diff --git a/build.sh b/build.sh
index ebbcdfe1a..8cba67850 100755
--- a/build.sh
+++ b/build.sh
@@ -12,10 +12,12 @@ usage()
 {
     echo "build.sh:      Invoke make for a particular architecture and configuration."
     echo "Usage:"
-    echo "./build.sh [-X | -A | -6 | -a ARCH] [-c CONFIG] [-f FILESYSTEM_CONFIG] TARGET..."
+    echo "./build.sh [-X | -A | -5 | -R | -a ARCH] [-c CONFIG] [-f FILESYSTEM_CONFIG] TARGET..."
     echo "    -X         Equivalent to -a x86_64."
     echo "    -A         Equivalent to -a aarch64."
-    echo "    -6         Equivalent to -a i686."
+    echo "    -5         Equivalent to -a i586."
+    echo "    -6         Equivalent to -a i586 (deprecated, use -5 instead)."
+    echo "    -R         Equivalent to -a riscv64gc."
     echo "    -a ARCH:   Processor Architecture. Normally one of x86_64, aarch64 or"
     echo "               i686. ARCH is not checked, so you can add a new architecture."
     echo "               Defaults to the directory containing the FILESYSTEM_CONFIG file,"
@@ -61,7 +63,9 @@ do
         f) FILESYSTEM_CONFIG="$OPTARG";;
         X) ARCH="x86_64";;
         A) ARCH="aarch64";;
-        6) ARCH="i686";;
+        R) ARCH="riscv64gc";;
+        5) ARCH="i586";;
+        6) ARCH="i586";;
         h) usage;;
         \?) echo "Unknown option -$OPTARG, try -h for help"; exit;;
         :) echo "-$OPTARG requires a value"; exit;;
@@ -75,8 +79,9 @@ if [ -z "$ARCH" ] && [ -n "$FILESYSTEM_CONFIG" ]; then
     case "$ARCH" in
         x86_64) : ;;
         aarch64) : ;;
-        i686) : ;;
-        \?) ARCH=""; echo "Unknown Architecture, please specify x86_64, aarch64 or i686";;
+        riscv64gc) : ;;
+        i586) : ;;
+        \?) ARCH=""; echo "Unknown Architecture, please specify x86_64, aarch64, risc64gc or i586";;
     esac
 fi
 
diff --git a/mk/config.mk b/mk/config.mk
index cfba16aae..9ac7c0eb4 100644
--- a/mk/config.mk
+++ b/mk/config.mk
@@ -5,7 +5,7 @@
 HOST_ARCH?=$(shell uname -m)
 
 # Configuration
-## Architecture to build Redox for (aarch64, i686, or x86_64). Defaults to a host one
+## Architecture to build Redox for (aarch64, i586, or x86_64). Defaults to a host one
 ARCH?=$(HOST_ARCH)
 ## Sub-device type for aarch64 if needed
 BOARD?=
@@ -125,9 +125,9 @@ ifeq ($(ARCH),riscv64gc)
 	export TARGET=riscv64gc-unknown-redox
 	export GNU_TARGET=riscv64-unknown-redox
 else ifeq ($(ARCH),i686)
-# FIXME change TARGET to i586 before the next prefix rebuild
-	export TARGET=i686-unknown-redox
-	export GNU_TARGET=i686-unknown-redox
+	ARCH=i586
+	export TARGET=i586-unknown-redox
+	export GNU_TARGET=i586-unknown-redox
 else
 	export TARGET=$(ARCH)-unknown-redox
 	export GNU_TARGET=$(ARCH)-unknown-redox
diff --git a/mk/qemu.mk b/mk/qemu.mk
index 688526a9e..6d1ff6226 100644
--- a/mk/qemu.mk
+++ b/mk/qemu.mk
@@ -5,7 +5,7 @@ QEMUFLAGS=-d guest_errors -name "Redox OS $(ARCH)"
 netboot?=no
 VGA_SUPPORTED=no
 
-ifeq ($(ARCH),i686)
+ifeq ($(ARCH),i586)
 	audio?=ac97
 	gpu?=vga
 	uefi=no
@@ -16,7 +16,7 @@ ifeq ($(ARCH),i686)
 	QEMU_SMP?=1
 	QEMU_MEM?=1024
 
-	# Default to using kvm when arch is i686 and host is x86_64
+	# Default to using kvm when arch is i586 and host is x86_64
 	ifeq ($(HOST_ARCH),x86_64)
 		kvm?=yes
 	endif