
+#include <ios>
 #include <list>
 #include <map>
-#include <ostream>
-#include <regex>
 #include <set>
-#include <sstream>
+#include <streambuf>
+#include <string>
+#include <vector>
 
 #include "error.h"
 
 namespace minio {
 namespace utils {
-inline constexpr unsigned int kMaxMultipartCount = 10000;  // 10000 parts
-inline constexpr unsigned long long kMaxObjectSize = 5497558138880ULL;  // 5TiB
-inline constexpr unsigned long long kMaxPartSize = 5368709120UL;        // 5GiB
-inline constexpr unsigned int kMinPartSize = 5 * 1024 * 1024;           // 5MiB
+inline constexpr unsigned int kMaxMultipartCount = 10000;      // 10000 parts
+inline constexpr uint64_t kMaxObjectSize = 5'497'558'138'880;  // 5TiB
+inline constexpr uint64_t kMaxPartSize = 5'368'709'120;        // 5GiB
+inline constexpr unsigned int kMinPartSize = 5 * 1024 * 1024;  // 5MiB
 
 // GetEnv copies the environment variable name into var
 bool GetEnv(std::string& var, const char* name);
@@ -72,7 +61,7 @@ inline const char* BoolToString(bool b) { return b ? "true" : "false"; }
 // Trim trims leading and trailing character of a string.
 std::string Trim(std::string_view str, char ch = ' ');
 
-// CheckNonemptystring checks whether string is not empty after trimming
+// CheckNonEmptyString checks whether string is not empty after trimming
 // whitespaces.
 bool CheckNonEmptyString(std::string_view str);
 
diff --git a/src/args.cc b/src/args.cc
index dc7c9582..ed797f9d 100644
--- a/src/args.cc
+++ b/src/args.cc
@@ -15,8 +15,21 @@
 
 #include "args.h"
 
+#include <curlpp/cURLpp.hpp>
+#include <exception>
 #include <filesystem>
+#include <iostream>
+#include <map>
 #include <nlohmann/json.hpp>
+#include <ostream>
+#include <string>
+#include <type_traits>
+
+#include "error.h"
+#include "http.h"
+#include "signer.h"
+#include "types.h"
+#include "utils.h"
 
 minio::error::Error minio::s3::BucketArgs::Validate() const {
   return utils::CheckBucketName(bucket);
@@ -346,7 +359,7 @@ minio::error::Error minio::s3::ComposeSource::BuildHeaders(
 size_t minio::s3::ComposeSource::ObjectSize() const {
   if (object_size_ == -1) {
     std::cerr << "ABORT: ComposeSource::BuildHeaders() must be called prior to "
-                 "this method invocation. This shoud not happen."
+                 "this method invocation. This should not happen."
               << std::endl;
     std::terminate();
   }
@@ -357,7 +370,7 @@ size_t minio::s3::ComposeSource::ObjectSize() const {
 minio::utils::Multimap minio::s3::ComposeSource::Headers() const {
   if (!headers_) {
     std::cerr << "ABORT: ComposeSource::BuildHeaders() must be called prior to "
-                 "this method invocation. This shoud not happen."
+                 "this method invocation. This should not happen."
               << std::endl;
     std::terminate();
   }
@@ -441,7 +454,7 @@ minio::error::Error minio::s3::ListenBucketNotificationArgs::Validate() const {
     return err;
   }
   if (func == nullptr) {
-    error::Error("notification records function must be set");
+    return error::Error("notification records function must be set");
   }
   return error::SUCCESS;
 }
diff --git a/src/baseclient.cc b/src/baseclient.cc
index 3b51baa5..0925ce32 100644
--- a/src/baseclient.cc
+++ b/src/baseclient.cc
@@ -15,6 +15,32 @@
 
 #include "baseclient.h"
 
+#include <cstring>
+#include <exception>
+#include <functional>
+#include <iostream>
+#include <list>
+#include <map>
+#include <nlohmann/json.hpp>
+#include <ostream>
+#include <pugixml.hpp>
+#include <sstream>
+#include <string>
+#include <type_traits>
+
+#include "args.h"
+#include "config.h"
+#include "credentials.h"
+#include "error.h"
+#include "http.h"
+#include "providers.h"
+#include "request.h"
+#include "response.h"
+#include "select.h"
+#include "signer.h"
+#include "types.h"
+#include "utils.h"
+
 minio::utils::Multimap minio::s3::GetCommonListObjectsQueryParams(
     const std::string& delimiter, const std::string& encoding_type,
     unsigned int max_keys, const std::string& prefix) {
@@ -955,7 +981,7 @@ minio::s3::BaseClient::GetPresignedPostFormData(PostPolicy policy) {
 
   if (provider_ == nullptr) {
     return error::Error(
-        "Anonymous access does not require presigned post form-data");
+        "Anonymous access does not require pre-signed post form-data");
   }
 
   std::string region;
diff --git a/src/client.cc b/src/client.cc
index 373984ee..5c0e4c40 100644
--- a/src/client.cc
+++ b/src/client.cc
@@ -15,6 +15,26 @@
 
 #include "client.h"
 
+#include <curlpp/cURLpp.hpp>
+#include <filesystem>
+#include <fstream>
+#include <list>
+#include <memory>
+#include <string>
+#include <system_error>
+#include <type_traits>
+
+#include "args.h"
+#include "baseclient.h"
+#include "error.h"
+#include "http.h"
+#include "providers.h"
+#include "request.h"
+#include "response.h"
+#include "sse.h"
+#include "types.h"
+#include "utils.h"
+
 minio::s3::ListObjectsResult::ListObjectsResult(error::Error err)
     : failed_(true) {
   this->resp_.contents.push_back(Item(std::move(err)));
@@ -284,7 +304,7 @@ minio::s3::ComposeObjectResponse minio::s3::Client::ComposeObject(
       upc_args.part_number = part_number;
       UploadPartCopyResponse resp = UploadPartCopy(upc_args);
       if (!resp) return resp;
-      parts.push_back(Part{part_number, resp.etag});
+      parts.push_back(Part(part_number, std::move(resp.etag)));
     } else {
       while (size > 0) {
         part_number++;
@@ -306,10 +326,11 @@ minio::s3::ComposeObjectResponse minio::s3::Client::ComposeObject(
         upc_args.headers = headerscopy;
         upc_args.upload_id = upload_id;
         upc_args.part_number = part_number;
-        UploadPartCopyResponse resp = UploadPartCopy(upc_args);
-        if (!resp) return resp;
-        parts.push_back(Part{part_number, resp.etag});
-
+        {
+          UploadPartCopyResponse resp = UploadPartCopy(upc_args);
+          if (!resp) return resp;
+          parts.push_back(Part(part_number, std::move(resp.etag)));
+        }
         offset = start_bytes;
         size -= (end_bytes - start_bytes);
       }
@@ -475,7 +496,7 @@ minio::s3::PutObjectResponse minio::s3::Client::PutObject(
         actual_args.userdata = args.progress_userdata;
         args.progressfunc(actual_args);
       }
-      parts.push_back(Part{part_number, resp.etag});
+      parts.push_back(Part(part_number, std::move(resp.etag)));
     } else {
       return resp;
     }
diff --git a/src/credentials.cc b/src/credentials.cc
index 085ccf6d..9795b93d 100644
--- a/src/credentials.cc
+++ b/src/credentials.cc
@@ -16,6 +16,11 @@
 #include "credentials.h"
 
 #include <pugixml.hpp>
+#include <string>
+#include <type_traits>
+
+#include "error.h"
+#include "utils.h"
 
 bool minio::creds::expired(const utils::UtcTime& expiration) {
   if (!expiration) return false;
@@ -44,6 +49,7 @@ minio::creds::Credentials minio::creds::Credentials::ParseXML(
   text = credentials.node().select_node("Expiration/text()");
   auto expiration = utils::UtcTime::FromISO8601UTC(text.node().value());
 
-  return Credentials{error::SUCCESS, access_key, secret_key, session_token,
-                     expiration};
+  return Credentials(error::SUCCESS, std::move(access_key),
+                     std::move(secret_key), std::move(session_token),
+                     expiration);
 }
diff --git a/src/http.cc b/src/http.cc
index c4647dd7..f229442e 100644
--- a/src/http.cc
+++ b/src/http.cc
@@ -13,9 +13,37 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-#include "http.h"
+#include <curl/curl.h>
 
+#include <curlpp/Easy.hpp>
+#include <curlpp/Exception.hpp>
 #include <curlpp/Infos.hpp>
+#include <curlpp/Multi.hpp>
+#include <curlpp/Options.hpp>
+#include <curlpp/cURLpp.hpp>
+#include <exception>
+#include <functional>
+#include <iosfwd>
+#include <iostream>
+#include <list>
+#include <ostream>
+#include <sstream>
+#include <stdexcept>
+#include <string>
+#include <type_traits>
+
+#ifdef _WIN32
+#include <WinSock2.h>
+#include <ws2def.h>    // NOTE needed for AF_INET6
+#include <ws2ipdef.h>  // NOTE needed for sockaddr_in6
+#include <ws2tcpip.h>
+#else
+#include <arpa/inet.h>
+#endif
+
+#include "error.h"
+#include "http.h"
+#include "utils.h"
 
 std::string minio::http::Url::String() const {
   if (host.empty()) return {};
@@ -105,7 +133,8 @@ minio::http::Url minio::http::Url::Parse(std::string value) {
   if (!https && port == 80) port = 0;
   if (https && port == 443) port = 0;
 
-  return Url{https, host, port, path, query_string};
+  return Url(https, std::move(host), port, std::move(path),
+             std::move(query_string));
 }
 
 minio::error::Error minio::http::Response::ReadStatusCode() {
@@ -248,7 +277,8 @@ size_t minio::http::Response::ResponseCallback(curlpp::Multi* const requests,
 
     // If data function is set and the request is successful, send data.
     if (datafunc != nullptr && status_code >= 200 && status_code <= 299) {
-      DataFunctionArgs args{request, this, response_, userdata};
+      DataFunctionArgs args(request, this, std::string(this->response_),
+                            userdata);
       if (!datafunc(args)) requests->remove(request);
     } else {
       body = response_;
@@ -259,7 +289,7 @@ size_t minio::http::Response::ResponseCallback(curlpp::Multi* const requests,
 
   // If data function is set and the request is successful, send data.
   if (datafunc != nullptr && status_code >= 200 && status_code <= 299) {
-    DataFunctionArgs args{request, this, std::string(buffer, length), userdata};
+    DataFunctionArgs args(request, this, std::string(buffer, length), userdata);
     if (!datafunc(args)) requests->remove(request);
   } else {
     body.append(buffer, length);
@@ -368,9 +398,9 @@ minio::http::Response minio::http::Request::execute() {
   while (!requests.perform(&left)) {
   }
   while (left) {
-    fd_set fdread;
-    fd_set fdwrite;
-    fd_set fdexcep;
+    fd_set fdread{};
+    fd_set fdwrite{};
+    fd_set fdexcep{};
     int maxfd = 0;
 
     FD_ZERO(&fdread);
diff --git a/src/providers.cc b/src/providers.cc
index 73882d5b..2fe2a1ad 100644
--- a/src/providers.cc
+++ b/src/providers.cc
@@ -17,22 +17,32 @@
 #define _WINSOCK_DEPRECATED_NO_WARNINGS
 #endif
 
-#include "providers.h"
-
 #include <INIReader.h>
 
 #include <fstream>
+#include <iosfwd>
+#include <list>
 #include <nlohmann/json.hpp>
+#include <string>
+#include <type_traits>
 
-#include "signer.h"
-#include "utils.h"
-
-#ifndef _WIN32
+#ifdef _WIN32
+#include <WinSock2.h>
+#include <ws2def.h>
+#include <ws2tcpip.h>
+#else
 #include <arpa/inet.h>
 #include <netdb.h>
 #include <sys/socket.h>
 #endif
 
+#include "credentials.h"
+#include "error.h"
+#include "http.h"
+#include "providers.h"
+#include "signer.h"
+#include "utils.h"
+
 minio::error::Error minio::creds::checkLoopbackHost(const std::string& host) {
   struct addrinfo hints = {};
   hints.ai_family = AF_INET;
@@ -82,8 +92,8 @@ minio::creds::Credentials minio::creds::ChainedProvider::Fetch() {
 minio::creds::StaticProvider::StaticProvider(std::string access_key,
                                              std::string secret_key,
                                              std::string session_token) {
-  this->creds_ = Credentials{error::SUCCESS, std::move(access_key),
-                             std::move(secret_key), std::move(session_token)};
+  this->creds_ = Credentials(error::SUCCESS, std::move(access_key),
+                             std::move(secret_key), std::move(session_token));
 }
 
 minio::creds::StaticProvider::~StaticProvider() {}
@@ -105,8 +115,8 @@ minio::creds::EnvAwsProvider::EnvAwsProvider() {
   }
   utils::GetEnv(session_token, "AWS_SESSION_TOKEN");
 
-  this->creds_ =
-      Credentials{error::SUCCESS, access_key, secret_key, session_token};
+  this->creds_ = Credentials(error::SUCCESS, std::move(access_key),
+                             std::move(secret_key), std::move(session_token));
 }
 
 minio::creds::EnvAwsProvider::~EnvAwsProvider() {}
@@ -121,7 +131,8 @@ minio::creds::EnvMinioProvider::EnvMinioProvider() {
 
   utils::GetEnv(access_key, "MINIO_ACCESS_KEY");
   utils::GetEnv(secret_key, "MINIO_SECRET_KEY");
-  this->creds_ = Credentials{error::SUCCESS, access_key, secret_key};
+  this->creds_ =
+      Credentials(error::SUCCESS, std::move(access_key), std::move(secret_key));
 }
 
 minio::creds::EnvMinioProvider::~EnvMinioProvider() {}
@@ -379,7 +390,7 @@ minio::creds::Credentials minio::creds::IamAwsProvider::Fetch() {
           std::ifstream ifs(token_file);
           nlohmann::json json = nlohmann::json::parse(ifs);
           ifs.close();
-          return Jwt{json["access_token"], json["expires_in"]};
+          return Jwt(std::move(json["access_token"]), json["expires_in"]);
         },
         url, 0, "", role_arn_, role_session_name_);
     creds_ = provider.Fetch();
diff --git a/src/request.cc b/src/request.cc
index d07aaaf9..30ead666 100644
--- a/src/request.cc
+++ b/src/request.cc
@@ -15,6 +15,23 @@
 
 #include "request.h"
 
+#include <exception>
+#include <iosfwd>
+#include <iostream>
+#include <ostream>
+#include <regex>
+#include <sstream>
+#include <string>
+#include <type_traits>
+#include <vector>
+
+#include "credentials.h"
+#include "error.h"
+#include "http.h"
+#include "providers.h"
+#include "signer.h"
+#include "utils.h"
+
 #define EMPTY_SHA256 \
   "e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855"
 
@@ -199,7 +216,8 @@ minio::error::Error minio::s3::BaseUrl::BuildUrl(
     return error::Error("empty bucket name for object name " + object_name);
   }
 
-  url = http::Url{https, host, port, "/", query_params.ToQueryString()};
+  url = http::Url(https, std::string(this->host), port, "/",
+                  query_params.ToQueryString());
 
   if (bucket_name.empty()) {
     this->BuildListBucketsUrl(url, region);
diff --git a/src/response.cc b/src/response.cc
index c922d92c..e40a145f 100644
--- a/src/response.cc
+++ b/src/response.cc
@@ -15,6 +15,18 @@
 
 #include "response.h"
 
+#include <cstring>
+#include <curlpp/cURLpp.hpp>
+#include <list>
+#include <map>
+#include <pugixml.hpp>
+#include <string>
+#include <type_traits>
+
+#include "error.h"
+#include "types.h"
+#include "utils.h"
+
 minio::s3::Response::Response() {}
 
 minio::s3::Response::~Response() {}
@@ -90,7 +102,7 @@ minio::s3::ListBucketsResponse minio::s3::ListBucketsResponse::ParseXML(
       creation_date = utils::UtcTime::FromISO8601UTC(value.c_str());
     }
 
-    buckets.push_back(Bucket{name, creation_date});
+    buckets.push_back(Bucket(std::move(name), std::move(creation_date)));
   }
 
   return buckets;
diff --git a/src/select.cc b/src/select.cc
index 40d3f219..691dfa26 100644
--- a/src/select.cc
+++ b/src/select.cc
@@ -15,6 +15,15 @@
 
 #include "select.h"
 
+#include <map>
+#include <pugixml.hpp>
+#include <string>
+
+#include "error.h"
+#include "http.h"
+#include "types.h"
+#include "utils.h"
+
 void minio::s3::SelectHandler::Reset() {
   prelude_.clear();
   prelude_read_ = false;
diff --git a/src/signer.cc b/src/signer.cc
index f33af171..227554da 100644
--- a/src/signer.cc
+++ b/src/signer.cc
@@ -15,6 +15,17 @@
 
 #include "signer.h"
 
+#include <openssl/evp.h>
+#include <openssl/hmac.h>
+
+#include <array>
+#include <cstdio>
+#include <string>
+#include <type_traits>
+
+#include "http.h"
+#include "utils.h"
+
 const char* SIGN_V4_ALGORITHM = "AWS4-HMAC-SHA256";
 
 std::string minio::signer::GetScope(const utils::UtcTime& time,
diff --git a/src/sse.cc b/src/sse.cc
index c47377f7..b3e07285 100644
--- a/src/sse.cc
+++ b/src/sse.cc
@@ -15,6 +15,10 @@
 
 #include "sse.h"
 
+#include <string>
+
+#include "utils.h"
+
 minio::s3::Sse::Sse() {}
 
 minio::s3::Sse::~Sse() {}
diff --git a/src/types.cc b/src/types.cc
index e8048b93..4c26a302 100644
--- a/src/types.cc
+++ b/src/types.cc
@@ -15,6 +15,16 @@
 
 #include "types.h"
 
+#include <exception>
+#include <iosfwd>
+#include <iostream>
+#include <nlohmann/json.hpp>
+#include <ostream>
+#include <sstream>
+#include <string>
+
+#include "error.h"
+
 minio::s3::RetentionMode minio::s3::StringToRetentionMode(
     std::string_view str) noexcept {
   if (str == "GOVERNANCE") return RetentionMode::kGovernance;
diff --git a/src/utils.cc b/src/utils.cc
index 6cadbcfd..b821580d 100644
--- a/src/utils.cc
+++ b/src/utils.cc
@@ -15,12 +15,45 @@
 
 #ifdef _WIN32
 #define _CRT_SECURE_NO_WARNINGS
+#include <corecrt.h>
 #endif
 
+#include <openssl/bio.h>
+#include <openssl/buffer.h>
+#include <openssl/crypto.h>
+#include <openssl/evp.h>
+#include <openssl/types.h>
+#include <zconf.h>
+#include <zlib.h>
+
+#include <algorithm>
+#include <cctype>
+#include <chrono>
+#include <clocale>
+#include <cmath>
+#include <cstdio>
+#include <cstdlib>
+#include <ctime>
+#include <curlpp/cURLpp.hpp>
+#include <exception>
+#include <iomanip>
+#include <ios>
+#include <iosfwd>
+#include <iostream>
+#include <list>
+#include <locale>
+#include <map>
+#include <ostream>
+#include <regex>
+#include <sstream>
+#include <streambuf>
+#include <string>
+#include <type_traits>
+#include <vector>
+
+#include "error.h"
 #include "utils.h"
 
-#include <memory>
-
 const std::string WEEK_DAYS[] = {"Sun", "Mon", "Tue", "Wed",
                                  "Thu", "Fri", "Sat"};
 const std::string MONTHS[] = {"Jan", "Feb", "Mar", "Apr", "May", "Jun",
@@ -370,7 +403,7 @@ minio::utils::UtcTime minio::utils::UtcTime::FromISO8601UTC(const char* value) {
   std::time_t secs = std::mktime(&t);
 
   unsigned long ul = 0;
-  sscanf(rv, ".%lu", &ul);
+  static_cast<void>(sscanf(rv, ".%lu", &ul));
   long usecs = (long)ul;
 
   return UtcTime(secs, usecs);
@@ -563,7 +596,7 @@ minio::error::Error minio::utils::CalcPartInfo(long object_size,
   }
 
   if (object_size >= 0) {
-    if (static_cast<unsigned long long>(object_size) > kMaxObjectSize) {
+    if (static_cast<uint64_t>(object_size) > kMaxObjectSize) {
       return error::Error("object size " + std::to_string(object_size) +
                           " is not supported; maximum allowed 5TiB");
     }
diff --git a/tests/tests.cc b/tests/tests.cc
index dcef9eb5..f836dbe3 100644
--- a/tests/tests.cc
+++ b/tests/tests.cc
@@ -12,11 +12,33 @@
 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 // See the License for the specific language governing permissions and
 // limitations under the License.
+
+#include <array>
 #include <chrono>
+#include <cstdio>
+#include <cstdlib>
+#include <filesystem>
+#include <fstream>
+#include <iosfwd>
+#include <iostream>
+#include <list>
+#include <ostream>
 #include <random>
+#include <sstream>
+#include <stdexcept>
+#include <streambuf>
+#include <string>
 #include <thread>
+#include <utility>
 
+#include "args.h"
 #include "client.h"
+#include "http.h"
+#include "providers.h"
+#include "request.h"
+#include "response.h"
+#include "types.h"
+#include "utils.h"
 
 thread_local static std::mt19937 rg{std::random_device{}()};
 
@@ -534,7 +556,9 @@ class Tests {
         args.bucket = bucket_name_;
         args.object = object_name;
         minio::s3::PutObjectResponse resp = client_.PutObject(args);
-        if (!resp) std::runtime_error("PutObject(): " + resp.Error().String());
+        if (!resp) {
+          throw std::runtime_error("PutObject(): " + resp.Error().String());
+        }
         object_names.push_back(object_name);
       }
       RemoveObjects(object_names);