diff --git a/src/Opt.hpp b/src/Opt.hpp
index 2087c42..6c345de 100644
--- a/src/Opt.hpp
+++ b/src/Opt.hpp
@@ -1,59 +1,46 @@
-#include <tclap/ArgException.h>
-#include <tclap/CmdLine.h>
-#include <tclap/StdOutput.h>
-#include <tclap/SwitchArg.h>
-#include <tclap/UnlabeledMultiArg.h>
-#include <tclap/ValueArg.h>
+#pragma once
+
+#include <fmt/core.h>
+#include <fmt/format.h>
 
 #include <filesystem>
-
-template <>
-struct TCLAP::ArgTraits<std::filesystem::path> {
-  typedef ValueLike ValueCategory;
-};
+#include <optional>
+#include <set>
 
 namespace xwim {
 
-namespace fs = std::filesystem;
+enum class Action { EXTRACT, COMPRESS };
 
-class Opt {
- private:
-  // clang-format off
-  TCLAP::CmdLine cmd_line
-    {"xwim - Do What I Mean Extractor", ' ', "0.5.0"};
-
-  TCLAP::SwitchArg arg_compress
-    {"c", "compress", "Compress <files>", cmd_line, false};
-
-  TCLAP::SwitchArg arg_extract
-    {"x", "extract", "Extract <file>", cmd_line, false};
-
-  TCLAP::ValueArg<fs::path> arg_out
-    {"o", "out", "Out <path>", false, fs::path{}, "A path on the filesystem", cmd_line};
-
-  TCLAP::UnlabeledMultiArg<fs::path> arg_paths
-    {"Paths", "Filesystem paths to extract or compress", true, "A path on the filesystem", cmd_line};
-  // clang-format on
-
- public:
-  void parse(int argc, char** argv) { cmd_line.parse(argc, argv); }
-
-  void validate() {
-    if (arg_extract.isSet() && arg_compress.isSet()) {
-      // This is a bit ugly but `none-or-xor` only available in
-      // tclap-1.4 which is not well supported in current
-      // distributions
-      auto out = TCLAP::StdOutput{};
-      TCLAP::ArgException e{
-          "Cannot compress `-c` and extract `-x` simultaneously"};
-
-      try {
-        out.failure(cmd_line, e);
-      } catch (TCLAP::ExitException& e) {
-        exit(e.getExitStatus());
-      }
-    }
-  }
+struct UserOpt {
+  std::optional<Action> action;
+  bool interactive;
+  std::optional<std::filesystem::path> out;
+  std::set<std::filesystem::path> paths;
 };
 
+struct XwimConfig {
+  Action action;
+  std::filesystem::path output;
+  std::set<std::filesystem::path> input;
+};
+
+XwimConfig guess_wim(UserOpt user_opt);
+void do_wim(XwimConfig);
+
 }  // namespace xwim
+
+template <>
+struct fmt::formatter<xwim::Action> {
+  constexpr auto parse(format_parse_context& ctx) { return ctx.begin(); }
+
+  template <typename FormatContext>
+  auto format(const xwim::Action& action, FormatContext& ctx) {
+    switch (action) {
+      case xwim::Action::EXTRACT:
+        return format_to(ctx.out(), "EXTRACT");
+      case xwim::Action::COMPRESS:
+        return format_to(ctx.out(), "COMPRESS");
+    };
+    return format_to(ctx.out(), "");
+  }
+};
diff --git a/src/Xwim.cpp b/src/Xwim.cpp
index ab3160c..b0564e4 100644
--- a/src/Xwim.cpp
+++ b/src/Xwim.cpp
@@ -14,10 +14,6 @@
 #include "Archiver.hpp"
 #include "Common.hpp"
 
-namespace xwim {
-using namespace std;
-namespace fs = std::filesystem;
-
 #if defined(unix) || defined(__unix__) || defined(__unix)
 std::string default_extension = ".tar.gz";
 #elif defined(_win32) || defined(__win32__) || defined(__windows__)
@@ -26,6 +22,10 @@ std::string default_extension = ".zip";
 std::string default_extension = ".zip";
 #endif
 
+namespace xwim {
+using namespace std;
+namespace fs = std::filesystem;
+
 Xwim::Xwim() : action{Action::UNKNOWN} {}
 
 void Xwim::try_infer() {
diff --git a/src/Xwim.hpp b/src/Xwim.hpp
index 6741bb7..318f059 100644
--- a/src/Xwim.hpp
+++ b/src/Xwim.hpp
@@ -9,13 +9,14 @@
 #include <stdexcept>
 
 #include "Common.hpp"
+#include "Opt.hpp"
 #include "Archiver.hpp"
 
 namespace xwim {
 using namespace std;
 namespace fs = std::filesystem;
 
-enum class Action { UNKNOWN, EXTRACT, COMPRESS };
+Xwim xwim(UserOpt user_opt);
 
 class Xwim {
  private:
@@ -43,21 +44,3 @@ class Xwim {
 };
 
 }  // namespace xwim
-
-template <>
-struct fmt::formatter<xwim::Action> {
-  constexpr auto parse(format_parse_context& ctx) { return ctx.begin(); }
-
-  template <typename FormatContext>
-  auto format(const xwim::Action& action, FormatContext& ctx) {
-    switch (action) {
-      case xwim::Action::UNKNOWN:
-        return format_to(ctx.out(), "UNKNOWN");
-      case xwim::Action::EXTRACT:
-        return format_to(ctx.out(), "EXTRACT");
-      case xwim::Action::COMPRESS:
-        return format_to(ctx.out(), "COMPRESS");
-    };
-    return format_to(ctx.out(), "");
-  }
-};
diff --git a/src/main.cpp b/src/main.cpp
index e3e28da..f27b3f1 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -1,31 +1,69 @@
 #include <spdlog/common.h>
 #include <spdlog/logger.h>
 #include <spdlog/spdlog.h>
+#include <tclap/ArgException.h>
+#include <tclap/CmdLine.h>
+#include <tclap/StdOutput.h>
+#include <tclap/SwitchArg.h>
+#include <tclap/UnlabeledMultiArg.h>
+#include <tclap/ValueArg.h>
 
 #include <cstdlib>
 #include <filesystem>
 #include <memory>
+#include <optional>
 
 #include "Common.hpp"
-#include "Opt.hpp"
 #include "Log.hpp"
+#include "Opt.hpp"
 #include "Xwim.hpp"
 
 using namespace xwim;
 using namespace std;
 
+template <>
+struct TCLAP::ArgTraits<std::filesystem::path> {
+  typedef ValueLike ValueCategory;
+};
+
+UserOpt parse_args(int argc, char** argv) {
+  // clang-format off
+  TCLAP::CmdLine cmd_line
+    {"xwim - Do What I Mean Extractor", ' ', "0.5.0"};
+
+  TCLAP::SwitchArg arg_compress
+    {"c", "compress", "Compress <files>", cmd_line, false};
+
+  TCLAP::SwitchArg arg_extract
+    {"x", "extract", "Extract <files>", cmd_line, false};
+
+  TCLAP::SwitchArg arg_noninteractive
+    {"ni", "noninteractive", "Fail if action cannot be determined", cmd_line, false};
+
+  TCLAP::ValueArg<std::filesystem::path> arg_out
+    {"o", "out", "Out <path>", false, std::filesystem::path{}, "A path on the filesystem", cmd_line};
+
+  TCLAP::UnlabeledMultiArg<std::filesystem::path> arg_paths
+    {"Paths", "Filesystem paths to extract or compress", true, "A path on the filesystem", cmd_line};
+  // clang-format on
+
+  cmd_line.parse(argc, argv);
+
+  UserOpt user_opt;
+
+  if(arg_compress.getValue()) user_opt.action = Action::COMPRESS;
+  if(arg_extract.getValue()) user_opt.action = Action::EXTRACT;
+  if(arg_out.isSet()) user_opt.out = arg_out.getValue();
+  user_opt.interactive = !arg_noninteractive.getValue();
+  user_opt.paths = std::set<fs::path>{arg_paths.getValue().begin(), arg_paths.getValue().end()};
+
+  return user_opt;
+}
+
 int main(int argc, char** argv) {
   log::init();
 
-  Opt opt;
-  opt.parse(argc, argv);
-  opt.validate();
-
-  Xwim xwim{};
-
-  try {
-    xwim.dwim();
-  } catch (XwimError& e) {
-    spdlog::error(e.what());
-  }
+  UserOpt user_opt = parse_args(argc, argv);
+  XwimConfig xwim_config = guess_wim(user_opt);
+  do_wim(xwim_config);
 }
diff --git a/src/meson.build b/src/meson.build
index 1f6588c..0062962 100644
--- a/src/meson.build
+++ b/src/meson.build
@@ -1,4 +1,5 @@
 xwim_src = ['main.cpp', 'Xwim.cpp', 'Archiver.cpp']
+xwim_dwim = ['dwim/Opt.cpp']
 xwim_archiver = ['archiver/LibArchiver.cpp']
 
 is_static = get_option('default_library')=='static'
@@ -8,4 +9,6 @@ xwim_libs = [dependency('libarchive', required: true, static: is_static),
              dependency('spdlog', required: true, static: is_static),
              dependency('tclap', required: true, static: is_static)]
 
-executable('xwim', xwim_src+xwim_archiver, dependencies: xwim_libs)
+executable('xwim',
+           xwim_src+xwim_archiver+xwim_dwim,
+           dependencies: xwim_libs)