diff --git a/aos/logging/implementations.cc b/aos/logging/implementations.cc
new file mode 100644
index 0000000..337aa8f
--- /dev/null
+++ b/aos/logging/implementations.cc
@@ -0,0 +1,437 @@
+#include "aos/logging/implementations.h"
+
+#include <stdarg.h>
+#include <inttypes.h>
+
+#include <algorithm>
+#include <chrono>
+
+#include "aos/die.h"
+#include "aos/logging/printf_formats.h"
+#include "aos/queue_types.h"
+#include "aos/time/time.h"
+#include "aos/linux_code/ipc_lib/queue.h"
+#include "aos/once.h"
+
+namespace aos {
+namespace logging {
+namespace {
+
+namespace chrono = ::std::chrono;
+
+// The root LogImplementation. It only logs to stderr/stdout.
+// Some of the things specified in the LogImplementation documentation doesn't
+// apply here (mostly the parts about being able to use LOG) because this is the
+// root one.
+class RootLogImplementation : public SimpleLogImplementation {
+ public:
+  void have_other_implementation() { only_implementation_ = false; }
+
+ private:
+  void set_next(LogImplementation *) override {
+    LOG(FATAL, "can't have a next logger from here\n");
+  }
+
+  __attribute__((format(GOOD_PRINTF_FORMAT_TYPE, 3, 0)))
+  void DoLog(log_level level, const char *format, va_list ap) override {
+    LogMessage message;
+    internal::FillInMessage(level, format, ap, &message);
+    internal::PrintMessage(stderr, message);
+    if (!only_implementation_) {
+      fputs("root logger got used, see stderr for message\n", stdout);
+    }
+  }
+
+  bool only_implementation_ = true;
+};
+
+RootLogImplementation *root_implementation = nullptr;
+
+void SetGlobalImplementation(LogImplementation *implementation) {
+  if (root_implementation == nullptr) {
+    fputs("Somebody didn't call logging::Init()!\n", stderr);
+    abort();
+  }
+
+  internal::Context *context = internal::Context::Get();
+
+  context->implementation = implementation;
+  internal::global_top_implementation.store(implementation);
+}
+
+void NewContext() {
+  internal::Context::Delete();
+}
+
+void *DoInit() {
+  SetGlobalImplementation(root_implementation = new RootLogImplementation());
+
+  if (pthread_atfork(NULL /*prepare*/, NULL /*parent*/,
+                     NewContext /*child*/) != 0) {
+    LOG(FATAL, "pthread_atfork(NULL, NULL, %p) failed\n",
+        NewContext);
+  }
+
+  return NULL;
+}
+
+}  // namespace
+namespace internal {
+namespace {
+
+void FillInMessageBase(log_level level, LogMessage *message) {
+  Context *context = Context::Get();
+
+  message->level = level;
+  message->source = context->source;
+  memcpy(message->name, context->name, context->name_size);
+  message->name_length = context->name_size;
+
+  monotonic_clock::time_point monotonic_now = monotonic_clock::now();
+  message->seconds =
+      chrono::duration_cast<chrono::seconds>(monotonic_now.time_since_epoch())
+          .count();
+  message->nseconds =
+      chrono::duration_cast<chrono::nanoseconds>(
+          monotonic_now.time_since_epoch() - chrono::seconds(message->seconds))
+          .count();
+
+  message->sequence = context->sequence++;
+}
+
+}  // namespace
+
+void FillInMessageStructure(log_level level,
+                            const ::std::string &message_string, size_t size,
+                            const MessageType *type,
+                            const ::std::function<size_t(char *)> &serialize,
+                            LogMessage *message) {
+  type_cache::AddShm(type->id);
+  message->structure.type_id = type->id;
+
+  FillInMessageBase(level, message);
+
+  if (message_string.size() + size > sizeof(message->structure.serialized)) {
+    LOG(FATAL, "serialized struct %s (size %zd) and message %s too big\n",
+        type->name.c_str(), size, message_string.c_str());
+  }
+  message->structure.string_length = message_string.size();
+  memcpy(message->structure.serialized, message_string.data(),
+         message->structure.string_length);
+
+  message->message_length = serialize(
+      &message->structure.serialized[message->structure.string_length]);
+  message->type = LogMessage::Type::kStruct;
+}
+
+void FillInMessageMatrix(log_level level,
+                         const ::std::string &message_string, uint32_t type_id,
+                         int rows, int cols, const void *data,
+                         LogMessage *message) {
+  CHECK(MessageType::IsPrimitive(type_id));
+  message->matrix.type = type_id;
+
+  const auto element_size = MessageType::Sizeof(type_id);
+
+  FillInMessageBase(level, message);
+
+  message->message_length = rows * cols * element_size;
+  if (message_string.size() + message->message_length >
+      sizeof(message->matrix.data)) {
+    LOG(FATAL, "%dx%d matrix of type %" PRIu32
+               " (size %u) and message %s is too big\n",
+        rows, cols, type_id, element_size, message_string.c_str());
+  }
+  message->matrix.string_length = message_string.size();
+  memcpy(message->matrix.data, message_string.data(),
+         message->matrix.string_length);
+
+  message->matrix.rows = rows;
+  message->matrix.cols = cols;
+  SerializeMatrix(type_id, &message->matrix.data[message->matrix.string_length],
+                  data, rows, cols);
+  message->type = LogMessage::Type::kMatrix;
+}
+
+void FillInMessage(log_level level, const char *format, va_list ap,
+                   LogMessage *message) {
+  FillInMessageBase(level, message);
+
+  message->message_length =
+      ExecuteFormat(message->message, sizeof(message->message), format, ap);
+  message->type = LogMessage::Type::kString;
+}
+
+void PrintMessage(FILE *output, const LogMessage &message) {
+#define BASE_ARGS                                                              \
+  AOS_LOGGING_BASE_ARGS(                                                       \
+      message.name_length, message.name, static_cast<int32_t>(message.source), \
+      message.sequence, message.level, message.seconds, message.nseconds)
+  switch (message.type) {
+    case LogMessage::Type::kString:
+      fprintf(output, AOS_LOGGING_BASE_FORMAT "%.*s", BASE_ARGS,
+              static_cast<int>(message.message_length), message.message);
+      break;
+    case LogMessage::Type::kStruct: {
+      char buffer[4096];
+      size_t output_length = sizeof(buffer);
+      size_t input_length = message.message_length;
+      if (!PrintMessage(
+              buffer, &output_length,
+              message.structure.serialized + message.structure.string_length,
+              &input_length, type_cache::Get(message.structure.type_id))) {
+        LOG(FATAL,
+            "printing message (%.*s) of type %s into %zu-byte buffer failed\n",
+            static_cast<int>(message.message_length), message.message,
+            type_cache::Get(message.structure.type_id).name.c_str(),
+            sizeof(buffer));
+      }
+      if (input_length > 0) {
+        LOG(WARNING, "%zu extra bytes on message of type %s\n", input_length,
+            type_cache::Get(message.structure.type_id).name.c_str());
+      }
+      fprintf(output, AOS_LOGGING_BASE_FORMAT "%.*s: %.*s\n", BASE_ARGS,
+              static_cast<int>(message.structure.string_length),
+              message.structure.serialized,
+              static_cast<int>(sizeof(buffer) - output_length), buffer);
+    } break;
+    case LogMessage::Type::kMatrix: {
+      char buffer[1024];
+      size_t output_length = sizeof(buffer);
+      if (message.message_length !=
+          static_cast<size_t>(message.matrix.rows * message.matrix.cols *
+                              MessageType::Sizeof(message.matrix.type))) {
+        LOG(FATAL, "expected %d bytes of matrix data but have %zu\n",
+            message.matrix.rows * message.matrix.cols *
+                MessageType::Sizeof(message.matrix.type),
+            message.message_length);
+      }
+      if (!PrintMatrix(buffer, &output_length,
+                       message.matrix.data + message.matrix.string_length,
+                       message.matrix.type, message.matrix.rows,
+                       message.matrix.cols)) {
+        LOG(FATAL, "printing %dx%d matrix of type %" PRIu32 " failed\n",
+            message.matrix.rows, message.matrix.cols, message.matrix.type);
+      }
+      fprintf(output, AOS_LOGGING_BASE_FORMAT "%.*s: %.*s\n", BASE_ARGS,
+              static_cast<int>(message.matrix.string_length),
+              message.matrix.data,
+              static_cast<int>(sizeof(buffer) - output_length), buffer);
+    } break;
+  }
+#undef BASE_ARGS
+}
+
+}  // namespace internal
+
+void SimpleLogImplementation::LogStruct(
+    log_level level, const ::std::string &message, size_t size,
+    const MessageType *type, const ::std::function<size_t(char *)> &serialize) {
+  char serialized[1024];
+  if (size > sizeof(serialized)) {
+    LOG(FATAL, "structure of type %s too big to serialize\n",
+        type->name.c_str());
+  }
+  size_t used = serialize(serialized);
+  char printed[1024];
+  size_t printed_bytes = sizeof(printed);
+  if (!PrintMessage(printed, &printed_bytes, serialized, &used, *type)) {
+    LOG(FATAL, "PrintMessage(%p, %p(=%zd), %p, %p(=%zd), %p(name=%s)) failed\n",
+        printed, &printed_bytes, printed_bytes, serialized, &used, used, type,
+        type->name.c_str());
+  }
+  DoLogVariadic(level, "%.*s: %.*s\n", static_cast<int>(message.size()),
+                message.data(),
+                static_cast<int>(sizeof(printed) - printed_bytes), printed);
+}
+
+void SimpleLogImplementation::LogMatrix(
+    log_level level, const ::std::string &message, uint32_t type_id,
+    int rows, int cols, const void *data) {
+  char serialized[1024];
+  if (static_cast<size_t>(rows * cols * MessageType::Sizeof(type_id)) >
+      sizeof(serialized)) {
+    LOG(FATAL, "matrix of size %u too big to serialize\n",
+        rows * cols * MessageType::Sizeof(type_id));
+  }
+  SerializeMatrix(type_id, serialized, data, rows, cols);
+  char printed[1024];
+  size_t printed_bytes = sizeof(printed);
+  if (!PrintMatrix(printed, &printed_bytes, serialized, type_id, rows, cols)) {
+    LOG(FATAL, "PrintMatrix(%p, %p(=%zd), %p, %" PRIu32 ", %d, %d) failed\n",
+        printed, &printed_bytes, printed_bytes, serialized, type_id, rows,
+        cols);
+  }
+  DoLogVariadic(level, "%.*s: %.*s\n", static_cast<int>(message.size()),
+                message.data(),
+                static_cast<int>(sizeof(printed) - printed_bytes), printed);
+}
+
+void HandleMessageLogImplementation::DoLog(log_level level, const char *format,
+                                           va_list ap) {
+  LogMessage message;
+  internal::FillInMessage(level, format, ap, &message);
+  HandleMessage(message);
+}
+
+void HandleMessageLogImplementation::LogStruct(
+    log_level level, const ::std::string &message_string, size_t size,
+    const MessageType *type, const ::std::function<size_t(char *)> &serialize) {
+  LogMessage message;
+  internal::FillInMessageStructure(level, message_string, size, type, serialize,
+                                   &message);
+  HandleMessage(message);
+}
+
+void HandleMessageLogImplementation::LogMatrix(
+    log_level level, const ::std::string &message_string, uint32_t type_id,
+    int rows, int cols, const void *data) {
+  LogMessage message;
+  internal::FillInMessageMatrix(level, message_string, type_id, rows, cols,
+                                data, &message);
+  HandleMessage(message);
+}
+
+StreamLogImplementation::StreamLogImplementation(FILE *stream)
+    : stream_(stream) {}
+
+void StreamLogImplementation::HandleMessage(const LogMessage &message) {
+  internal::PrintMessage(stream_, message);
+}
+
+void AddImplementation(LogImplementation *implementation) {
+  internal::Context *context = internal::Context::Get();
+
+  if (implementation->next() != NULL) {
+    LOG(FATAL, "%p already has a next implementation, but it's not"
+        " being used yet\n", implementation);
+  }
+
+  LogImplementation *old = context->implementation;
+  if (old != NULL) {
+    implementation->set_next(old);
+  }
+  SetGlobalImplementation(implementation);
+  root_implementation->have_other_implementation();
+}
+
+void Init() {
+  static Once<void> once(DoInit);
+  once.Get();
+}
+
+void Load() {
+  internal::Context::Get();
+}
+
+void Cleanup() {
+  internal::Context::Delete();
+}
+
+namespace {
+
+RawQueue *queue = NULL;
+
+int dropped_messages = 0;
+monotonic_clock::time_point dropped_start, backoff_start;
+// Wait this long after dropping a message before even trying to write any more.
+constexpr chrono::milliseconds kDropBackoff = chrono::milliseconds(100);
+
+LogMessage *GetMessageOrDie() {
+  LogMessage *message = static_cast<LogMessage *>(queue->GetMessage());
+  if (message == NULL) {
+    LOG(FATAL, "%p->GetMessage() failed\n", queue);
+  } else {
+    return message;
+  }
+}
+
+void Write(LogMessage *msg) {
+  if (__builtin_expect(dropped_messages > 0, false)) {
+    monotonic_clock::time_point message_time(
+        chrono::seconds(msg->seconds) + chrono::nanoseconds(msg->nseconds));
+    if (message_time - backoff_start < kDropBackoff) {
+      ++dropped_messages;
+      queue->FreeMessage(msg);
+      return;
+    }
+
+    LogMessage *dropped_message = GetMessageOrDie();
+    chrono::seconds dropped_start_sec = chrono::duration_cast<chrono::seconds>(
+        dropped_start.time_since_epoch());
+    chrono::nanoseconds dropped_start_nsec =
+        chrono::duration_cast<chrono::nanoseconds>(
+            dropped_start.time_since_epoch() - dropped_start_sec);
+    internal::FillInMessageVarargs(
+        ERROR, dropped_message,
+        "%d logs starting at %" PRId32 ".%" PRId32 " dropped\n",
+        dropped_messages, static_cast<int32_t>(dropped_start_sec.count()),
+        static_cast<int32_t>(dropped_start_nsec.count()));
+    if (queue->WriteMessage(dropped_message, RawQueue::kNonBlock)) {
+      dropped_messages = 0;
+    } else {
+      // Don't even bother trying to write this message because it's not likely
+      // to work and it would be confusing to have one log in the middle of a
+      // string of failures get through.
+      ++dropped_messages;
+      backoff_start = message_time;
+      queue->FreeMessage(msg);
+      return;
+    }
+  }
+  if (!queue->WriteMessage(msg, RawQueue::kNonBlock)) {
+    if (dropped_messages == 0) {
+      monotonic_clock::time_point message_time(
+          chrono::seconds(msg->seconds) + chrono::nanoseconds(msg->nseconds));
+      dropped_start = backoff_start = message_time;
+    }
+    ++dropped_messages;
+  }
+}
+
+class LinuxQueueLogImplementation : public LogImplementation {
+  __attribute__((format(GOOD_PRINTF_FORMAT_TYPE, 3, 0)))
+  void DoLog(log_level level, const char *format, va_list ap) override {
+    LogMessage *message = GetMessageOrDie();
+    internal::FillInMessage(level, format, ap, message);
+    Write(message);
+  }
+
+  void LogStruct(log_level level, const ::std::string &message_string,
+                 size_t size, const MessageType *type,
+                 const ::std::function<size_t(char *)> &serialize) override {
+    LogMessage *message = GetMessageOrDie();
+    internal::FillInMessageStructure(level, message_string, size, type,
+                                     serialize, message);
+    Write(message);
+  }
+
+  void LogMatrix(log_level level, const ::std::string &message_string,
+                 uint32_t type_id, int rows, int cols,
+                 const void *data) override {
+    LogMessage *message = GetMessageOrDie();
+    internal::FillInMessageMatrix(level, message_string, type_id, rows, cols,
+                                  data, message);
+    Write(message);
+  }
+};
+
+}  // namespace
+
+RawQueue *GetLoggingQueue() {
+  return RawQueue::Fetch("LoggingQueue", sizeof(LogMessage), 1323, 40000);
+}
+
+void RegisterQueueImplementation() {
+  Init();
+
+  queue = GetLoggingQueue();
+  if (queue == NULL) {
+    Die("logging: couldn't fetch queue\n");
+  }
+
+  AddImplementation(new LinuxQueueLogImplementation());
+}
+
+}  // namespace logging
+}  // namespace aos