diff --git a/include/pisa/codec/block_codec_registry.hpp b/include/pisa/codec/block_codec_registry.hpp
index a3b454ea..30583017 100644
--- a/include/pisa/codec/block_codec_registry.hpp
+++ b/include/pisa/codec/block_codec_registry.hpp
@@ -3,13 +3,65 @@
 #include <memory>
 #include <string_view>
 
+#include <fmt/format.h>
 #include <gsl/span>
 
 #include "codec/block_codec.hpp"
+#include "codec/interpolative.hpp"
+#include "codec/maskedvbyte.hpp"
+#include "codec/optpfor.hpp"
+#include "codec/qmx.hpp"
+#include "codec/simdbp.hpp"
+#include "codec/simple16.hpp"
+#include "codec/simple8b.hpp"
+#include "codec/streamvbyte.hpp"
+#include "codec/varint_g8iu.hpp"
+#include "codec/varintgb.hpp"
 
 namespace pisa {
 
-[[nodiscard]] auto get_block_codec(std::string_view name) -> std::unique_ptr<BlockCodec>;
-[[nodiscard]] auto get_block_codec_names() -> gsl::span<std::string_view const>;
+template <typename... C>
+struct BlockCodecRegistry {
+    using BlockCodecConstructor = std::unique_ptr<BlockCodec> (*)();
+
+    constexpr static std::array<std::string_view, sizeof...(C)> names =
+        std::array<std::string_view, sizeof...(C)>{C::name...};
+
+    constexpr static std::array<BlockCodecConstructor, sizeof...(C)> constructors =
+        std::array<BlockCodecConstructor, sizeof...(C)>{[]() -> std::unique_ptr<BlockCodec> {
+            return std::make_unique<C>();
+        }...};
+
+    constexpr static auto count() -> std::size_t { return sizeof...(C); }
+
+    static auto get(std::string_view name) -> std::unique_ptr<BlockCodec> {
+        auto pos = std::find(names.begin(), names.end(), name);
+        if (pos == names.end()) {
+            throw std::domain_error(fmt::format("invalid codec: {}", name));
+        }
+        auto constructor = constructors[std::distance(names.begin(), pos)];
+        return constructor();
+    }
+};
+
+using BlockCodecs = BlockCodecRegistry<
+    InterpolativeBlockCodec,
+    MaskedVByteBlockCodec,
+    OptPForBlockCodec,
+    QmxBlockCodec,
+    SimdBpBlockCodec,
+    Simple16BlockCodec,
+    Simple8bBlockCodec,
+    StreamVByteBlockCodec,
+    VarintG8IUBlockCodec,
+    VarintGbBlockCodec>;
+
+[[nodiscard]] auto get_block_codec(std::string_view name) -> std::unique_ptr<BlockCodec> {
+    return BlockCodecs::get(name);
+}
+
+[[nodiscard]] auto get_block_codec_names() -> gsl::span<std::string_view const> {
+    return gsl::make_span<std::string_view const>(&BlockCodecs::names[0], BlockCodecs::count());
+}
 
 }  // namespace pisa
diff --git a/src/codec/block_codec_registry.cpp b/src/codec/block_codec_registry.cpp
index 2f4b8f12..ab7a880a 100644
--- a/src/codec/block_codec_registry.cpp
+++ b/src/codec/block_codec_registry.cpp
@@ -22,48 +22,4 @@
 
 namespace pisa {
 
-template <typename... C>
-struct BlockCodecRegistry {
-    using BlockCodecConstructor = std::unique_ptr<BlockCodec> (*)();
-
-    constexpr static std::array<std::string_view, sizeof...(C)> names =
-        std::array<std::string_view, sizeof...(C)>{C::name...};
-
-    constexpr static std::array<BlockCodecConstructor, sizeof...(C)> constructors =
-        std::array<BlockCodecConstructor, sizeof...(C)>{[]() -> std::unique_ptr<BlockCodec> {
-            return std::make_unique<C>();
-        }...};
-
-    constexpr static auto count() -> std::size_t { return sizeof...(C); }
-
-    static auto get(std::string_view name) -> std::unique_ptr<BlockCodec> {
-        auto pos = std::find(names.begin(), names.end(), name);
-        if (pos == names.end()) {
-            throw std::domain_error(fmt::format("invalid codec: {}", name));
-        }
-        auto constructor = constructors[std::distance(names.begin(), pos)];
-        return constructor();
-    }
-};
-
-using BlockCodecs = BlockCodecRegistry<
-    InterpolativeBlockCodec,
-    MaskedVByteBlockCodec,
-    OptPForBlockCodec,
-    QmxBlockCodec,
-    SimdBpBlockCodec,
-    Simple16BlockCodec,
-    Simple8bBlockCodec,
-    StreamVByteBlockCodec,
-    VarintG8IUBlockCodec,
-    VarintGbBlockCodec>;
-
-auto get_block_codec(std::string_view name) -> std::unique_ptr<BlockCodec> {
-    return BlockCodecs::get(name);
-}
-
-auto get_block_codec_names() -> gsl::span<std::string_view const> {
-    return gsl::make_span<std::string_view const>(&BlockCodecs::names[0], BlockCodecs::count());
-}
-
 }  // namespace pisa