diff --git a/CMakeLists.txt b/CMakeLists.txt
index db10fbc6..2e4567d7 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -373,6 +373,7 @@ list(
   src/dwarfs/fstypes.cpp
   src/dwarfs/fs_section.cpp
   src/dwarfs/global_entry_data.cpp
+  src/dwarfs/inode_fragments.cpp
   src/dwarfs/inode_manager.cpp
   src/dwarfs/inode_reader_v2.cpp
   src/dwarfs/logger.cpp
diff --git a/include/dwarfs/categorizer.h b/include/dwarfs/categorizer.h
index a8ce4a7c..e3440558 100644
--- a/include/dwarfs/categorizer.h
+++ b/include/dwarfs/categorizer.h
@@ -23,14 +23,14 @@
 
 #include <cstdint>
 #include <filesystem>
+#include <functional>
 #include <limits>
 #include <map>
 #include <memory>
-#include <optional>
 #include <span>
 #include <string_view>
 
-#include "dwarfs/file_category.h"
+#include "dwarfs/inode_fragments.h"
 
 namespace boost::program_options {
 class options_description;
@@ -41,6 +41,9 @@ namespace dwarfs {
 
 class logger;
 
+using category_mapper =
+    std::function<fragment_category::value_type(std::string_view)>;
+
 class categorizer {
  public:
   virtual ~categorizer() = default;
@@ -50,23 +53,26 @@ class categorizer {
 
 class random_access_categorizer : public categorizer {
  public:
-  virtual std::optional<std::string_view>
-  categorize(std::filesystem::path const& path,
-             std::span<uint8_t const> data) const = 0;
+  virtual inode_fragments
+  categorize(std::filesystem::path const& path, std::span<uint8_t const> data,
+             category_mapper const& mapper) const = 0;
 };
 
+// TODO: add call to check if categorizer can return multiple fragments
+//       if it *can* we must run it before we start similarity hashing
 class sequential_categorizer_job {
  public:
   virtual ~sequential_categorizer_job() = default;
 
   virtual void add(std::span<uint8_t const> data) = 0;
-  virtual std::optional<std::string_view> result() = 0;
+  virtual inode_fragments result() = 0;
 };
 
 class sequential_categorizer : public categorizer {
  public:
   virtual std::unique_ptr<sequential_categorizer_job>
-  job(std::filesystem::path const& path, size_t total_size) const = 0;
+  job(std::filesystem::path const& path, size_t total_size,
+      category_mapper const& mapper) const = 0;
 };
 
 class categorizer_job {
@@ -76,6 +82,10 @@ class categorizer_job {
   categorizer_job();
   categorizer_job(std::unique_ptr<impl> impl);
 
+  void set_total_size(size_t total_size) {
+    return impl_->set_total_size(total_size);
+  }
+
   void categorize_random_access(std::span<uint8_t const> data) {
     return impl_->categorize_random_access(data);
   }
@@ -84,7 +94,7 @@ class categorizer_job {
     return impl_->categorize_sequential(data);
   }
 
-  file_category result() { return impl_->result(); }
+  inode_fragments result() { return impl_->result(); }
 
   explicit operator bool() const { return impl_ != nullptr; }
 
@@ -92,9 +102,10 @@ class categorizer_job {
    public:
     virtual ~impl() = default;
 
+    virtual void set_total_size(size_t total_size) = 0;
     virtual void categorize_random_access(std::span<uint8_t const> data) = 0;
     virtual void categorize_sequential(std::span<uint8_t const> data) = 0;
-    virtual file_category result() = 0;
+    virtual inode_fragments result() = 0;
   };
 
  private:
@@ -111,7 +122,7 @@ class categorizer_manager {
     return impl_->job(path);
   }
 
-  std::string_view category_name(file_category c) const {
+  std::string_view category_name(fragment_category::value_type c) const {
     return impl_->category_name(c);
   }
 
@@ -121,7 +132,8 @@ class categorizer_manager {
 
     virtual void add(std::shared_ptr<categorizer const> c) = 0;
     virtual categorizer_job job(std::filesystem::path const& path) const = 0;
-    virtual std::string_view category_name(file_category c) const = 0;
+    virtual std::string_view
+    category_name(fragment_category::value_type c) const = 0;
   };
 
  private:
diff --git a/include/dwarfs/file_category.h b/include/dwarfs/fragment_category.h
similarity index 56%
rename from include/dwarfs/file_category.h
rename to include/dwarfs/fragment_category.h
index 6b56aa2e..4bc307ee 100644
--- a/include/dwarfs/file_category.h
+++ b/include/dwarfs/fragment_category.h
@@ -21,12 +21,13 @@
 
 #pragma once
 
+#include <cassert>
 #include <cstdint>
 #include <limits>
 
 namespace dwarfs {
 
-class file_category {
+class fragment_category {
  public:
   using value_type = uint32_t;
 
@@ -36,37 +37,60 @@ class file_category {
   static constexpr value_type const max{std::numeric_limits<value_type>::max() -
                                         1};
 
-  file_category()
-      : value_{uninitialized} {}
-  file_category(value_type v)
+  fragment_category() = default;
+
+  explicit fragment_category(value_type v)
       : value_{v} {}
 
-  file_category(file_category const&) = default;
-  file_category(file_category&&) = default;
+  fragment_category(value_type v, value_type subcategory)
+      : value_{v}
+      , subcategory_{subcategory} {}
 
-  file_category& operator=(file_category const&) = default;
-  file_category& operator=(file_category&&) = default;
+  fragment_category(fragment_category const&) = default;
+  fragment_category(fragment_category&&) = default;
 
-  file_category& operator=(value_type v) {
+  fragment_category& operator=(fragment_category const&) = default;
+  fragment_category& operator=(fragment_category&&) = default;
+
+  fragment_category& operator=(value_type v) {
+    assert(v != uninitialized);
     value_ = v;
     return *this;
   }
 
   value_type value() const {
-    if (empty()) {
-      throw std::range_error("file_category is uninitialized");
-    }
+    assert(!empty());
     return value_;
   }
 
-  void clear() { value_ = uninitialized; }
+  void clear() {
+    value_ = uninitialized;
+    subcategory_ = uninitialized;
+  }
 
   bool empty() const { return value_ == uninitialized; }
 
   explicit operator bool() const { return !empty(); }
 
+  void set_subcategory(value_type subcategory) {
+    assert(!empty());
+    assert(subcategory != uninitialized);
+    subcategory_ = subcategory;
+  }
+
+  bool has_subcategory() const {
+    return !empty() && subcategory_ != uninitialized;
+  }
+
+  value_type subcategory() const {
+    assert(!empty());
+    assert(subcategory_ != uninitialized);
+    return subcategory_;
+  }
+
  private:
-  value_type value_;
+  value_type value_{uninitialized};
+  value_type subcategory_{uninitialized};
 };
 
 } // namespace dwarfs
diff --git a/include/dwarfs/inode.h b/include/dwarfs/inode.h
index a8d086a5..703e113c 100644
--- a/include/dwarfs/inode.h
+++ b/include/dwarfs/inode.h
@@ -27,7 +27,7 @@
 
 #include <folly/small_vector.h>
 
-#include "dwarfs/file_category.h"
+#include "dwarfs/inode_fragments.h"
 #include "dwarfs/nilsimsa.h"
 #include "dwarfs/object.h"
 
@@ -59,7 +59,7 @@ class inode : public object {
   virtual void add_chunk(size_t block, size_t offset, size_t size) = 0;
   virtual void
   append_chunks_to(std::vector<thrift::metadata::chunk>& vec) const = 0;
-  virtual file_category category() const = 0;
+  virtual inode_fragments const& fragments() const = 0;
 };
 
 } // namespace dwarfs
diff --git a/include/dwarfs/inode_fragments.h b/include/dwarfs/inode_fragments.h
new file mode 100644
index 00000000..31913227
--- /dev/null
+++ b/include/dwarfs/inode_fragments.h
@@ -0,0 +1,83 @@
+/* vim:set ts=2 sw=2 sts=2 et: */
+/**
+ * \author     Marcus Holland-Moritz (github@mhxnet.de)
+ * \copyright  Copyright (c) Marcus Holland-Moritz
+ *
+ * This file is part of dwarfs.
+ *
+ * dwarfs is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * dwarfs is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with dwarfs.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+#pragma once
+
+#include <functional>
+#include <iosfwd>
+#include <span>
+#include <string>
+
+#include <folly/small_vector.h>
+
+#include "dwarfs/fragment_category.h"
+#include "dwarfs/types.h"
+
+namespace dwarfs {
+
+class single_inode_fragment {
+ public:
+  single_inode_fragment(fragment_category category, file_off_t length)
+      : category_{category}
+      , length_{length} {}
+
+  fragment_category category() const { return category_; }
+  file_off_t length() const { return length_; }
+  file_off_t size() const { return length_; }
+
+ private:
+  fragment_category category_;
+  file_off_t length_;
+};
+
+class inode_fragments {
+ public:
+  using mapper_function_type =
+      std::function<std::string(fragment_category::value_type)>;
+
+  inode_fragments() = default;
+
+  single_inode_fragment&
+  emplace_back(fragment_category category, file_off_t length) {
+    return fragments_.emplace_back(category, length);
+  }
+
+  std::span<single_inode_fragment const> span() const { return fragments_; }
+
+  bool empty() const { return fragments_.empty(); }
+
+  explicit operator bool() const { return !empty(); }
+
+  std::ostream&
+  to_stream(std::ostream& os,
+            mapper_function_type const& mapper = mapper_function_type()) const;
+  std::string
+  to_string(mapper_function_type const& mapper = mapper_function_type()) const;
+
+ private:
+  folly::small_vector<single_inode_fragment, 1> fragments_;
+};
+
+inline std::ostream& operator<<(std::ostream& os, inode_fragments const& frag) {
+  return frag.to_stream(os);
+}
+
+} // namespace dwarfs
diff --git a/include/dwarfs/inode_manager.h b/include/dwarfs/inode_manager.h
index 71f64cc9..1678fb53 100644
--- a/include/dwarfs/inode_manager.h
+++ b/include/dwarfs/inode_manager.h
@@ -28,7 +28,7 @@
 #include <utility>
 #include <vector>
 
-#include "dwarfs/file_category.h"
+#include "dwarfs/fragment_category.h"
 
 namespace dwarfs {
 
@@ -59,7 +59,8 @@ class inode_manager {
     impl_->for_each_inode_in_order(fn);
   }
 
-  std::vector<std::pair<file_category, size_t>> category_counts() const {
+  std::vector<std::pair<fragment_category::value_type, size_t>>
+  category_counts() const {
     return impl_->category_counts();
   }
 
@@ -74,7 +75,7 @@ class inode_manager {
                  file_order_options const& file_order, order_cb const& fn) = 0;
     virtual void for_each_inode_in_order(
         std::function<void(std::shared_ptr<inode> const&)> const& fn) const = 0;
-    virtual std::vector<std::pair<file_category, size_t>>
+    virtual std::vector<std::pair<fragment_category::value_type, size_t>>
     category_counts() const = 0;
   };
 
diff --git a/src/dwarfs/categorizer.cpp b/src/dwarfs/categorizer.cpp
index 969bbeb0..067100c0 100644
--- a/src/dwarfs/categorizer.cpp
+++ b/src/dwarfs/categorizer.cpp
@@ -35,19 +35,20 @@
 
 namespace dwarfs {
 
+using namespace std::placeholders;
+
 namespace po = boost::program_options;
 
 namespace {
 constexpr std::string_view const DEFAULT_CATEGORY{"<default>"};
 }
 
-class categorizer_manager_private {
+class categorizer_manager_private : public categorizer_manager::impl {
  public:
-  virtual ~categorizer_manager_private() = default;
-
   virtual std::vector<std::shared_ptr<categorizer const>> const&
   categorizers() const = 0;
-  virtual file_category category(std::string_view cat) const = 0;
+  virtual fragment_category::value_type
+  category(std::string_view cat) const = 0;
 };
 
 template <typename LoggerPolicy>
@@ -57,39 +58,48 @@ class categorizer_job_ final : public categorizer_job::impl {
                    std::filesystem::path const& path)
       : LOG_PROXY_INIT(lgr)
       , mgr_{mgr}
-      , path_{path} {}
+      , path_{path}
+      , cat_mapper_{std::bind(&categorizer_manager_private::category,
+                              std::cref(mgr_), _1)} {}
 
+  void set_total_size(size_t total_size) override;
   void categorize_random_access(std::span<uint8_t const> data) override;
   void categorize_sequential(std::span<uint8_t const> data) override;
-  file_category result() override;
+  inode_fragments result() override;
 
  private:
   LOG_PROXY_DECL(LoggerPolicy);
   categorizer_manager_private const& mgr_;
 
-  std::string_view best_{DEFAULT_CATEGORY};
+  inode_fragments best_;
   int index_{-1};
   bool is_global_best_{false};
-  size_t total_size_hint_{0};
+  size_t total_size_{0};
   std::vector<std::pair<int, std::unique_ptr<sequential_categorizer_job>>>
       seq_jobs_;
   std::filesystem::path const path_;
+  category_mapper cat_mapper_;
 };
 
+template <typename LoggerPolicy>
+void categorizer_job_<LoggerPolicy>::set_total_size(size_t total_size) {
+  total_size_ = total_size;
+}
+
 template <typename LoggerPolicy>
 void categorizer_job_<LoggerPolicy>::categorize_random_access(
     std::span<uint8_t const> data) {
   DWARFS_CHECK(index_ < 0,
                "internal error: index already set in categorize_random_access");
 
-  total_size_hint_ = data.size();
+  total_size_ = data.size();
 
   bool global_best = true;
 
   for (auto&& [index, cat] : folly::enumerate(mgr_.categorizers())) {
     if (auto p = dynamic_cast<random_access_categorizer const*>(cat.get())) {
-      if (auto c = p->categorize(path_, data)) {
-        best_ = *c;
+      if (auto c = p->categorize(path_, data, cat_mapper_)) {
+        best_ = c;
         index_ = index;
         is_global_best_ = global_best;
         break;
@@ -114,7 +124,7 @@ void categorizer_job_<LoggerPolicy>::categorize_sequential(
       }
 
       if (auto p = dynamic_cast<sequential_categorizer const*>(cat.get())) {
-        if (auto job = p->job(path_, total_size_hint_)) {
+        if (auto job = p->job(path_, total_size_, cat_mapper_)) {
           seq_jobs_.emplace_back(index, std::move(job));
         }
       }
@@ -127,12 +137,12 @@ void categorizer_job_<LoggerPolicy>::categorize_sequential(
 }
 
 template <typename LoggerPolicy>
-file_category categorizer_job_<LoggerPolicy>::result() {
+inode_fragments categorizer_job_<LoggerPolicy>::result() {
   if (!seq_jobs_.empty()) {
     for (auto&& [index, job] : seq_jobs_) {
       if (auto c = job->result()) {
         assert(index_ < 0 || index < index_);
-        best_ = *c;
+        best_ = c;
         break;
       }
     }
@@ -140,9 +150,12 @@ file_category categorizer_job_<LoggerPolicy>::result() {
     seq_jobs_.clear();
   }
 
-  LOG_TRACE << path_ << " -> " << best_;
+  LOG_TRACE << path_ << " -> "
+            << best_.to_string([this](fragment_category::value_type c) {
+                 return std::string(mgr_.category_name(c));
+               });
 
-  return mgr_.category(best_);
+  return best_;
 }
 
 categorizer_job::categorizer_job() = default;
@@ -151,8 +164,7 @@ categorizer_job::categorizer_job(std::unique_ptr<impl> impl)
     : impl_{std::move(impl)} {}
 
 template <typename LoggerPolicy>
-class categorizer_manager_ final : public categorizer_manager::impl,
-                                   public categorizer_manager_private {
+class categorizer_manager_ final : public categorizer_manager_private {
  public:
   categorizer_manager_(logger& lgr)
       : lgr_{lgr}
@@ -162,14 +174,15 @@ class categorizer_manager_ final : public categorizer_manager::impl,
 
   void add(std::shared_ptr<categorizer const> c) override;
   categorizer_job job(std::filesystem::path const& path) const override;
-  std::string_view category_name(file_category c) const override;
+  std::string_view
+  category_name(fragment_category::value_type c) const override;
 
   std::vector<std::shared_ptr<categorizer const>> const&
   categorizers() const override {
     return categorizers_;
   }
 
-  file_category category(std::string_view cat) const override {
+  fragment_category::value_type category(std::string_view cat) const override {
     auto it = catmap_.find(cat);
     DWARFS_CHECK(it != catmap_.end(), fmt::format("unknown category: {}", cat));
     return it->second;
@@ -188,7 +201,7 @@ class categorizer_manager_ final : public categorizer_manager::impl,
   LOG_PROXY_DECL(LoggerPolicy);
   std::vector<std::shared_ptr<categorizer const>> categorizers_;
   std::vector<std::string_view> categories_;
-  std::unordered_map<std::string_view, file_category> catmap_;
+  std::unordered_map<std::string_view, fragment_category::value_type> catmap_;
 };
 
 template <typename LoggerPolicy>
@@ -210,9 +223,9 @@ categorizer_job categorizer_manager_<LoggerPolicy>::job(
 }
 
 template <typename LoggerPolicy>
-std::string_view
-categorizer_manager_<LoggerPolicy>::category_name(file_category c) const {
-  return DWARFS_NOTHROW(categories_.at(c.value()));
+std::string_view categorizer_manager_<LoggerPolicy>::category_name(
+    fragment_category::value_type c) const {
+  return DWARFS_NOTHROW(categories_.at(c));
 }
 
 categorizer_manager::categorizer_manager(logger& lgr)
diff --git a/src/dwarfs/categorizer/binary_categorizer.cpp b/src/dwarfs/categorizer/binary_categorizer.cpp
index c7c2dc58..075cb85a 100644
--- a/src/dwarfs/categorizer/binary_categorizer.cpp
+++ b/src/dwarfs/categorizer/binary_categorizer.cpp
@@ -58,9 +58,9 @@ class binary_categorizer_ final : public binary_categorizer_base {
   binary_categorizer_(logger& lgr)
       : LOG_PROXY_INIT(lgr) {}
 
-  std::optional<std::string_view>
-  categorize(std::filesystem::path const& path,
-             std::span<uint8_t const> data) const override;
+  inode_fragments
+  categorize(std::filesystem::path const& path, std::span<uint8_t const> data,
+             category_mapper const& mapper) const override;
 
  private:
   LOG_PROXY_DECL(LoggerPolicy);
@@ -74,10 +74,12 @@ std::span<std::string_view const> binary_categorizer_base::categories() const {
 }
 
 template <typename LoggerPolicy>
-std::optional<std::string_view>
-binary_categorizer_<LoggerPolicy>::categorize(std::filesystem::path const&,
-                                              std::span<uint8_t const> data
-                                              [[maybe_unused]]) const {
+inode_fragments binary_categorizer_<LoggerPolicy>::categorize(
+    std::filesystem::path const&,
+    std::span<uint8_t const> data [[maybe_unused]],
+    category_mapper const& /*mapper*/) const {
+  inode_fragments fragments;
+
 #ifndef _WIN32
   auto p = data.data();
   if (data.size() >= EI_NIDENT && ::memcmp(p, ELFMAG, 4) == 0) {
@@ -101,7 +103,7 @@ binary_categorizer_<LoggerPolicy>::categorize(std::filesystem::path const&,
   }
 #endif
 
-  return std::nullopt;
+  return fragments;
 }
 
 class binary_categorizer_factory : public categorizer_factory {
diff --git a/src/dwarfs/categorizer/incompressible_categorizer.cpp b/src/dwarfs/categorizer/incompressible_categorizer.cpp
index 665b4cf6..976b2b05 100644
--- a/src/dwarfs/categorizer/incompressible_categorizer.cpp
+++ b/src/dwarfs/categorizer/incompressible_categorizer.cpp
@@ -57,10 +57,12 @@ class incompressible_categorizer_job_ : public sequential_categorizer_job {
   incompressible_categorizer_job_(logger& lgr,
                                   incompressible_categorizer_config const& cfg,
                                   std::filesystem::path const& path,
-                                  size_t total_size)
+                                  size_t total_size,
+                                  category_mapper const& mapper)
       : LOG_PROXY_INIT(lgr)
       , cfg_{cfg}
-      , path_{path} {
+      , path_{path}
+      , mapper_{mapper} {
     input_.reserve(total_size < block_size ? total_size : block_size);
     state_ = ::malloc(LZ4_sizeofState());
   }
@@ -77,7 +79,8 @@ class incompressible_categorizer_job_ : public sequential_categorizer_job {
     }
   }
 
-  std::optional<std::string_view> result() override {
+  inode_fragments result() override {
+    inode_fragments fragments;
     if (!input_.empty()) {
       compress();
     }
@@ -88,9 +91,11 @@ class incompressible_categorizer_job_ : public sequential_categorizer_job {
     if (total_blocks_ > 0 &&
         (total_output_size_ >= cfg_.max_ratio_size * total_input_size_ ||
          incompressible_blocks_ >= cfg_.max_ratio_blocks * total_blocks_)) {
-      return INCOMPRESSIBLE_CATEGORY;
+      fragments.emplace_back(
+          fragment_category(mapper_(INCOMPRESSIBLE_CATEGORY)),
+          total_input_size_);
     }
-    return std::nullopt;
+    return fragments;
   }
 
  private:
@@ -139,6 +144,7 @@ class incompressible_categorizer_job_ : public sequential_categorizer_job {
   size_t incompressible_blocks_{0};
   incompressible_categorizer_config const& cfg_;
   std::filesystem::path const& path_;
+  category_mapper const& mapper_;
 };
 
 class incompressible_categorizer_ final : public sequential_categorizer {
@@ -148,7 +154,8 @@ class incompressible_categorizer_ final : public sequential_categorizer {
 
   std::span<std::string_view const> categories() const override;
   std::unique_ptr<sequential_categorizer_job>
-  job(std::filesystem::path const& path, size_t total_size) const override;
+  job(std::filesystem::path const& path, size_t total_size,
+      category_mapper const& mapper) const override;
 
  private:
   logger& lgr_;
@@ -170,7 +177,8 @@ incompressible_categorizer_::categories() const {
 
 std::unique_ptr<sequential_categorizer_job>
 incompressible_categorizer_::job(std::filesystem::path const& path,
-                                 size_t total_size) const {
+                                 size_t total_size,
+                                 category_mapper const& mapper) const {
   if (total_size < config_.min_input_size) {
     return nullptr;
   }
@@ -178,7 +186,7 @@ incompressible_categorizer_::job(std::filesystem::path const& path,
   return make_unique_logging_object<sequential_categorizer_job,
                                     incompressible_categorizer_job_,
                                     logger_policies>(lgr_, config_, path,
-                                                     total_size);
+                                                     total_size, mapper);
 }
 
 class incompressible_categorizer_factory : public categorizer_factory {
diff --git a/src/dwarfs/categorizer/libmagic_categorizer.cpp b/src/dwarfs/categorizer/libmagic_categorizer.cpp
index c26b961c..47324906 100644
--- a/src/dwarfs/categorizer/libmagic_categorizer.cpp
+++ b/src/dwarfs/categorizer/libmagic_categorizer.cpp
@@ -143,9 +143,9 @@ class libmagic_categorizer_ final : public libmagic_categorizer_base {
     }
   }
 
-  std::optional<std::string_view>
-  categorize(std::filesystem::path const& path,
-             std::span<uint8_t const> data) const override;
+  inode_fragments
+  categorize(std::filesystem::path const& path, std::span<uint8_t const> data,
+             category_mapper const& mapper) const override;
 
  private:
   LOG_PROXY_DECL(LoggerPolicy);
@@ -162,15 +162,17 @@ libmagic_categorizer_base::categories() const {
 }
 
 template <typename LoggerPolicy>
-std::optional<std::string_view> libmagic_categorizer_<LoggerPolicy>::categorize(
-    std::filesystem::path const& path, std::span<uint8_t const> data) const {
+inode_fragments libmagic_categorizer_<LoggerPolicy>::categorize(
+    std::filesystem::path const& path, std::span<uint8_t const> data,
+    category_mapper const& /*mapper*/) const {
+  inode_fragments fragments; // TODO: actually fill this :-)
   auto id = m_.identify(data);
   LOG_DEBUG << path << " -> (magic) " << id;
   {
     auto wlock = mimetypes_.wlock();
     ++(*wlock)[id];
   }
-  return std::nullopt;
+  return fragments;
 }
 
 class libmagic_categorizer_factory : public categorizer_factory {
diff --git a/src/dwarfs/inode_fragments.cpp b/src/dwarfs/inode_fragments.cpp
new file mode 100644
index 00000000..a09721a6
--- /dev/null
+++ b/src/dwarfs/inode_fragments.cpp
@@ -0,0 +1,74 @@
+/* vim:set ts=2 sw=2 sts=2 et: */
+/**
+ * \author     Marcus Holland-Moritz (github@mhxnet.de)
+ * \copyright  Copyright (c) Marcus Holland-Moritz
+ *
+ * This file is part of dwarfs.
+ *
+ * dwarfs is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * dwarfs is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with dwarfs.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+#include <ostream>
+#include <sstream>
+
+#include "dwarfs/inode_fragments.h"
+
+namespace dwarfs {
+
+std::ostream&
+inode_fragments::to_stream(std::ostream& os,
+                           mapper_function_type const& mapper) const {
+  if (empty()) {
+    os << "(empty)";
+  } else {
+    os << "[";
+    bool first = true;
+
+    for (auto const& f : span()) {
+      if (first) {
+        first = false;
+      } else {
+        os << ", ";
+      }
+
+      os << "(";
+
+      auto const& cat = f.category();
+      if (mapper) {
+        os << mapper(cat.value());
+      } else {
+        os << cat.value();
+      }
+
+      if (cat.has_subcategory()) {
+        os << "/" << cat.subcategory();
+      }
+
+      os << ", " << f.size() << ")";
+    }
+
+    os << "]";
+  }
+
+  return os;
+}
+
+std::string
+inode_fragments::to_string(mapper_function_type const& mapper) const {
+  std::ostringstream oss;
+  to_stream(oss, mapper);
+  return oss.str();
+}
+
+} // namespace dwarfs
diff --git a/src/dwarfs/inode_manager.cpp b/src/dwarfs/inode_manager.cpp
index 3d05bce0..44eb7e2d 100644
--- a/src/dwarfs/inode_manager.cpp
+++ b/src/dwarfs/inode_manager.cpp
@@ -155,6 +155,7 @@ class inode_ : public inode {
 
     if (mm) {
       if (catjob) {
+        catjob.set_total_size(mm->size());
         catjob.categorize_random_access(mm->span());
       }
 
@@ -201,7 +202,7 @@ class inode_ : public inode {
     }
 
     if (catjob) {
-      category_ = catjob.result();
+      fragments_ = catjob.result();
     }
   }
 
@@ -228,12 +229,14 @@ class inode_ : public inode {
     vec.insert(vec.end(), chunks_.begin(), chunks_.end());
   }
 
-  file_category category() const override { return category_; }
+  inode_fragments const& fragments() const override { return fragments_; }
 
  private:
+  // TODO: can we move optional stuff (e.g. nilsimsa_similarity_hash_) out of
+  // here?
   std::optional<uint32_t> num_;
   uint32_t similarity_hash_{0};
-  file_category category_;
+  inode_fragments fragments_;
   files_vector files_;
   std::vector<chunk_type> chunks_;
   nilsimsa::hash_type nilsimsa_similarity_hash_;
@@ -278,23 +281,26 @@ class inode_manager_ final : public inode_manager::impl {
     }
   }
 
-  std::vector<std::pair<file_category, size_t>>
+  std::vector<std::pair<fragment_category::value_type, size_t>>
   category_counts() const override {
-    std::unordered_map<file_category::value_type, size_t> tmp;
+    std::unordered_map<fragment_category::value_type, size_t> tmp;
 
     for (auto const& i : inodes_) {
-      ++tmp[i->category().value()];
+      if (auto const& fragments = i->fragments(); !fragments.empty()) {
+        for (auto const& frag : fragments.span()) {
+          ++tmp[frag.category().value()];
+        }
+      }
     }
 
-    std::vector<std::pair<file_category, size_t>> rv;
+    std::vector<std::pair<fragment_category::value_type, size_t>> rv;
 
     for (auto const& [k, v] : tmp) {
       rv.emplace_back(k, v);
     }
 
-    std::sort(rv.begin(), rv.end(), [](auto const& a, auto const& b) {
-      return a.first.value() < b.first.value();
-    });
+    std::sort(rv.begin(), rv.end(),
+              [](auto const& a, auto const& b) { return a.first < b.first; });
 
     return rv;
   }