diff --git a/include/cgimap/backend/apidb/changeset.hpp b/include/cgimap/backend/apidb/changeset.hpp
index 1a5376f4..abdb3071 100644
--- a/include/cgimap/backend/apidb/changeset.hpp
+++ b/include/cgimap/backend/apidb/changeset.hpp
@@ -11,7 +11,6 @@
 #define CHANGESET_HPP
 
 #include "cgimap/types.hpp"
-#include <map>
 #include <set>
 #include <string>
 #include <pqxx/pqxx>
diff --git a/src/api06/changeset_handler.cpp b/src/api06/changeset_handler.cpp
index 0022cab8..33e169a3 100644
--- a/src/api06/changeset_handler.cpp
+++ b/src/api06/changeset_handler.cpp
@@ -14,7 +14,6 @@
 #include <ranges>
 #include <fmt/core.h>
 
-using std::vector;
 
 namespace api06 {
 
diff --git a/src/api06/nodes_handler.cpp b/src/api06/nodes_handler.cpp
index 5d908bfe..b05ec81f 100644
--- a/src/api06/nodes_handler.cpp
+++ b/src/api06/nodes_handler.cpp
@@ -15,17 +15,15 @@
 #include <fmt/core.h>
 #include <fmt/format.h>
 
-using std::vector;
-using std::string;
 
 namespace api06 {
 
-nodes_responder::nodes_responder(mime::type mt, const vector<id_version> &ids,
+nodes_responder::nodes_responder(mime::type mt, const std::vector<id_version> &ids,
                                  data_selection &w)
     : osm_current_responder(mt, w) {
 
-  vector<osm_nwr_id_t> current_ids;
-  vector<osm_edition_t> historic_ids;
+  std::vector<osm_nwr_id_t> current_ids;
+  std::vector<osm_edition_t> historic_ids;
 
   for (const auto &idv : ids) {
     if (idv.version) {
@@ -59,8 +57,8 @@ responder_ptr_t nodes_handler::responder(data_selection &x) const {
  * Validates an FCGI request, returning the valid list of ids or
  * throwing an error if there was no valid list of node ids.
  */
-vector<id_version> nodes_handler::validate_request(const request &req) {
-  vector<id_version> ids = parse_id_list_params(req, "nodes");
+std::vector<id_version> nodes_handler::validate_request(const request &req) {
+  std::vector<id_version> ids = parse_id_list_params(req, "nodes");
 
   if (ids.empty()) {
     throw http::bad_request(
diff --git a/src/api06/relation_full_handler.cpp b/src/api06/relation_full_handler.cpp
index 9473c003..e55fbcc4 100644
--- a/src/api06/relation_full_handler.cpp
+++ b/src/api06/relation_full_handler.cpp
@@ -12,7 +12,6 @@
 #include "cgimap/logger.hpp"
 #include <fmt/core.h>
 
-using std::vector;
 
 namespace api06 {
 
diff --git a/src/api06/relations_handler.cpp b/src/api06/relations_handler.cpp
index 7e7396c9..a81b1e2e 100644
--- a/src/api06/relations_handler.cpp
+++ b/src/api06/relations_handler.cpp
@@ -19,17 +19,15 @@
 #include <string>
 #include <vector>
 
-using std::vector;
-using std::string;
 
 namespace api06 {
 
-relations_responder::relations_responder(mime::type mt, const vector<id_version> &ids,
+relations_responder::relations_responder(mime::type mt, const std::vector<id_version> &ids,
                                          data_selection &s)
     : osm_current_responder(mt, s) {
 
-  vector<osm_nwr_id_t> current_ids;
-  vector<osm_edition_t> historic_ids;
+  std::vector<osm_nwr_id_t> current_ids;
+  std::vector<osm_edition_t> historic_ids;
 
   for (id_version idv : ids) {
     if (idv.version) {
@@ -64,8 +62,8 @@ responder_ptr_t relations_handler::responder(data_selection &x) const {
  * Validates an FCGI request, returning the valid list of ids or
  * throwing an error if there was no valid list of node ids.
  */
-vector<id_version> relations_handler::validate_request(const request &req) {
-  vector<id_version> myids = parse_id_list_params(req, "relations");
+std::vector<id_version> relations_handler::validate_request(const request &req) {
+  std::vector<id_version> myids = parse_id_list_params(req, "relations");
 
   if (myids.empty()) {
     throw http::bad_request("The parameter relations is required, and must be "
diff --git a/src/backend/apidb/apidb.cpp b/src/backend/apidb/apidb.cpp
index a79437d5..99805e65 100644
--- a/src/backend/apidb/apidb.cpp
+++ b/src/backend/apidb/apidb.cpp
@@ -16,7 +16,6 @@
 #include <memory>
 
 namespace po = boost::program_options;
-using std::string;
 
 
 namespace {
@@ -24,32 +23,32 @@ struct apidb_backend : public backend {
   apidb_backend() {
     // clang-format off
     m_options.add_options()
-      ("dbname", po::value<string>()->required(), "database name")
-      ("host", po::value<string>(), "database server host")
-      ("username", po::value<string>(), "database user name")
-      ("password", po::value<string>(), "database password")
-      ("charset", po::value<string>()->default_value("utf8"),
+      ("dbname", po::value<std::string>()->required(), "database name")
+      ("host", po::value<std::string>(), "database server host")
+      ("username", po::value<std::string>(), "database user name")
+      ("password", po::value<std::string>(), "database password")
+      ("charset", po::value<std::string>()->default_value("utf8"),
        "database character set")
       ("disable-api-write", "disable API write operations")
-      ("dbport", po::value<string>(),
+      ("dbport", po::value<std::string>(),
        "database port number or UNIX socket file name")
-      ("update-dbname", po::value<string>(),
+      ("update-dbname", po::value<std::string>(),
        "database name to use for API write operations, if different from --dbname")
-      ("update-host", po::value<string>(),
+      ("update-host", po::value<std::string>(),
        "database server host for API write operations, if different from --host")
-      ("update-username", po::value<string>(),
+      ("update-username", po::value<std::string>(),
        "database user name for API write operations, if different from --username")
-      ("update-password", po::value<string>(),
+      ("update-password", po::value<std::string>(),
        "database password for API write operations, if different from --password")
-      ("update-charset", po::value<string>(),
+      ("update-charset", po::value<std::string>(),
        "database character set for API write operations, if different from --charset")
-      ("update-dbport", po::value<string>(),
+      ("update-dbport", po::value<std::string>(),
        "database port for API write operations, if different from --dbport");
     // clang-format on
   }
   ~apidb_backend() override = default;
 
-  [[nodiscard]] const string &name() const override { return m_name; }
+  [[nodiscard]] const std::string &name() const override { return m_name; }
   [[nodiscard]] const po::options_description &options() const override { return m_options; }
 
   std::unique_ptr<data_selection::factory> create(const po::variables_map &opts) override {
@@ -61,7 +60,7 @@ struct apidb_backend : public backend {
   }
 
 private:
-  string m_name{"apidb"};
+  std::string m_name{"apidb"};
   po::options_description m_options{"ApiDB backend options"};
 };
 }
diff --git a/src/backend/apidb/changeset.cpp b/src/backend/apidb/changeset.cpp
index ec73d850..c757d908 100644
--- a/src/backend/apidb/changeset.cpp
+++ b/src/backend/apidb/changeset.cpp
@@ -11,13 +11,11 @@
 #include "cgimap/backend/apidb/changeset.hpp"
 #include "cgimap/logger.hpp"
 #include "cgimap/http.hpp"
-#include <map>
-#include <fmt/core.h>
 
-using std::string;
+#include <fmt/core.h>
 
 
-changeset::changeset(bool dp, const string &dn, osm_user_id_t id)
+changeset::changeset(bool dp, const std::string &dn, osm_user_id_t id)
     : data_public(dp), display_name(dn), user_id(id) {}
 
 
diff --git a/src/backend/apidb/readonly_pgsql_selection.cpp b/src/backend/apidb/readonly_pgsql_selection.cpp
index a5d2ecab..0e6af796 100644
--- a/src/backend/apidb/readonly_pgsql_selection.cpp
+++ b/src/backend/apidb/readonly_pgsql_selection.cpp
@@ -23,10 +23,6 @@
 #include <vector>
 
 namespace po = boost::program_options;
-using std::set;
-using std::stringstream;
-using std::list;
-using std::vector;
 
 
 namespace {
@@ -87,7 +83,7 @@ osm_edition_t id_of<osm_edition_t>(const pqxx_tuple &row, pqxx::row_size_type co
 }
 
 template <typename T>
-inline int insert_results(const pqxx::result &res, set<T> &elems) {
+inline int insert_results(const pqxx::result &res, std::set<T> &elems) {
 
   auto const id_col = res.column_number("id");
 
diff --git a/src/fcgi_request.cpp b/src/fcgi_request.cpp
index 52a074ed..1c92a517 100644
--- a/src/fcgi_request.cpp
+++ b/src/fcgi_request.cpp
@@ -24,7 +24,6 @@
 #include <cerrno>
 #include <cstring>
 
-using std::runtime_error;
 
 namespace {
 struct fcgi_buffer : public output_buffer {
@@ -67,10 +66,10 @@ struct fcgi_request::pimpl {
 fcgi_request::fcgi_request(int socket, const std::chrono::system_clock::time_point &now) : m_impl(std::make_unique<pimpl>()) {
   // initialise FCGI
   if (FCGX_Init() != 0) {
-    throw runtime_error("Couldn't initialise FCGX library.");
+    throw std::runtime_error("Couldn't initialise FCGX library.");
   }
   if (FCGX_InitRequest(&m_impl->req, socket, FCGI_FAIL_ACCEPT_ON_INTR) != 0) {
-    throw runtime_error("Couldn't initialise FCGX request structure.");
+    throw std::runtime_error("Couldn't initialise FCGX request structure.");
   }
   m_impl->now = now;
   m_buffer = std::make_unique<fcgi_buffer>(m_impl->req);
@@ -165,7 +164,7 @@ int fcgi_request::accept_r() {
         }
       }
 
-      throw runtime_error(out.str());
+      throw std::runtime_error(out.str());
     }
   }
 
diff --git a/src/http.cpp b/src/http.cpp
index 2d2744a4..d36e65bb 100644
--- a/src/http.cpp
+++ b/src/http.cpp
@@ -21,10 +21,6 @@
 #include <string_view>
 
 
-using std::string;
-using std::vector;
-using std::pair;
-
 namespace {
 /**
  * Functions hexToChar and form_urldecode were taken from GNU CGICC by
@@ -119,7 +115,7 @@ std::string format_header(int status, const headers_t &headers) {
   return hdr;
 }
 
-exception::exception(int c, string m)
+exception::exception(int c, std::string m)
     : code_(c), message_(std::move(m)) {}
 
 int exception::code() const { return code_; }
@@ -128,43 +124,43 @@ const char *exception::header() const { return status_message(code()); }
 
 const char *exception::what() const noexcept { return message_.c_str(); }
 
-server_error::server_error(const string &message)
+server_error::server_error(const std::string &message)
     : exception(500, message) {}
 
-bad_request::bad_request(const string &message)
+bad_request::bad_request(const std::string &message)
     : exception(400, message) {}
 
-forbidden::forbidden(const string &message)
+forbidden::forbidden(const std::string &message)
     : exception(403, message) {}
 
-not_found::not_found(const string &uri)
+not_found::not_found(const std::string &uri)
     : exception(404, uri) {}
 
-not_acceptable::not_acceptable(const string &message)
+not_acceptable::not_acceptable(const std::string &message)
     : exception(406, message) {}
 
-conflict::conflict(const string &message)
+conflict::conflict(const std::string &message)
     : exception(409, message) {}
 
-precondition_failed::precondition_failed(const string &message)
+precondition_failed::precondition_failed(const std::string &message)
     : exception(412, message),
       fullstring("Precondition failed: " + message) {}
 
 const char *precondition_failed::what() const noexcept { return fullstring.c_str(); }
 
-payload_too_large::payload_too_large(const string &message)
+payload_too_large::payload_too_large(const std::string &message)
     : exception(413, message) {}
 
-too_many_requests::too_many_requests(const string &message)
+too_many_requests::too_many_requests(const std::string &message)
     : exception(429, message) {}
 
 bandwidth_limit_exceeded::bandwidth_limit_exceeded(int retry_seconds)
     : exception(509, fmt::format("You have downloaded too much data. Please try again in {} seconds.", retry_seconds)), retry_seconds(retry_seconds) {}
 
-gone::gone(const string &message)
+gone::gone(const std::string &message)
     : exception(410, message) {}
 
-unsupported_media_type::unsupported_media_type(const string &message)
+unsupported_media_type::unsupported_media_type(const std::string &message)
     : exception(415, message) {}
 
 unauthorized::unauthorized(const std::string &message)
@@ -175,9 +171,9 @@ method_not_allowed::method_not_allowed(http::method method)
       allowed_methods(method) {}
 
 
-string urldecode(const string &s) { return form_urldecode(s); }
+std::string urldecode(const std::string &s) { return form_urldecode(s); }
 
-string urlencode(const string &s) {
+std::string urlencode(const std::string &s) {
   static const char hex[] = { '0', '1', '2', '3', '4', '5', '6', '7',
                               '8', '9', 'A', 'B', 'C', 'D', 'E', 'F' };
   std::ostringstream ostr;
@@ -202,9 +198,9 @@ string urlencode(const string &s) {
   return rv;
 }
 
-vector<pair<string, string> > parse_params(const string &p) {
+std::vector<std::pair<std::string, std::string>> parse_params(const std::string &p) {
   // Split the query string into components
-  vector<pair<string, string> > queryKVPairs;
+  std::vector<std::pair<std::string, std::string>> queryKVPairs;
   if (!p.empty()) {
     auto temp = split(p, '&');
 
diff --git a/src/main.cpp b/src/main.cpp
index 6cccf9f4..df0918cc 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -103,23 +103,21 @@ std::string get_generator_string() {
 void get_options(int argc, char **argv, po::variables_map &options) {
   po::options_description desc(PACKAGE_STRING ": Allowed options");
 
-  using std::string;
-
   // clang-format off
   desc.add_options()
     ("help", "display this help and exit")
     ("daemon", "run as a daemon")
     ("instances", po::value<int>()->default_value(5), "number of daemon instances to run")
-    ("pidfile", po::value<string>(), "file to write pid to")
-    ("logfile", po::value<string>(), "file to write log messages to")
-    ("memcache", po::value<string>(), "memcache server specification")
+    ("pidfile", po::value<std::string>(), "file to write pid to")
+    ("logfile", po::value<std::string>(), "file to write log messages to")
+    ("memcache", po::value<std::string>(), "memcache server specification")
     ("ratelimit", po::value<long>(), "average number of bytes/s to allow each client")
     ("moderator-ratelimit", po::value<long>(), "average number of bytes/s to allow each moderator")
     ("maxdebt", po::value<long>(), "maximum debt (in Mb) to allow each client before rate limiting")
     ("moderator-maxdebt", po::value<long>(), "maximum debt (in Mb) to allow each moderator before rate limiting")
     ("port", po::value<int>(), "FCGI port number (e.g. 8000) to listen on. This option is for backwards compatibility, please use --socket for new configurations.")
-    ("socket", po::value<string>(), "FCGI port number (e.g. :8000, or 127.0.0.1:8000) or UNIX domain socket to listen on")
-    ("configfile", po::value<string>(), "Config file")
+    ("socket", po::value<std::string>(), "FCGI port number (e.g. :8000, or 127.0.0.1:8000) or UNIX domain socket to listen on")
+    ("configfile", po::value<std::string>(), "Config file")
     ;
   // clang-format on
 
@@ -133,8 +131,8 @@ void get_options(int argc, char **argv, po::variables_map &options) {
     ("max-payload", po::value<long>(), "max size of HTTP payload allowed for uploads, after decompression (in bytes)")
     ("map-nodes", po::value<int>(), "max number of nodes allowed for /map endpoint")
     ("map-area", po::value<double>(), "max area size allowed for /map endpoint")
-    ("changeset-timeout-open", po::value<string>(), "max open time period for a changeset")
-    ("changeset-timeout-idle", po::value<string>(), "time period a changeset will remain open after last edit")
+    ("changeset-timeout-open", po::value<std::string>(), "max open time period for a changeset")
+    ("changeset-timeout-idle", po::value<std::string>(), "time period a changeset will remain open after last edit")
     ("max-changeset-elements", po::value<int>(), "max number of elements allowed in one changeset")
     ("max-way-nodes", po::value<int>(), "max number of nodes allowed in one way")
     ("scale", po::value<long>(), "conversion factor from double lat/lon to internal int format")
diff --git a/src/osm_changeset_responder.cpp b/src/osm_changeset_responder.cpp
index 9afb9a7d..85d0aae9 100644
--- a/src/osm_changeset_responder.cpp
+++ b/src/osm_changeset_responder.cpp
@@ -12,9 +12,6 @@
 
 #include <fmt/core.h>
 
-#include <optional>
-
-using std::list;
 
 osm_changeset_responder::osm_changeset_responder(mime::type mt,
                                                  data_selection &s,
diff --git a/src/osm_current_responder.cpp b/src/osm_current_responder.cpp
index e2479d0f..6da1b7cf 100644
--- a/src/osm_current_responder.cpp
+++ b/src/osm_current_responder.cpp
@@ -14,7 +14,6 @@
 
 #include <optional>
 
-using std::list;
 
 osm_current_responder::osm_current_responder(mime::type mt, 
                                              data_selection &s,
diff --git a/src/osm_diffresult_responder.cpp b/src/osm_diffresult_responder.cpp
index 821d7c0e..8cdbc9c5 100644
--- a/src/osm_diffresult_responder.cpp
+++ b/src/osm_diffresult_responder.cpp
@@ -13,7 +13,6 @@
 #include <chrono>
 #include <fmt/core.h>
 
-using std::list;
 
 namespace {
 
diff --git a/src/request_helpers.cpp b/src/request_helpers.cpp
index f91ab630..5f731c9c 100644
--- a/src/request_helpers.cpp
+++ b/src/request_helpers.cpp
@@ -16,9 +16,8 @@
 
 #include <fmt/core.h>
 
-using std::string;
 
-string fcgi_get_env(const request &req, const char *name, const char *default_value) {
+std::string fcgi_get_env(const request &req, const char *name, const char *default_value) {
   assert(name);
   const char *v = req.get_param(name);
 
@@ -32,10 +31,10 @@ string fcgi_get_env(const request &req, const char *name, const char *default_va
     }
   }
 
-  return string(v);
+  return std::string(v);
 }
 
-string get_query_string(const request &req) {
+std::string get_query_string(const request &req) {
   // try the query string that's supposed to be present first
   auto *query_string = req.get_param("QUERY_STRING");
 
@@ -95,7 +94,7 @@ std::unique_ptr<http::encoding> get_encoding(const request &req) {
   const char *accept_encoding = req.get_param("HTTP_ACCEPT_ENCODING");
 
   if (accept_encoding) {
-    return http::choose_encoding(string(accept_encoding));
+    return http::choose_encoding(std::string(accept_encoding));
   } else {
     return std::make_unique<http::identity>();
   }
diff --git a/src/text_formatter.cpp b/src/text_formatter.cpp
index c395566f..a8251b18 100644
--- a/src/text_formatter.cpp
+++ b/src/text_formatter.cpp
@@ -11,10 +11,6 @@
 #include <string>
 #include <stdexcept>
 
-using std::string;
-using std::transform;
-
-
 
 text_formatter::text_formatter(std::unique_ptr<text_writer> w) : writer(std::move(w)) {}
 
diff --git a/src/xml_formatter.cpp b/src/xml_formatter.cpp
index 79da53e2..10f56586 100644
--- a/src/xml_formatter.cpp
+++ b/src/xml_formatter.cpp
@@ -11,9 +11,6 @@
 #include <string>
 #include <stdexcept>
 
-using std::string;
-using std::transform;
-
 
 xml_formatter::xml_formatter(std::unique_ptr<xml_writer> w) : writer(std::move(w)) {}