diff --git a/src/main.cpp b/src/main.cpp
index 6d1d899..61832de 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -16,9 +16,11 @@
 
 #include "files.hpp"
 #include "fs-compat.hpp"
+#include "log.hpp"
 #include "options.hpp"
 #include "output.hpp"
 #include "search.hpp"
+#include "version.hpp"
 #include "zip.hpp"
 
 #include <boost/locale/generator.hpp>
@@ -48,8 +50,6 @@ int main(int argc, char *argv[])
 
     using boost::locale::translate;
     using fmt::format;
-    using std::cerr;
-    using std::cout;
     using std::string;
     using std::vector;
 
@@ -61,8 +61,12 @@ int main(int argc, char *argv[])
     locale_generator.add_messages_path("/usr/share/locale");
     locale_generator.add_messages_domain("epubgrep");
     std::locale::global(locale_generator(""));
-    cout.imbue(std::locale());
-    cerr.imbue(std::locale());
+    std::cout.imbue(std::locale());
+    std::cerr.imbue(std::locale());
+
+    log::init();
+    auto &lg{log::logger::get()};
+    LOG(lg, log::sev::info) << "epubgrep " << version << " started.";
 
     options::options opts;
     try
@@ -71,8 +75,8 @@ int main(int argc, char *argv[])
     }
     catch (std::exception &e)
     { // Exceptions we can't recover from or ones we don't know.
-        cerr << translate("ERROR: ") << e.what();
-        cerr << translate(" (while parsing options)") << '\n';
+        LOG(lg, log::sev::error)
+            << e.what() << translate(" (while parsing options)");
         return EXIT_FAILURE;
     }
 
@@ -109,10 +113,9 @@ int main(int argc, char *argv[])
                     continue;
                 }
 
-                cerr << translate("ERROR: ")
-                     << format(translate("Could not open {0:s}: {1:s}").str(),
-                               e.path1(), e.what())
-                     << '\n';
+                LOG(lg, log::sev::error)
+                    << format(translate("Could not open {0:s}: {1:s}").str(),
+                              e.path1(), e.what());
                 return_code = EXIT_FAILURE;
             }
         }
@@ -130,8 +133,8 @@ int main(int argc, char *argv[])
     vector<std::future<int>> futurepool;
 
     auto search_file{
-        [&opts, &matches_all, &mutex_matches_all,
-         &search_settings](const fs::path &filepath)
+        [&opts, &matches_all, &mutex_matches_all, &search_settings,
+         &lg](const fs::path &filepath)
         {
             for (const auto &regex : opts.regexp)
             {
@@ -149,25 +152,17 @@ int main(int argc, char *argv[])
                         return EXIT_SUCCESS;
                     }
 
-                    cerr << translate("ERROR: ") << e.what() << '\n';
+                    LOG(lg, log::sev::error) << e.what();
                     return EXIT_FAILURE;
                 }
                 catch (const std::ifstream::failure &e)
                 {
-                    cerr << translate("ERROR: ");
-                    if (e.code() == std::errc::permission_denied)
-                    {
-                        cerr << translate("Permission denied.");
-                    }
-                    else
-                    { // std::ifstream seems to always return a generic error?
-                        cerr << translate("Probably permission denied.") << " ("
-                             << e.what() << ')';
-                    }
-
-                    cerr << format(translate(" (while opening {0:s})").str(),
-                                   filepath)
-                         << '\n';
+                    // std::ifstream seems to always return a generic error?
+                    LOG(lg, log::sev::error)
+                        << translate("Probably permission denied.") << " ("
+                        << e.what() << ')'
+                        << format(translate(" (while opening {0:s})").str(),
+                                  filepath);
                 }
             }
 
diff --git a/src/zip.cpp b/src/zip.cpp
index c2e5594..0407631 100644
--- a/src/zip.cpp
+++ b/src/zip.cpp
@@ -18,6 +18,7 @@
 
 #include "fs-compat.hpp"
 #include "helpers.hpp"
+#include "log.hpp"
 
 #include <archive.h>
 #include <archive_entry.h>
@@ -29,7 +30,6 @@
 #include <cstdlib>
 #include <cstring>
 #include <fstream>
-#include <iostream>
 #include <stdexcept>
 #include <string>
 #include <string_view>
@@ -40,7 +40,6 @@ namespace epubgrep::zip
 
 using boost::locale::translate;
 using fmt::format;
-using std::cerr;
 
 std::vector<std::string> list(const fs::path &filepath)
 {
@@ -53,12 +52,12 @@ std::vector<std::string> list(const fs::path &filepath)
         const auto *in_epub_filepath{archive_entry_pathname_utf8(entry)};
         if (in_epub_filepath == nullptr)
         { // If the encoding is broken, we skip the file.
-            std::cerr << translate("WARNING: ")
-                      << format(translate("File in {0:s} is damaged. "
-                                          "Skipping in-EPUB file.\n")
-                                    .str()
-                                    .data(),
-                                filepath);
+            LOG(log::logger::get(), log::sev::warning)
+                << format(translate("File in {0:s} is damaged. "
+                                    "Skipping in-EPUB file.\n")
+                              .str()
+                              .data(),
+                          filepath);
             continue;
         }
         toc.emplace_back(in_epub_filepath);
@@ -73,6 +72,7 @@ std::vector<std::string> list(const fs::path &filepath)
 std::string read_file(const fs::path &filepath, std::string_view entry_path)
 {
     auto *zipfile{open_file(filepath)};
+    auto &lg{log::logger::get()};
 
     struct archive_entry *entry{};
     while (archive_read_next_header(zipfile, &entry) == ARCHIVE_OK)
@@ -80,12 +80,12 @@ std::string read_file(const fs::path &filepath, std::string_view entry_path)
         const auto *path{archive_entry_pathname_utf8(entry)};
         if (path == nullptr)
         { // If the encoding is broken, we skip the file.
-            std::cerr << translate("WARNING: ")
-                      << format(translate("File in {0:s} is damaged. "
-                                          "Skipping in-EPUB file.\n")
-                                    .str()
-                                    .data(),
-                                filepath);
+            LOG(lg, log::sev::warning)
+                << format(translate("File in {0:s} is damaged. "
+                                    "Skipping in-EPUB file.\n")
+                              .str()
+                              .data(),
+                          filepath);
             continue;
         }
         if (std::strcmp(path, entry_path.data()) == 0)
@@ -122,10 +122,10 @@ std::string read_file(const fs::path &filepath, std::string_view entry_path)
         throw exception{e};
     }
 
-    cerr << translate("WARNING: ")
-         << format(translate("{0:s} not found in {1:s}.").str(), entry_path,
-                   filepath.string())
-         << '\n';
+    LOG(lg, log::sev::warning)
+        << format(translate("{0:s} not found in {1:s}.").str(), entry_path,
+                  filepath.string())
+        << '\n';
     return {};
 }
 
@@ -167,8 +167,10 @@ void close_file(struct archive *zipfile, const fs::path &filepath)
 
 std::vector<std::string> list_spine(const fs::path &filepath)
 {
+    auto &lg{log::logger::get()};
+
     const fs::path opf_file_path{
-        [&filepath]
+        [&filepath, &lg]
         {
             pugi::xml_document xml;
             const std::string container{
@@ -182,7 +184,7 @@ std::vector<std::string> list_spine(const fs::path &filepath)
                     .attribute("full-path")
                     .value();
             }
-            cerr << translate("ERROR: ") << result.description() << '\n';
+            LOG(lg, log::sev::error) << result.description() << '\n';
 
             return "";
         }()};
@@ -223,19 +225,18 @@ std::vector<std::string> list_spine(const fs::path &filepath)
         }
         else
         {
-            cerr << translate("ERROR: ") << "XML: " << result.description()
-                 << '\n';
+            LOG(lg, log::sev::error) << "XML: " << result.description() << '\n';
         }
     }
 
     if (opf_file_path.empty() || spine_filepaths.empty())
     {
-        std::cerr << translate("ERROR: ")
-                  << format(translate("{0:s} is damaged. Could not read spine. "
-                                      "Skipping file.\n")
-                                .str()
-                                .data(),
-                            filepath);
+        LOG(lg, log::sev::error)
+            << format(translate("{0:s} is damaged. Could not read spine. "
+                                "Skipping file.\n")
+                          .str()
+                          .data(),
+                      filepath);
         return {};
     }
 
diff --git a/translations/de.po b/translations/de.po
index 2bd6da1..3dc6417 100644
--- a/translations/de.po
+++ b/translations/de.po
@@ -2,8 +2,8 @@ msgid ""
 msgstr ""
 "Project-Id-Version: epubgrep 0.4.0\n"
 "Report-Msgid-Bugs-To: \n"
-"POT-Creation-Date: 2021-05-30 19:04+0200\n"
-"PO-Revision-Date: 2021-05-30 19:05+0200\n"
+"POT-Creation-Date: 2021-05-31 19:11+0200\n"
+"PO-Revision-Date: 2021-05-31 19:11+0200\n"
 "Last-Translator: tastytea <tastytea@tastytea.de>\n"
 "Language-Team: tastytea <https://schlomp.space/tastytea/epubgrep>\n"
 "Language: de\n"
@@ -17,93 +17,92 @@ msgstr ""
 "X-Poedit-KeywordsList: translate\n"
 "X-Poedit-SearchPath-0: .\n"
 
-#: src/main.cpp:74 src/main.cpp:118 src/main.cpp:158 src/main.cpp:163
-#: src/zip.cpp:184 src/zip.cpp:225 src/zip.cpp:232
-msgid "ERROR: "
-msgstr "FEHLER: "
+#: src/log.cpp:66
+msgid "WARNING"
+msgstr "WARNUNG"
 
-#: src/main.cpp:75
+#: src/log.cpp:70
+msgid "ERROR"
+msgstr "FEHLER"
+
+#: src/main.cpp:79
 msgid " (while parsing options)"
 msgstr " (während Optionen interpretiert wurden)"
 
-#: src/main.cpp:119
+#: src/main.cpp:117
 msgid "Could not open {0:s}: {1:s}"
 msgstr "Konnte {0:s} nicht öffnen: {1:s}"
 
-#: src/main.cpp:166
-msgid "Permission denied."
-msgstr "Erlaubnis verweigert."
-
-#: src/main.cpp:170
+#: src/main.cpp:162
 msgid "Probably permission denied."
 msgstr "Vermutlich Erlaubnis verweigert."
 
-#: src/main.cpp:174
+#: src/main.cpp:164
 msgid " (while opening {0:s})"
 msgstr " (während {0:s} durchsucht wurde)"
 
-#: src/options.cpp:48
+#: src/options.cpp:49
 msgid "Available options"
 msgstr "Verfügbare Optionen"
 
-#: src/options.cpp:52
+#: src/options.cpp:53
 msgid "Display this help and exit."
 msgstr "Diese Hilfe ausgeben und beenden."
 
-#: src/options.cpp:54
+#: src/options.cpp:55
 msgid "Display version information and exit."
 msgstr "Versionsinformationen ausgeben und beenden."
 
-#: src/options.cpp:56
+#: src/options.cpp:57
 msgid "PATTERN is a basic regular expression (default)."
 msgstr "MUSTER ist eine „basic regular expression“ (standard)."
 
-#: src/options.cpp:59
+#: src/options.cpp:60
 msgid "PATTERN is an extended regular expression."
 msgstr "MUSTER ist eine „extended regular expression“."
 
-#: src/options.cpp:61
+#: src/options.cpp:62
 msgid "Use grep-variation of regular expressions with -G and -E."
 msgstr "Benutze grep-Variante von regulären ausdrücken mit -G und -E."
 
-#: src/options.cpp:64
+#: src/options.cpp:65
 msgid "PATTERN is a Perl regular expression."
 msgstr "MUSTER ist ein regulärer Ausdruck, wie Perl ihn akzeptiert."
 
-#: src/options.cpp:66
+#: src/options.cpp:67
 msgid "Ignore case distinctions in pattern and data."
 msgstr "Unterschied zwischen Groß- und Kleinschreibung ignorieren."
 
-#: src/options.cpp:69
+#: src/options.cpp:70
 msgid "PATTERN"
 msgstr "MUSTER"
 
-#: src/options.cpp:70
+#: src/options.cpp:71
 msgid "Use additional PATTERN for matching."
 msgstr "Benutze zusätzliches MUSTER zum Abgleich."
 
-#: src/options.cpp:72
+#: src/options.cpp:73
 msgid "Do not clean up text before searching."
 msgstr "Nicht den Text vor dem suchen säubern."
 
-#: src/options.cpp:74
+#: src/options.cpp:75
 msgid "NUMBER"
 msgstr "ANZAHL"
 
-#: src/options.cpp:75
+#: src/options.cpp:76
 msgid "Print NUMBER words of context around matches."
 msgstr "ANZAHL Wörter an Kontext um die Treffer herum ausgeben."
 
-#: src/options.cpp:77
+#: src/options.cpp:78
 msgid "Turn off colors and other decorations."
 msgstr "Schalte Farben und andere Dekorationen aus."
 
 # Bezieht sich auf --no-filename.
-#: src/options.cpp:79
+#: src/options.cpp:80
 msgid "WHICH"
 msgstr "WELCHE"
 
-#: src/options.cpp:80
+#: src/options.cpp:81
 msgid ""
 "Suppress the mentioning of file names on output. WHICH is ‘filesystem’, ‘in-"
 "epub’ or ‘all’."
@@ -111,24 +110,24 @@ msgstr ""
 "Unterdrücke die Erwähnung der Dateinamens in der Ausgabe. WELCHE kann "
 "‚filesystem‘, ‚in-epub‘ or ‚all‘ sein."
 
-#: src/options.cpp:83
+#: src/options.cpp:84
 msgid "Read all files under each directory, recursively."
 msgstr "Lies rekursiv alle Dateien unter jedem Verzeichnis."
 
-#: src/options.cpp:86
+#: src/options.cpp:87
 msgid "Read all files under each directory, recursively, following symlinks."
 msgstr ""
 "Lies rekursiv alle Dateien unter jedem Verzeichnis und folge dabei symlinks."
 
-#: src/options.cpp:89
+#: src/options.cpp:90
 msgid "Ignore errors about wrong file formats."
 msgstr "Ignoriere Fehlermeldungen wegen des falschen Dateiformats."
 
-#: src/options.cpp:130
+#: src/options.cpp:131
 msgid "Usage: epubgrep [OPTION]… PATTERN [FILE]…\n"
 msgstr "Aufruf: epubgrep [OPTION]… MUSTER [DATEI]…\n"
 
-#: src/options.cpp:132
+#: src/options.cpp:133
 msgid ""
 "\n"
 "You can access the full manual with `man epubgrep`.\n"
@@ -136,7 +135,7 @@ msgstr ""
 "\n"
 "Du kannst mit `man epubgrep` auf das vollständige Handbuch zugreifen.\n"
 
-#: src/options.cpp:139
+#: src/options.cpp:140
 msgid ""
 "Copyright © 2021 tastytea <tastytea@tastytea.de>\n"
 "License AGPL-3.0-only <https://gnu.org/licenses/agpl.html>.\n"
@@ -152,32 +151,28 @@ msgstr ""
 msgid "  In {0:s}: \n"
 msgstr "  In {0:s}:\n"
 
-#: src/zip.cpp:55 src/zip.cpp:82 src/zip.cpp:124
-msgid "WARNING: "
-msgstr "WARNUNG: "
-
-#: src/zip.cpp:56 src/zip.cpp:83
+#: src/zip.cpp:56 src/zip.cpp:84
 msgid "File in {0:s} is damaged. Skipping in-EPUB file.\n"
 msgstr "Datei in {0:s} ist beschädigt. Überspringe Datei in der EPUB.\n"
 
-#: src/zip.cpp:103
+#: src/zip.cpp:104
 msgid "Could not read {0:s} in {1:s}."
 msgstr "Konnte {0:s} in {1:s} nicht lesen."
 
-#: src/zip.cpp:118 src/zip.cpp:125
+#: src/zip.cpp:119 src/zip.cpp:126
 msgid "{0:s} not found in {1:s}."
 msgstr "{0:s} nicht gefunden in {1:s}."
 
-#: src/zip.cpp:148
+#: src/zip.cpp:149
 msgid "Could not open {0:s}."
 msgstr "Konnte {0:s} nicht öffnen."
 
-#: src/zip.cpp:162
+#: src/zip.cpp:163
 msgid "Could not close {0:s}."
 msgstr "Konnte {0:s} nicht schließen."
 
 # „Spine“ ist ein Fachbegriff, daher habe ich ihn nicht übersetzt.
-#: src/zip.cpp:233
+#: src/zip.cpp:235
 msgid "{0:s} is damaged. Could not read spine. Skipping file.\n"
 msgstr ""
 "{0:s} ist beschädigt. Konnte „Spine“ nicht lesen. Überspringe Datei.\n"