diff --git a/src/libmain/loggers.cc b/src/libmain/loggers.cc
index 41f0b35fb..350f90266 100644
--- a/src/libmain/loggers.cc
+++ b/src/libmain/loggers.cc
@@ -5,7 +5,7 @@ namespace nix {
 
 LogFormat defaultLogFormat = LogFormat::raw;
 
-LogFormat parseLogFormat(const string &logFormatStr) {
+LogFormat parseLogFormat(const std::string & logFormatStr) {
     if (logFormatStr == "raw")
         return LogFormat::raw;
     else if (logFormatStr == "raw-with-logs")
@@ -19,7 +19,7 @@ LogFormat parseLogFormat(const string &logFormatStr) {
     throw Error("option 'log-format' has an invalid value '%s'", logFormatStr);
 }
 
-Logger *makeDefaultLogger() {
+Logger * makeDefaultLogger() {
     switch (defaultLogFormat) {
     case LogFormat::raw:
         return makeSimpleLogger(false);
@@ -34,11 +34,11 @@ Logger *makeDefaultLogger() {
     }
 }
 
-void setLogFormat(const string &logFormatStr) {
+void setLogFormat(const std::string & logFormatStr) {
     setLogFormat(parseLogFormat(logFormatStr));
 }
 
-void setLogFormat(const LogFormat &logFormat) {
+void setLogFormat(const LogFormat & logFormat) {
     defaultLogFormat = logFormat;
     createDefaultLogger();
 }
diff --git a/src/libmain/loggers.hh b/src/libmain/loggers.hh
index f9ba5ee5e..cada03110 100644
--- a/src/libmain/loggers.hh
+++ b/src/libmain/loggers.hh
@@ -12,8 +12,8 @@ enum class LogFormat {
   barWithLogs,
 };
 
-void setLogFormat(const string &logFormatStr);
-void setLogFormat(const LogFormat &logFormat);
+void setLogFormat(const std::string & logFormatStr);
+void setLogFormat(const LogFormat & logFormat);
 
 void createDefaultLogger();
 
diff --git a/src/libmain/progress-bar.cc b/src/libmain/progress-bar.cc
index c9ba89714..b287de8a3 100644
--- a/src/libmain/progress-bar.cc
+++ b/src/libmain/progress-bar.cc
@@ -461,7 +461,7 @@ public:
     }
 };
 
-Logger *makeProgressBar(bool printBuildLogs)
+Logger * makeProgressBar(bool printBuildLogs)
 {
     return new ProgressBar(
         printBuildLogs,
diff --git a/src/libmain/progress-bar.hh b/src/libmain/progress-bar.hh
index 60d0a2076..7f0dafecf 100644
--- a/src/libmain/progress-bar.hh
+++ b/src/libmain/progress-bar.hh
@@ -4,7 +4,7 @@
 
 namespace nix {
 
-Logger* makeProgressBar(bool printBuildLogs = false);
+Logger * makeProgressBar(bool printBuildLogs = false);
 
 void startProgressBar(bool printBuildLogs = false);