diff --git a/src/main.cpp b/src/main.cpp
index 20a8233..81d2524 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -126,7 +126,9 @@ int main(int argc, char *argv[])
                 }
 
                 LOG(log::sev::error)
-                    << format(translate("Could not open {0:s}: {1:s}").str(),
+                    << format(translate("Could not open {0:s}: {1:s}")
+                                  .str()
+                                  .c_str(),
                               e.path1(), e.what());
                 return_code = EXIT_FAILURE;
             }
@@ -176,8 +178,10 @@ int main(int argc, char *argv[])
                 {
                     LOG(log::sev::error)
                         << std::strerror(errno) // FIXME: Not thread safe.
-                        << format(translate(" (while opening {0:s})").str(),
-                                  filepath);
+                        << format(translate(" (while opening {0:s})")
+                                      .str()
+                                      .c_str(),
+                                  filepath.c_str());
                     return EXIT_FAILURE;
                 }
                 catch (const boost::regex_error &e)
@@ -233,10 +237,11 @@ int main(int argc, char *argv[])
             while (cancel.wait_for(std::chrono::seconds(opts.status_interval))
                    != std::future_status::ready)
             {
-                std::cerr
-                    << format(translate("{0:d} of {1:d} books searched.").str(),
-                              books_searched, input_files.size())
-                    << '\n';
+                std::cerr << format(translate("{0:d} of {1:d} books searched.")
+                                        .str()
+                                        .c_str(),
+                                    books_searched, input_files.size())
+                          << '\n';
             }
             std::cerr << translate("All books searched.") << '\n';
         }};
diff --git a/src/output.cpp b/src/output.cpp
index dadb3f6..fd6e4f9 100644
--- a/src/output.cpp
+++ b/src/output.cpp
@@ -169,17 +169,18 @@ void html_all(const std::vector<std::vector<search::match>> &matches_all,
         if (!opts.no_fn_epub)
         {
             cout << format(R"(      <th id="file_path_{0:d}">{1:s}</th>)",
-                           count, translate("File path (in EPUB file)"))
+                           count,
+                           translate("File path (in EPUB file)").str().c_str())
                  << '\n';
         }
         cout << format(R"(      <th id="headline_{0:d}">{1:s}</th>)", count,
-                       translate("Last headline"))
+                       translate("Last headline").str().c_str())
              << '\n'
              << format(R"(      <th id="page_{0:d}">{1:s}</th>)", count,
-                       translate("Page number"))
+                       translate("Page number").str().c_str())
              << '\n'
              << format(R"(      <th id="match_{0:d}">{1:s}</th>)", count,
-                       translate("Match"))
+                       translate("Match").str().c_str())
              << "\n    </tr>\n";
 
         for (const auto &match : matches)
diff --git a/src/zip.cpp b/src/zip.cpp
index bb9e778..e52e556 100644
--- a/src/zip.cpp
+++ b/src/zip.cpp
@@ -84,7 +84,7 @@ std::string read_file(const fs::path &filepath, std::string_view entry_path)
                                     "Skipping in-EPUB file.\n")
                               .str()
                               .data(),
-                          filepath);
+                          filepath.c_str());
             continue;
         }
         if (std::strcmp(path, entry_path.data()) == 0)
@@ -99,9 +99,9 @@ std::string read_file(const fs::path &filepath, std::string_view entry_path)
             {
                 close_file(zipfile, filepath);
 
-                throw exception{
-                    format(translate("Could not read {0:s} in {1:s}.").str(),
-                           entry_path, filepath.string())};
+                throw exception{format(
+                    translate("Could not read {0:s} in {1:s}.").str().c_str(),
+                    entry_path, filepath.string())};
             }
 
             close_file(zipfile, filepath);
@@ -115,7 +115,7 @@ std::string read_file(const fs::path &filepath, std::string_view entry_path)
 
     if (entry_path == "META-INF/container.xml")
     { // File is probably not an EPUB.
-        exception e{format(translate("{0:s} not found in {1:s}.").str(),
+        exception e{format(translate("{0:s} not found in {1:s}.").str().c_str(),
                            entry_path, filepath.string())};
         e.code = 1;
         throw exception{e};
@@ -145,7 +145,7 @@ struct archive *open_file(const fs::path &filepath)
     {
         close_file(zipfile, filepath);
 
-        exception e{format(translate("Could not open {0:s}.").str(),
+        exception e{format(translate("Could not open {0:s}.").str().c_str(),
                            filepath.string())};
         e.code = 1;
         throw exception{e};
@@ -159,8 +159,9 @@ void close_file(struct archive *zipfile, const fs::path &filepath)
     auto result{archive_read_free(zipfile)};
     if (result != ARCHIVE_OK)
     {
-        throw exception{format(translate("Could not close {0:s}.").str(),
-                               filepath.string())};
+        throw exception{
+            format(translate("Could not close {0:s}.").str().c_str(),
+                   filepath.string())};
     }
 }