diff --git a/CMakeLists.txt b/CMakeLists.txt
index 6292e4c..3f9ed57 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -32,6 +32,10 @@ add_library(libemory
     emory/fs/ostream.hpp
     emory/fs/xattr.cpp
     emory/fs/xattr.hpp
+    emory/store/bits.cpp
+    emory/store/bits.hpp
+    emory/store/repo.cpp
+    emory/store/repo.hpp
 )
 
 target_link_libraries(libemory cruft acl)
diff --git a/emory/store/bits.cpp b/emory/store/bits.cpp
new file mode 100644
index 0000000..5dc2e2d
--- /dev/null
+++ b/emory/store/bits.cpp
@@ -0,0 +1,13 @@
+/*
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * Copyright 2019 Danny Robson <danny@nerdcruft.net>
+ */
+
+#include "bits.hpp"
+
+
+///////////////////////////////////////////////////////////////////////////////
+
diff --git a/emory/store/bits.hpp b/emory/store/bits.hpp
new file mode 100644
index 0000000..246d204
--- /dev/null
+++ b/emory/store/bits.hpp
@@ -0,0 +1,67 @@
+/*
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * Copyright 2019 Danny Robson <danny@nerdcruft.net>
+ */
+
+#pragma once
+
+#include <cruft/util/std.hpp>
+#include <cruft/crypto/hash/sha1.hpp>
+
+#include <array>
+
+namespace emory::store::bits {
+    constexpr std::array<u08, 8> MAGIC { 'e', 'r', '0', '0', 0x0d, 0x0a, 0x1a, 0x00, };
+
+    struct [[gnu::packed]] header {
+        u08 magic[8];
+        u64 version;
+        struct [[gnu::packed]] {
+            u64 types;
+            u64 records;
+        } entries;
+    };
+
+    bool is_valid (header const&) noexcept;
+
+
+    struct [[gnu::packed]] type {
+        u16 system;
+        u16 index;
+        u08 count;
+        u08 length;
+        u16 reserved;
+    };
+
+
+    namespace record {
+        struct data {
+            cruft::crypto::hash::SHA1::digest_t digest;
+            u64 first;
+            u64 last;
+        };
+    }
+
+
+    constexpr u16 EMORY = 0x0000;
+    constexpr u16 POSIX = 0x0001;
+
+    constexpr type DATA {
+        .system = EMORY,
+        .index = 0x0001,
+        .count = 0,
+        .length = sizeof (record::data),
+        .reserved = 0,
+    };
+
+    constexpr type PATH {
+        .system = POSIX,
+        .index = 0x0001,
+        .count = 0,
+        .length = 0,
+        .reserved = 0,
+    };
+};
diff --git a/emory/store/repo.cpp b/emory/store/repo.cpp
new file mode 100644
index 0000000..a35fead
--- /dev/null
+++ b/emory/store/repo.cpp
@@ -0,0 +1,15 @@
+/*
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * Copyright 2019 Danny Robson <danny@nerdcruft.net>
+ */
+
+#include "repo.hpp"
+
+
+///////////////////////////////////////////////////////////////////////////////
+struct chunker {
+
+};
diff --git a/emory/store/repo.hpp b/emory/store/repo.hpp
new file mode 100644
index 0000000..1676b56
--- /dev/null
+++ b/emory/store/repo.hpp
@@ -0,0 +1,59 @@
+/*
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * Copyright 2019 Danny Robson <danny@nerdcruft.net>
+ */
+
+#pragma once
+
+#include "bits.hpp"
+
+#include <cruft/util/io.hpp>
+
+namespace emory::store {
+    struct repo {
+        repo (cruft::mapped_file &&src);
+
+        cruft::view<bits::type const*> types (void) const;
+
+        struct record_iterator {
+            using iterator_tag = std::input_iterator_tag;
+            using value_type = std::pair<bits::type const&, void*>;
+
+            record_iterator (
+                cruft::view<bits::type const*> _types,
+                cruft::view<u08 const*> _data
+            );
+
+            value_type operator* (void) const;
+
+            record_iterator& operator++ ();
+
+            bool operator== (record_iterator const&) const noexcept;
+            bool operator!= (record_iterator const&) const noexcept;
+
+        private:
+            cruft::view<bits::type const*> m_types;
+            cruft::view<u08 const*> m_data;
+        };
+
+    private:
+        cruft::mapped_file m_src;
+    };
+
+
+    struct serialiser {
+        virtual ~serialiser ();
+
+        virtual bits::type type (void) const;
+        virtual u64 write (cruft::posix::fd &dst, cruft::posix::fd &src);
+        virtual std::ostream& describe (std::ostream&) const;
+    };
+
+
+    u64 send (cruft::posix::fd &dst, cruft::posix::fd &src);
+
+    std::ostream& operator<< (std::ostream&, serialiser const&);
+}