diff --git a/BUILD b/BUILD
index 9c8b007..0124b2d 100644
--- a/BUILD
+++ b/BUILD
@@ -2,7 +2,6 @@
     name = "nos_headers",
     hdrs = [
         "nugget/include/app_nugget.h",
-        "nugget/include/app_transport_test.h",
         "nugget/include/application.h",
         "nugget/include/avb.h",
         "nugget/include/flash_layout.h",
diff --git a/nugget/include/app_transport_test.h b/nugget/include/app_transport_test.h
deleted file mode 100644
index 0c0b4ba..0000000
--- a/nugget/include/app_transport_test.h
+++ /dev/null
@@ -1,25 +0,0 @@
-/*
- * Copyright (C) 2018 The Android Open Source Project
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *      http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-#ifndef __CROS_EC_INCLUDE_APP_TRANSPORT_TEST_H
-#define __CROS_EC_INCLUDE_APP_TRANSPORT_TEST_H
-
-/* App commands */
-#define TRANSPORT_TEST_NOP  5    /* Does nothing successfully */
-#define TRANSPORT_TEST_1234 8    /* Returns 0x01020304 successfully */
-#define TRANSPORT_TEST_9876 9    /* Only successful if the arg is 0x09080706 */
-#define TRANSPORT_TEST_HANG 12   /* Forgets to call app_reply() */
-
-#endif /* __CROS_EC_INCLUDE_APP_TRANSPORT_TEST_H */
diff --git a/nugget/include/application.h b/nugget/include/application.h
index dfc9b2b..45824b3 100644
--- a/nugget/include/application.h
+++ b/nugget/include/application.h
@@ -75,7 +75,6 @@
 
 /* Fake apps used only for testing */
 #define APP_ID_AVB_TEST          0x11
-#define APP_ID_TRANSPORT_TEST    0x12
 
 /* This app ID should only be used by tests. */
 #define APP_ID_TEST              0xff
@@ -200,69 +199,20 @@
  * then performs the requested operation and transititions to a "done" state.
  * The Master will retrieve the application status and any reply data from
  * Nugget OS, after which the application is ready to handle the next command.
- */
-
-#define TRANSPORT_V0    0x0000
-#define TRANSPORT_V1    0x0001
-
-/* Command information for the transport protocol. */
-struct transport_command_info {
-  /* v1 fields */
-  uint16_t version;          /* max version used by master */
-  uint16_t crc;              /* CRC of some command fields */
-  uint16_t reply_len_hint;   /* max that the master will read */
-} __packed;
-
-#define COMMAND_INFO_MAX_LENGTH 32
-/* If more data needs to be sent, chain a new struct to the end of this one. It
- * will require its own CRC for data integrity and something to signify the
- * presence of the extra data. */
-
-struct transport_status {
-  /* v0 fields */
-  uint32_t status;         /* status of the app */
-  uint16_t reply_len;      /* length of available response data */
-  /* v1 fields */
-  uint16_t length;         /* length of this message, max 255 */
-  uint16_t version;        /* max version used by slave */
-  uint16_t flags;          /* space for more protocol state flags */
-  uint16_t crc;            /* CRC of this status with crc set to 0 */
-  uint16_t reply_crc;      /* CRC of the reply data */
-} __packed;
-
-/* Valid range of lengths for the status message */
-#define STATUS_MIN_LENGTH 0x10
-#define STATUS_MAX_LENGTH 0xff
-
-/* Flags used in the status message */
-#define STATUS_FLAG_WORKING 0x0001 /* added in v1 */
-
-/* Pre-calculated CRCs for different status responses set by in the interrupt
- * context where the CRC would otherwise not be calculated. */
-#define STATUS_CRC_FOR_IDLE              0x54c1
-#define STATUS_CRC_FOR_WORKING           0x2101
-#define STATUS_CRC_FOR_ERROR_TOO_MUCH    0x97c0
-
-/*
+ *
  * Applications that wish to use this transport API will need to declare a
  * private struct app_transport which Nugget OS can use to maintain the state:
  */
+
 struct app_transport {
-  void (*done_fn)(struct app_transport *);    /* optional cleanup function */
-  /* Note: Any done_fn() is called in interrupt context. Be quick. */
+  uint32_t command;                           /* from master */
+  volatile uint32_t status;                   /* current application status */
   uint8_t *request, *response;                /* input/output data buffer */
   uint16_t max_request_len, max_response_len; /* data buffer sizes */
-  /* The following are used for the incoming command. */
-  uint32_t command;                           /* from master */
-  uint32_t command_info_len;
-  union {
-    struct transport_command_info info;
-    uint8_t data[COMMAND_INFO_MAX_LENGTH];    /* space for future growth */
-  } command_info;                             /* extra info about the command */
-  uint16_t request_len;                       /* command data buffer size */
-  uint16_t response_idx;                      /* current index into response */
-  struct transport_status status[2];          /* current transport_status */
-  volatile uint8_t status_idx;                /* index of active status */
+  uint16_t request_len, response_len;         /* current buffer count */
+  uint16_t request_idx, response_idx;         /* used internally */
+  void (*done_fn)(struct app_transport *);    /* optional cleanup function */
+  /* Note: Any done_fn() is called in interrupt context. Be quick. */
 };
 
 /*
@@ -274,24 +224,18 @@
  */
 #define __TRANSPORT_ALIGNED__ __attribute__((aligned(8)))
 
+/* For debugging if needed */
+extern void dump_transport_state(const struct app_transport *s);
+
 /*
  * The application will need to provide a write_to_app_fn_t function that will
  * be invoked when a new request is ready to be processed. All command and data
  * parameters will already be present in the app's struct app_transport, so it
  * just needs to awaken the application task to do the work.
  *
- * When awakened, the application task must check that there were no errors in
- * the transmission of the request by calling this function. If it returns
- * true, the task should go back to sleep until the next request arrives.
- */
-int request_is_invalid(struct app_transport *s);
-/*
  * When processing is finished, the app should call the app_reply() function to
- * return its status code and specify the length of any data it has placed into
- * the response buffer, and then it can go back to sleep until its next
- * invocation. CAUTION: The Master polls for app completion independently, so
- * it may immediately begin retrieving the results as soon as this function
- * is called *without* waiting for the Nugget OS app to go to sleep.
+ * return its status code and specify length of any data it has placed into the
+ * response buffer, and then it can go back to sleep until its next invocation.
  */
 void app_reply(struct app_transport *st, uint32_t status, uint16_t reply_len);
 
@@ -304,7 +248,6 @@
   APP_ERROR_TOO_MUCH,        /* caller sent too much data */
   APP_ERROR_IO,              /* problem sending or receiving data */
   APP_ERROR_RPC,             /* problem during RPC communication */
-  APP_ERROR_CHECKSUM,        /* checksum failed, only used within protocol */
   /* more? */
 
   APP_SPECIFIC_ERROR = 0x20, /* "should be enough for anybody" */
@@ -371,7 +314,6 @@
 
 /* Command flags used internally by Transport API messages */
 #define CMD_TRANSPORT       0x40000000    /* 1=Transport API message */
-/* When CMD_TRANSPORT is set, the following bits have meaning */
 #define CMD_IS_DATA         0x20000000    /* 1=data msg 0=status msg */
 #define CMD_MORE_TO_COME    0x10000000    /* 1=continued 0=new */