diff --git a/CMakeLists.txt b/CMakeLists.txt
index c85cc56..40aec88 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -15,6 +15,8 @@ function(kindle2latex_enable_warnings target)
 endfunction()
 
 add_executable(kindle2latex_typefactory
+  typefactory/converter.cpp
+  typefactory/converter.h
   typefactory/main.cpp
   typefactory/typefactory.h
 )
diff --git a/typefactory/converter.cpp b/typefactory/converter.cpp
new file mode 100644
index 0000000..25a5917
--- /dev/null
+++ b/typefactory/converter.cpp
@@ -0,0 +1,297 @@
+#include "converter.h"
+
+#include <array>
+#include <cerrno>
+#include <cstring>
+#include <fstream>
+#include <iostream>
+#include <stdexcept>
+#include <unordered_map>
+#include <utility>
+#include <vector>
+
+#include "typefactory.h"
+
+static std::string rstrip_cr (std::string s) {
+  if (!s.empty() && s.back() == '\r')
+    s.pop_back();
+  return s;
+}
+
+static std::string latex_escape (const std::string &s) {
+  std::string out;
+  out.reserve (s.size() + s.size() / 8);
+  for (unsigned char ch : s) {
+    switch (ch) {
+      case '\\':
+        out += "\\textbackslash{}";
+        break;
+      case '{':
+        out += "\\{";
+        break;
+      case '}':
+        out += "\\}";
+        break;
+      case '%':
+        out += "\\%";
+        break;
+      case '$':
+        out += "\\$";
+        break;
+      case '#':
+        out += "\\#";
+        break;
+      case '&':
+        out += "\\&";
+        break;
+      case '_':
+        out += "\\_";
+        break;
+      case '^':
+        out += "\\textasciicircum{}";
+        break;
+      case '~':
+        out += "\\textasciitilde{}";
+        break;
+      default:
+        out.push_back (static_cast<char> (ch));
+        break;
+    }
+  }
+  return out;
+}
+
+struct Quote {
+  std::string meta;
+  std::vector<std::string> text_lines;
+};
+
+struct ParseContext {
+  std::vector<std::string> order;
+  std::unordered_map<std::string, std::vector<Quote>> by_title;
+  std::unordered_map<std::string, std::size_t> seen;
+
+  std::string cur_title;
+  std::string cur_meta;
+  std::vector<std::string> cur_text;
+
+  void start_title (std::string title) {
+    cur_title = std::move (title);
+    cur_meta.clear();
+    cur_text.clear();
+  }
+
+  void set_meta (std::string meta) {
+    cur_meta = std::move (meta);
+  }
+
+  void add_text (std::string line) {
+    cur_text.push_back (std::move (line));
+  }
+
+  void finalize_quote() {
+    if (cur_title.empty() || cur_meta.empty()) {
+      cur_meta.clear();
+      cur_text.clear();
+      return;
+    }
+
+    if (seen.find (cur_title) == seen.end()) {
+      seen.emplace (cur_title, order.size());
+      order.push_back (cur_title);
+    }
+
+    by_title[cur_title].push_back (Quote{cur_meta, cur_text});
+
+    cur_meta.clear();
+    cur_text.clear();
+  }
+};
+
+enum class Stage { Title, Meta, Body };
+
+static constexpr std::array<Stage, 3> kAllStages = {
+  Stage::Title, Stage::Meta, Stage::Body
+};
+
+struct ILineHandler {
+  virtual ~ILineHandler() = default;
+
+  virtual void handle (const std::string &line,
+                       ParseContext &ctx,
+                       Stage &next) = 0;
+};
+
+struct TitleHandler final : ILineHandler {
+  void handle (const std::string &line,
+               ParseContext &ctx,
+               Stage &next) override {
+    if (line.empty()) {
+      next = Stage::Title;
+      return;
+    }
+
+    ctx.start_title (line);
+    next = Stage::Meta;
+  }
+};
+
+struct MetaHandler final : ILineHandler {
+  void handle (const std::string &line,
+               ParseContext &ctx,
+               Stage &next) override {
+    ctx.set_meta (line);
+    next = Stage::Body;
+  }
+};
+
+struct BodyHandler final : ILineHandler {
+  void handle (const std::string &line,
+               ParseContext &ctx,
+               Stage &next) override {
+    if (line == "==========") {
+      ctx.finalize_quote();
+      next = Stage::Title;
+      return;
+    }
+
+    ctx.add_text (line);
+    next = Stage::Body;
+  }
+};
+
+using HandlerPtr = std::shared_ptr<ILineHandler>;
+using HandlerMap = std::unordered_map<Stage, HandlerPtr>;
+
+static TypeFactory<Stage, ILineHandler> build_factory() {
+  TypeFactory<Stage, ILineHandler> factory;
+
+  factory.registerType<TitleHandler> (Stage::Title);
+  factory.registerType<MetaHandler> (Stage::Meta);
+  factory.registerType<BodyHandler> (Stage::Body);
+
+  return factory;
+}
+
+static HandlerMap build_handlers_cache (
+  const TypeFactory<Stage, ILineHandler> &factory) {
+
+  HandlerMap handlers;
+  handlers.reserve (kAllStages.size());
+
+  for (Stage stage : kAllStages) {
+    try {
+      auto handler = factory.create (stage);
+      if (!handler)
+        throw std::runtime_error ("Factory returned null handler");
+      handlers.emplace (stage, std::move (handler));
+    } catch (const std::out_of_range &) {
+      throw std::runtime_error ("Missing handler registration for Stage");
+    }
+  }
+
+  if (handlers.size() != kAllStages.size())
+    throw std::runtime_error ("Handler cache size mismatch");
+
+  return handlers;
+}
+
+struct Converter::Impl {
+  ParseContext context;
+};
+
+Converter::Converter (std::string input_file_name)
+  : input_file_name_ (std::move (input_file_name))
+  , impl_ (std::make_unique<Impl>()) {
+}
+
+Converter::~Converter() = default;
+
+int Converter::error_code() const noexcept {
+  return error_code_;
+}
+
+bool Converter::parse() {
+  std::ifstream input (input_file_name_);
+  if (!input.is_open()) {
+    std::cerr << "Failed to open input file: "
+              << input_file_name_
+              << " (" << std::strerror (errno) << ")\n";
+    error_code_ = 2;
+    return false;
+  }
+
+  TypeFactory<Stage, ILineHandler> factory = build_factory();
+
+  HandlerMap handlers;
+  try {
+    handlers = build_handlers_cache (factory);
+  } catch (const std::exception &e) {
+    std::cerr << "Internal error while building handler cache: "
+              << e.what() << "\n";
+    error_code_ = 4;
+    return false;
+  }
+
+  impl_->context = ParseContext{};
+  Stage stage = Stage::Title;
+
+  std::string line;
+  while (std::getline (input, line)) {
+    line = rstrip_cr (std::move (line));
+
+    auto it = handlers.find (stage);
+    if (it == handlers.end() || !it->second) {
+      std::cerr << "Internal error: missing handler at runtime\n";
+      error_code_ = 4;
+      return false;
+    }
+
+    Stage next = stage;
+    it->second->handle (line, impl_->context, next);
+    stage = next;
+  }
+
+  impl_->context.finalize_quote();
+  error_code_ = 0;
+  return true;
+}
+
+bool Converter::save (const std::string &output_file_name) {
+  if (!parse())
+    return false;
+
+  std::ofstream output (output_file_name, std::ios::trunc);
+  if (!output.is_open()) {
+    std::cerr << "Failed to open output file: "
+              << output_file_name
+              << " (" << std::strerror (errno) << ")\n";
+    error_code_ = 3;
+    return false;
+  }
+
+  const ParseContext &ctx = impl_->context;
+  for (std::size_t i = 0; i < ctx.order.size(); ++i) {
+    const auto &title = ctx.order[i];
+    output << "\\section {" << latex_escape (title) << "}\n";
+
+    const auto it = ctx.by_title.find (title);
+    if (it == ctx.by_title.end())
+      continue;
+
+    for (const auto &quote : it->second) {
+      output << "  \\subsection {" << latex_escape (quote.meta) << "}\n";
+
+      for (const auto &text_line : quote.text_lines)
+        output << "    " << latex_escape (text_line) << "\n";
+
+      output << "      \\subsubsection{notes}\n\n";
+    }
+
+    if (i + 1 < ctx.order.size())
+      output << "\n";
+  }
+
+  error_code_ = 0;
+  return true;
+}
diff --git a/typefactory/converter.h b/typefactory/converter.h
new file mode 100644
index 0000000..2420f19
--- /dev/null
+++ b/typefactory/converter.h
@@ -0,0 +1,29 @@
+#ifndef CONVERTER_H
+#define CONVERTER_H
+
+#include <memory>
+#include <string>
+
+class Converter {
+public:
+  explicit Converter (std::string input_file_name);
+  ~Converter();
+
+  Converter (const Converter &) = delete;
+  Converter &operator= (const Converter &) = delete;
+
+  bool save (const std::string &output_file_name);
+  [[nodiscard]] int error_code() const noexcept;
+
+protected:
+  bool parse();
+
+private:
+  struct Impl;
+
+  std::string input_file_name_;
+  std::unique_ptr<Impl> impl_;
+  int error_code_ = 0;
+};
+
+#endif // CONVERTER_H
diff --git a/typefactory/main.cpp b/typefactory/main.cpp
index 61edaf1..8b15481 100644
--- a/typefactory/main.cpp
+++ b/typefactory/main.cpp
@@ -1,231 +1,8 @@
-#include <array>
-#include <cerrno>
-#include <cstring>
-#include <fstream>
 #include <getopt.h>
 #include <iostream>
-#include <stdexcept>
 #include <string>
-#include <unordered_map>
-#include <utility>
-#include <vector>
 
-#include "typefactory.h"
-
-// ------------------------------------------------------------
-// Helpers
-// ------------------------------------------------------------
-
-static std::string rstrip_cr (std::string s) {
-  if (!s.empty() && s.back() == '\r')
-    s.pop_back();
-  return s;
-}
-
-static std::string latex_escape (const std::string &s) {
-  std::string out;
-  out.reserve (s.size() + s.size() / 8);
-  for (unsigned char ch : s) {
-    switch (ch) {
-      case '\\':
-        out += "\\textbackslash{}";
-        break;
-      case '{':
-        out += "\\{";
-        break;
-      case '}':
-        out += "\\}";
-        break;
-      case '%':
-        out += "\\%";
-        break;
-      case '$':
-        out += "\\$";
-        break;
-      case '#':
-        out += "\\#";
-        break;
-      case '&':
-        out += "\\&";
-        break;
-      case '_':
-        out += "\\_";
-        break;
-      case '^':
-        out += "\\textasciicircum{}";
-        break;
-      case '~':
-        out += "\\textasciitilde{}";
-        break;
-      default:
-        out.push_back (static_cast<char> (ch));
-        break;
-    }
-  }
-  return out;
-}
-
-// ------------------------------------------------------------
-// Data model
-// ------------------------------------------------------------
-
-struct Quote {
-  std::string meta;
-  std::vector<std::string> text_lines;
-};
-
-struct ParseContext {
-  std::vector<std::string> order;
-  std::unordered_map<std::string, std::vector<Quote>> by_title;
-  std::unordered_map<std::string, std::size_t> seen;
-
-  std::string cur_title;
-  std::string cur_meta;
-  std::vector<std::string> cur_text;
-
-  void start_title (std::string t) {
-    cur_title = std::move (t);
-    cur_meta.clear();
-    cur_text.clear();
-  }
-
-  void set_meta (std::string m) {
-    cur_meta = std::move (m);
-  }
-  void add_text (std::string line) {
-    cur_text.push_back (std::move (line));
-  }
-
-  void finalize_quote() {
-    // Ignore incomplete entries
-    if (cur_title.empty() || cur_meta.empty()) {
-      cur_meta.clear();
-      cur_text.clear();
-      return;
-    }
-
-    // Preserve insertion order of sections
-    if (seen.find (cur_title) == seen.end()) {
-      seen.emplace (cur_title, order.size());
-      order.push_back (cur_title);
-    }
-
-    by_title[cur_title].push_back (Quote{cur_meta, cur_text});
-
-    cur_meta.clear();
-    cur_text.clear();
-  }
-};
-
-// ------------------------------------------------------------
-// Parsing stages
-// ------------------------------------------------------------
-
-enum class Stage { Title, Meta, Body };
-
-// Explicit list of all supported stages for runtime validation
-static constexpr std::array<Stage, 3> kAllStages = {
-  Stage::Title, Stage::Meta, Stage::Body
-};
-
-struct ILineHandler {
-  virtual ~ILineHandler() = default;
-
-  // Process a single line and decide the next stage
-  virtual void handle (const std::string &line,
-                       ParseContext &ctx,
-                       Stage &next) = 0;
-};
-
-struct TitleHandler final : ILineHandler {
-  void handle (const std::string &line,
-               ParseContext &ctx,
-               Stage &next) override {
-
-    // Skip empty lines between entries
-    if (line.empty()) {
-      next = Stage::Title;
-      return;
-    }
-
-    ctx.start_title (line);
-    next = Stage::Meta;
-  }
-};
-
-struct MetaHandler final : ILineHandler {
-  void handle (const std::string &line,
-               ParseContext &ctx,
-               Stage &next) override {
-
-    ctx.set_meta (line);
-    next = Stage::Body;
-  }
-};
-
-struct BodyHandler final : ILineHandler {
-  void handle (const std::string &line,
-               ParseContext &ctx,
-               Stage &next) override {
-
-    // Separator marks the end of a clipping block
-    if (line == "==========") {
-      ctx.finalize_quote();
-      next = Stage::Title;
-      return;
-    }
-
-    // Keep body lines as-is (including empty ones)
-    ctx.add_text (line);
-    next = Stage::Body;
-  }
-};
-
-// ------------------------------------------------------------
-// Factory wiring + handler caching
-// ------------------------------------------------------------
-
-using HandlerPtr = std::shared_ptr<ILineHandler>;
-using HandlerMap = std::unordered_map<Stage, HandlerPtr>;
-
-static TypeFactory<Stage, ILineHandler> build_factory() {
-  TypeFactory<Stage, ILineHandler> f;
-
-  f.registerType<TitleHandler> (Stage::Title);
-  f.registerType<MetaHandler> (Stage::Meta);
-  f.registerType<BodyHandler> (Stage::Body);
-
-  return f;
-}
-
-static HandlerMap build_handlers_cache (
-  const TypeFactory<Stage, ILineHandler> &factory) {
-
-  HandlerMap handlers;
-  handlers.reserve (kAllStages.size());
-
-  // Runtime validation: ensure each stage has a registered handler
-  for (Stage st : kAllStages) {
-    try {
-      auto h = factory.create (st);
-      if (!h)
-        throw std::runtime_error ("Factory returned null handler");
-      handlers.emplace (st, std::move (h));
-    } catch (const std::out_of_range &) {
-      throw std::runtime_error ("Missing handler registration for Stage");
-    }
-  }
-
-  // Extra consistency check
-  if (handlers.size() != kAllStages.size())
-    throw std::runtime_error ("Handler cache size mismatch");
-
-  return handlers;
-}
-
-// ------------------------------------------------------------
-// CLI handling
-// ------------------------------------------------------------
+#include "converter.h"
 
 struct CliArgs {
   std::string input;
@@ -237,10 +14,7 @@ static void print_usage (const char *argv0) {
             << " --input <file> --output <file>\n";
 }
 
-static bool parse_args (int argc,
-                        char **argv,
-                        CliArgs &out) {
-
+static bool parse_args (int argc, char **argv, CliArgs &out) {
   static option long_opts[] = {
     {"input",  required_argument, nullptr, 'i'},
     {"output", required_argument, nullptr, 'o'},
@@ -249,10 +23,7 @@ static bool parse_args (int argc,
   };
 
   int c = 0;
-  while ((c = ::getopt_long (argc, argv,
-                             "i:o:h",
-                             long_opts,
-                             nullptr)) != -1) {
+  while ((c = ::getopt_long (argc, argv, "i:o:h", long_opts, nullptr)) != -1) {
     switch (c) {
       case 'i':
         out.input = optarg;
@@ -277,91 +48,14 @@ static bool parse_args (int argc,
   return true;
 }
 
-// ------------------------------------------------------------
-// Conversion logic
-// ------------------------------------------------------------
-
-static int convert (const std::string &in_path,
-                    const std::string &out_path) {
-
-  std::ifstream in (in_path);
-  if (!in.is_open()) {
-    std::cerr << "Failed to open input file: "
-              << in_path
-              << " (" << std::strerror (errno) << ")\n";
-    return 2;
-  }
-
-  // Build factory and cache handlers once
-  TypeFactory<Stage, ILineHandler> factory = build_factory();
-
-  HandlerMap handlers;
-  try {
-    handlers = build_handlers_cache (factory);
-  } catch (const std::exception &e) {
-    std::cerr << "Internal error while building handler cache: "
-              << e.what() << "\n";
-    return 4;
-  }
-
-  ParseContext ctx{};
-  Stage stage = Stage::Title;
-
-  std::string line;
-  while (std::getline (in, line)) {
-    line = rstrip_cr (std::move (line));
-
-    auto it = handlers.find (stage);
-    if (it == handlers.end() || !it->second) {
-      std::cerr << "Internal error: missing handler at runtime\n";
-      return 4;
-    }
-
-    Stage next = stage;
-    it->second->handle (line, ctx, next);
-    stage = next;
-  }
-
-  // Ensure the last entry is flushed if file does not end with separator
-  ctx.finalize_quote();
-
-  std::ofstream out (out_path, std::ios::trunc);
-  if (!out.is_open()) {
-    std::cerr << "Failed to open output file: "
-              << out_path
-              << " (" << std::strerror (errno) << ")\n";
-    return 3;
-  }
-
-  // Generate LaTeX output
-  for (std::size_t i = 0; i < ctx.order.size(); ++i) {
-    const auto &title = ctx.order[i];
-    out << "\\section {" << latex_escape (title) << "}\n";
-
-    const auto it = ctx.by_title.find (title);
-    if (it == ctx.by_title.end())
-      continue;
-
-    for (const auto &q : it->second) {
-      out << "  \\subsection {" << latex_escape (q.meta) << "}\n";
-
-      for (const auto &tl : q.text_lines)
-        out << "    " << latex_escape (tl) << "\n";
-
-      out << "      \\subsubsection{notes}\n\n";
-    }
-
-    if (i + 1 < ctx.order.size())
-      out << "\n";
-  }
-
-  return 0;
-}
-
 int main (int argc, char **argv) {
   CliArgs args;
   if (!parse_args (argc, argv, args))
     return 1;
 
-  return convert (args.input, args.output);
+  Converter converter (args.input);
+  if (!converter.save (args.output))
+    return converter.error_code();
+
+  return 0;
 }
diff --git a/typefactory/typefactory.pro b/typefactory/typefactory.pro
index c1c7248..50e73a2 100644
--- a/typefactory/typefactory.pro
+++ b/typefactory/typefactory.pro
@@ -4,7 +4,9 @@ CONFIG -= app_bundle
 CONFIG -= qt
 
 SOURCES += \
+        converter.cpp \
         main.cpp
 
 HEADERS += \
+  converter.h \
   typefactory.h