diff --git a/demos/STM32/RT-STM32G474RE-NUCLEO64-SB_HOST_DYNAMIC/cfg/sbconf.h b/demos/STM32/RT-STM32G474RE-NUCLEO64-SB_HOST_DYNAMIC/cfg/sbconf.h
index cfd1a98f5..89c1e8c10 100644
--- a/demos/STM32/RT-STM32G474RE-NUCLEO64-SB_HOST_DYNAMIC/cfg/sbconf.h
+++ b/demos/STM32/RT-STM32G474RE-NUCLEO64-SB_HOST_DYNAMIC/cfg/sbconf.h
@@ -38,6 +38,13 @@
 #define SB_CFG_NUM_REGIONS                  2
 #endif
 
+/**
+ * @brief   Enables support for sandbox Virtual IRQs.
+ */
+#if !defined(SB_CFG_ENABLE_VRQ) || defined(__DOXYGEN__)
+#define SB_CFG_ENABLE_VRQ                   TRUE
+#endif
+
 /**
  * @brief   Enables Posix API in sandboxes using VFS.
  */
diff --git a/demos/STM32/RT-STM32G474RE-NUCLEO64-SB_HOST_STATIC/cfg/sbconf.h b/demos/STM32/RT-STM32G474RE-NUCLEO64-SB_HOST_STATIC/cfg/sbconf.h
index cfd1a98f5..89c1e8c10 100644
--- a/demos/STM32/RT-STM32G474RE-NUCLEO64-SB_HOST_STATIC/cfg/sbconf.h
+++ b/demos/STM32/RT-STM32G474RE-NUCLEO64-SB_HOST_STATIC/cfg/sbconf.h
@@ -38,6 +38,13 @@
 #define SB_CFG_NUM_REGIONS                  2
 #endif
 
+/**
+ * @brief   Enables support for sandbox Virtual IRQs.
+ */
+#if !defined(SB_CFG_ENABLE_VRQ) || defined(__DOXYGEN__)
+#define SB_CFG_ENABLE_VRQ                   TRUE
+#endif
+
 /**
  * @brief   Enables Posix API in sandboxes using VFS.
  */
diff --git a/demos/STM32/RT-STM32L4R9-DISCOVERY-RAM_SB_HOST_DYNAMIC/cfg/sbconf.h b/demos/STM32/RT-STM32L4R9-DISCOVERY-RAM_SB_HOST_DYNAMIC/cfg/sbconf.h
index cfd1a98f5..89c1e8c10 100644
--- a/demos/STM32/RT-STM32L4R9-DISCOVERY-RAM_SB_HOST_DYNAMIC/cfg/sbconf.h
+++ b/demos/STM32/RT-STM32L4R9-DISCOVERY-RAM_SB_HOST_DYNAMIC/cfg/sbconf.h
@@ -38,6 +38,13 @@
 #define SB_CFG_NUM_REGIONS                  2
 #endif
 
+/**
+ * @brief   Enables support for sandbox Virtual IRQs.
+ */
+#if !defined(SB_CFG_ENABLE_VRQ) || defined(__DOXYGEN__)
+#define SB_CFG_ENABLE_VRQ                   TRUE
+#endif
+
 /**
  * @brief   Enables Posix API in sandboxes using VFS.
  */
diff --git a/demos/STM32/RT-STM32L4R9-DISCOVERY-SB_HOST_STATIC/cfg/sbconf.h b/demos/STM32/RT-STM32L4R9-DISCOVERY-SB_HOST_STATIC/cfg/sbconf.h
index cfd1a98f5..89c1e8c10 100644
--- a/demos/STM32/RT-STM32L4R9-DISCOVERY-SB_HOST_STATIC/cfg/sbconf.h
+++ b/demos/STM32/RT-STM32L4R9-DISCOVERY-SB_HOST_STATIC/cfg/sbconf.h
@@ -38,6 +38,13 @@
 #define SB_CFG_NUM_REGIONS                  2
 #endif
 
+/**
+ * @brief   Enables support for sandbox Virtual IRQs.
+ */
+#if !defined(SB_CFG_ENABLE_VRQ) || defined(__DOXYGEN__)
+#define SB_CFG_ENABLE_VRQ                   TRUE
+#endif
+
 /**
  * @brief   Enables Posix API in sandboxes using VFS.
  */
diff --git a/os/sb/host/compilers/GCC/sbhost.mk b/os/sb/host/compilers/GCC/sbhost.mk
index 221b98bde..052fb8997 100644
--- a/os/sb/host/compilers/GCC/sbhost.mk
+++ b/os/sb/host/compilers/GCC/sbhost.mk
@@ -1,6 +1,7 @@
 # List of the ChibiOS ARMv7-M sandbox host files.
 SBHOSTSRC = $(CHIBIOS)/os/sb/host/sbhost.c \
 			$(CHIBIOS)/os/sb/host/sbapi.c \
+			$(CHIBIOS)/os/sb/host/sbvrq.c \
 			$(CHIBIOS)/os/sb/host/sbelf.c \
 			$(CHIBIOS)/os/sb/host/sbposix.c
           
diff --git a/os/sb/host/sb.h b/os/sb/host/sb.h
index 7e5abd47b..67634b3cf 100644
--- a/os/sb/host/sb.h
+++ b/os/sb/host/sb.h
@@ -94,6 +94,10 @@
 #error "SB_CFG_NUM_REGIONS not defined in sbconf.h"
 #endif
 
+#if !defined(SB_CFG_ENABLE_VRQ) || defined(__DOXYGEN__)
+#error "SB_CFG_ENABLE_VRQ not defined in sbconf.h"
+#endif
+
 #if !defined(SB_CFG_ENABLE_VFS) || defined(__DOXYGEN__)
 #error "SB_CFG_ENABLE_VFS not defined in sbconf.h"
 #endif
@@ -281,6 +285,7 @@ extern "C" {
 /*===========================================================================*/
 
 #include "sbsysc.h"
+#include "sbvrq.h"
 #include "sbelf.h"
 #include "sbposix.h"
 #include "sbapi.h"
diff --git a/os/sb/host/sbapi.c b/os/sb/host/sbapi.c
index a8a73e308..899579af6 100644
--- a/os/sb/host/sbapi.c
+++ b/os/sb/host/sbapi.c
@@ -36,6 +36,20 @@
 /* Module local definitions.                                                 */
 /*===========================================================================*/
 
+static void sb_api_stdio(struct port_extctx *ectxp);
+static void sb_api_exit(struct port_extctx *ctxp);
+static void sb_api_get_systime(struct port_extctx *ctxp);
+static void sb_api_get_frequency(struct port_extctx *ctxp);
+static void sb_api_sleep(struct port_extctx *ctxp);
+static void sb_api_sleep_until_windowed(struct port_extctx *ctxp);
+static void sb_api_wait_message(struct port_extctx *ctxp);
+static void sb_api_reply_message(struct port_extctx *ctxp);
+static void sb_api_wait_one_timeout(struct port_extctx *ctxp);
+static void sb_api_wait_any_timeout(struct port_extctx *ctxp);
+static void sb_api_wait_all_timeout(struct port_extctx *ctxp);
+static void sb_api_broadcast_flags(struct port_extctx *ctxp);
+static void sb_api_loadelf(struct port_extctx *ectxp);
+
 /**
  * @name    Standard API handlers
  * @{
@@ -960,26 +974,8 @@ static void sb_cleanup(void) {
 #endif
 }
 
-/*===========================================================================*/
-/* Module exported functions.                                                */
-/*===========================================================================*/
-
-void __sb_abort(msg_t msg) {
-
-  chSysUnlock();
-
-  sb_cleanup();
-
-  chSysLock();
-#if CH_CFG_USE_EVENTS == TRUE
-  chEvtBroadcastI(&sb.termination_es);
-#endif
-  chThdExitS(msg);
-  chSysHalt("zombies");
-}
-
 #if (SB_CFG_ENABLE_VFS == TRUE) || defined(__DOXYGEN__)
-void sb_api_stdio(struct port_extctx *ectxp) {
+static void sb_api_stdio(struct port_extctx *ectxp) {
 
   switch (ectxp->r0) {
   case SB_POSIX_OPEN:
@@ -1052,7 +1048,7 @@ void sb_api_stdio(struct port_extctx *ectxp) {
 }
 #endif /* SB_CFG_ENABLE_VFS == TRUE */
 
-void sb_api_exit(struct port_extctx *ectxp) {
+static void sb_api_exit(struct port_extctx *ectxp) {
 
   sb_cleanup();
 
@@ -1067,17 +1063,17 @@ void sb_api_exit(struct port_extctx *ectxp) {
   ectxp->r0 = CH_RET_ENOSYS;
 }
 
-void sb_api_get_systime(struct port_extctx *ectxp) {
+static void sb_api_get_systime(struct port_extctx *ectxp) {
 
   ectxp->r0 = (uint32_t)chVTGetSystemTimeX();
 }
 
-void sb_api_get_frequency(struct port_extctx *ectxp) {
+static void sb_api_get_frequency(struct port_extctx *ectxp) {
 
   ectxp->r0 = (uint32_t)CH_CFG_ST_FREQUENCY;
 }
 
-void sb_api_sleep(struct port_extctx *ectxp) {
+static void sb_api_sleep(struct port_extctx *ectxp) {
   sysinterval_t interval = (sysinterval_t )ectxp->r0;
 
   if (interval != TIME_IMMEDIATE) {
@@ -1087,14 +1083,14 @@ void sb_api_sleep(struct port_extctx *ectxp) {
   ectxp->r0 = CH_RET_SUCCESS;
 }
 
-void sb_api_sleep_until_windowed(struct port_extctx *ectxp) {
+static void sb_api_sleep_until_windowed(struct port_extctx *ectxp) {
 
   chThdSleepUntilWindowed((systime_t )ectxp->r0, (systime_t )ectxp->r1);
 
   ectxp->r0 = CH_RET_SUCCESS;
 }
 
-void sb_api_wait_message(struct port_extctx *ectxp) {
+static void sb_api_wait_message(struct port_extctx *ectxp) {
 #if CH_CFG_USE_MESSAGES == TRUE
   sb_class_t *sbp = (sb_class_t *)chThdGetSelfX()->ctx.syscall.p;
 
@@ -1117,7 +1113,7 @@ void sb_api_wait_message(struct port_extctx *ectxp) {
 #endif
 }
 
-void sb_api_reply_message(struct port_extctx *ectxp) {
+static void sb_api_reply_message(struct port_extctx *ectxp) {
 #if CH_CFG_USE_MESSAGES == TRUE
   sb_class_t *sbp = (sb_class_t *)chThdGetSelfX()->ctx.syscall.p;
 
@@ -1139,7 +1135,7 @@ void sb_api_reply_message(struct port_extctx *ectxp) {
 #endif
 }
 
-void sb_api_wait_one_timeout(struct port_extctx *ectxp) {
+static void sb_api_wait_one_timeout(struct port_extctx *ectxp) {
 #if CH_CFG_USE_EVENTS == TRUE
 
   ectxp->r0 = (uint32_t)chEvtWaitOneTimeout((eventmask_t )ectxp->r0,
@@ -1149,7 +1145,7 @@ void sb_api_wait_one_timeout(struct port_extctx *ectxp) {
 #endif
 }
 
-void sb_api_wait_any_timeout(struct port_extctx *ectxp) {
+static void sb_api_wait_any_timeout(struct port_extctx *ectxp) {
 #if CH_CFG_USE_EVENTS == TRUE
 
   ectxp->r0 = (uint32_t)chEvtWaitAnyTimeout((eventmask_t )ectxp->r0,
@@ -1159,7 +1155,7 @@ void sb_api_wait_any_timeout(struct port_extctx *ectxp) {
 #endif
 }
 
-void sb_api_wait_all_timeout(struct port_extctx *ectxp) {
+static void sb_api_wait_all_timeout(struct port_extctx *ectxp) {
 #if CH_CFG_USE_EVENTS == TRUE
 
   ectxp->r0 = (uint32_t)chEvtWaitAllTimeout((eventmask_t )ectxp->r0,
@@ -1169,7 +1165,7 @@ void sb_api_wait_all_timeout(struct port_extctx *ectxp) {
 #endif
 }
 
-void sb_api_broadcast_flags(struct port_extctx *ectxp) {
+static void sb_api_broadcast_flags(struct port_extctx *ectxp) {
 #if CH_CFG_USE_EVENTS == TRUE
   sb_class_t *sbp = (sb_class_t *)chThdGetSelfX()->ctx.syscall.p;
 
@@ -1180,7 +1176,7 @@ void sb_api_broadcast_flags(struct port_extctx *ectxp) {
 #endif
 }
 
-void sb_api_loadelf(struct port_extctx *ectxp) {
+static void sb_api_loadelf(struct port_extctx *ectxp) {
 #if (SB_CFG_ENABLE_VFS == TRUE) || defined(__DOXYGEN__)
   sb_class_t *sbp = (sb_class_t *)chThdGetSelfX()->ctx.syscall.p;
   const char *fname = (const char *)ectxp->r0;
@@ -1202,4 +1198,22 @@ void sb_api_loadelf(struct port_extctx *ectxp) {
 #endif
 }
 
+/*===========================================================================*/
+/* Module exported functions.                                                */
+/*===========================================================================*/
+
+void __sb_abort(msg_t msg) {
+
+  chSysUnlock();
+
+  sb_cleanup();
+
+  chSysLock();
+#if CH_CFG_USE_EVENTS == TRUE
+  chEvtBroadcastI(&sb.termination_es);
+#endif
+  chThdExitS(msg);
+  chSysHalt("zombies");
+}
+
 /** @} */
diff --git a/os/sb/host/sbapi.h b/os/sb/host/sbapi.h
index 5ac6cfac0..0939208fb 100644
--- a/os/sb/host/sbapi.h
+++ b/os/sb/host/sbapi.h
@@ -49,48 +49,6 @@
  */
 typedef void (*port_syscall_t)(struct port_extctx *ectx);
 
-/**
- * @brief   Sandbox Stream interface methods.
- * @note    Is intentionally compatible with HAL streams but we have to
- *          duplicate is because we don't want dependencies with HAL in
- *          this subsystem.
- */
-struct SandboxStreamVMT {
-  /**
-   * @brief   Object instance offset.
-   */
-  size_t instance_offset;
-  /**
-   * @brief   Stream write buffer method.
-   */
-  size_t (*write)(void *instance, const uint8_t *bp, size_t n);
-  /**
-   * @brief   Stream read buffer method.
-   */
-  size_t (*read)(void *instance, uint8_t *bp, size_t n);
-  /**
-   * @brief   Channel put method, blocking.
-   */
-  msg_t (*put)(void *instance, uint8_t b);
-  /**
-   * @brief   Channel get method, blocking.
-   */
-  msg_t (*get)(void *instance);
-};
-
-/**
- * @brief   Sandbox Stream class.
- * @note    Is intentionally compatible with HAL streams but we have to
- *          duplicate is because we don't want dependencies with HAL in
- *          this subsystem.
- */
-typedef struct {
-  /**
-   * @brief Virtual Methods Table.
-   */
-  const struct SandboxStreamVMT *vmt;
-} SandboxStream;
-
 /*===========================================================================*/
 /* Module macros.                                                            */
 /*===========================================================================*/
@@ -102,19 +60,7 @@ typedef struct {
 #ifdef __cplusplus
 extern "C" {
 #endif
-  void sb_api_stdio(struct port_extctx *ectxp);
-  void sb_api_exit(struct port_extctx *ctxp);
-  void sb_api_get_systime(struct port_extctx *ctxp);
-  void sb_api_get_frequency(struct port_extctx *ctxp);
-  void sb_api_sleep(struct port_extctx *ctxp);
-  void sb_api_sleep_until_windowed(struct port_extctx *ctxp);
-  void sb_api_wait_message(struct port_extctx *ctxp);
-  void sb_api_reply_message(struct port_extctx *ctxp);
-  void sb_api_wait_one_timeout(struct port_extctx *ctxp);
-  void sb_api_wait_any_timeout(struct port_extctx *ctxp);
-  void sb_api_wait_all_timeout(struct port_extctx *ctxp);
-  void sb_api_broadcast_flags(struct port_extctx *ctxp);
-  void sb_api_loadelf(struct port_extctx *ectxp);
+
 #ifdef __cplusplus
 }
 #endif
diff --git a/os/sb/host/sbvrq.c b/os/sb/host/sbvrq.c
new file mode 100644
index 000000000..ec1644a0c
--- /dev/null
+++ b/os/sb/host/sbvrq.c
@@ -0,0 +1,58 @@
+/*
+    ChibiOS - Copyright (C) 2006,2007,2008,2009,2010,2011,2012,2013,2014,
+              2015,2016,2017,2018,2019,2020,2021 Giovanni Di Sirio.
+
+    This file is part of ChibiOS.
+
+    ChibiOS 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 version 3 of the License.
+
+    ChibiOS 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 this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+/**
+ * @file    sb/host/sbvrq.c
+ * @brief   ARM SandBox host Virtual IRQs code.
+ *
+ * @addtogroup ARM_SANDBOX_VRQ
+ * @{
+ */
+
+#include "sb.h"
+
+#if (SB_CFG_ENABLE_VRQ == TRUE) || defined(__DOXYGEN__)
+
+/*===========================================================================*/
+/* Module local definitions.                                                 */
+/*===========================================================================*/
+
+/*===========================================================================*/
+/* Module exported variables.                                                */
+/*===========================================================================*/
+
+/*===========================================================================*/
+/* Module local types.                                                       */
+/*===========================================================================*/
+
+/*===========================================================================*/
+/* Module local variables.                                                   */
+/*===========================================================================*/
+
+/*===========================================================================*/
+/* Module local functions.                                                   */
+/*===========================================================================*/
+
+/*===========================================================================*/
+/* Module exported functions.                                                */
+/*===========================================================================*/
+
+#endif /* SB_CFG_ENABLE_VRQ == TRUE */
+
+/** @} */
diff --git a/os/sb/host/sbvrq.h b/os/sb/host/sbvrq.h
new file mode 100644
index 000000000..83077a765
--- /dev/null
+++ b/os/sb/host/sbvrq.h
@@ -0,0 +1,78 @@
+/*
+    ChibiOS - Copyright (C) 2006,2007,2008,2009,2010,2011,2012,2013,2014,
+              2015,2016,2017,2018,2019,2020,2021 Giovanni Di Sirio.
+
+    This file is part of ChibiOS.
+
+    ChibiOS 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 version 3 of the License.
+
+    ChibiOS 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 this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+/**
+ * @file    sb/host/sbvrq.h
+ * @brief   ARM SandBox host Virtual IRQs macros and structures.
+ *
+ * @addtogroup ARM_SANDBOX_HOSTAPI
+ * @{
+ */
+
+#ifndef SBVRQ_H
+#define SBVRQ_H
+
+#if (SB_CFG_ENABLE_VRQ == TRUE) || defined(__DOXYGEN__)
+
+/*===========================================================================*/
+/* Module constants.                                                         */
+/*===========================================================================*/
+
+/*===========================================================================*/
+/* Module pre-compile time settings.                                         */
+/*===========================================================================*/
+
+/*===========================================================================*/
+/* Derived constants and error checks.                                       */
+/*===========================================================================*/
+
+/*===========================================================================*/
+/* Module data structures and types.                                         */
+/*===========================================================================*/
+
+/**
+ * @brief   Type of a mask of Virtual IRQs.
+ */
+typedef uint32_t sb_vrqmask_t;
+
+/*===========================================================================*/
+/* Module macros.                                                            */
+/*===========================================================================*/
+
+/*===========================================================================*/
+/* External declarations.                                                    */
+/*===========================================================================*/
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+  void sbVRQPendI(sb_class_t *sbp, sb_vrqmask_t vmask);
+#ifdef __cplusplus
+}
+#endif
+
+/*===========================================================================*/
+/* Module inline functions.                                                  */
+/*===========================================================================*/
+
+#endif /* SB_CFG_ENABLE_VRQ == TRUE */
+
+#endif /* SBVRQ_H */
+
+/** @} */