diff --git a/util/build-gcc.sh b/util/build-gcc.sh
index 96fc266c..e8253796 100644
--- a/util/build-gcc.sh
+++ b/util/build-gcc.sh
@@ -1,6 +1,8 @@
 #!/bin/bash
 DIR="$( cd "$( dirname "${BASH_SOURCE[0]}" )" && pwd )"
 
+$DIR/check-reqs.sh
+
 TARGET=i686-pc-toaru
 PREFIX="$DIR/local"
 TOARU_SYSROOT="$DIR/../base"
diff --git a/util/check-reqs.sh b/util/check-reqs.sh
new file mode 100755
index 00000000..3d9e750e
--- /dev/null
+++ b/util/check-reqs.sh
@@ -0,0 +1,79 @@
+#!/bin/bash
+
+RET=0
+
+if ! which python3.6 >/dev/null; then
+    echo "python3.6 is required to run build tools (and eventually cross-compile python3.6)"
+    RET=1
+fi
+
+if ! which genext2fs >/dev/null; then
+    echo "genext2fs is needed to build ramdisk images"
+    RET=1
+else
+    if [ -z "$(genext2fs --help 2>&1 | grep -- "block-size")" ]; then
+        echo "genext2fs must support the -B (--block-size) argument; try building with Debian patches"
+        RET=1
+    fi
+fi
+
+if ! which mcopy >/dev/null; then
+    echo "mtools is required to build FAT images for EFI / hybrid ISOs"
+    RET=1
+fi
+
+if ! which xorriso >/dev/null; then
+    echo "xorriso is required to build ISO CD images"
+    RET=1
+fi
+
+if ! which yasm >/dev/null; then
+    echo "yasm is required to build some assembly sources"
+    RET=1
+fi
+
+if ! which autoconf >/dev/null; then
+    echo "autoconf is required to build GCC cross-compiler"
+    RET=1
+fi
+
+if ! which automake >/dev/null; then
+    echo "automake is required to build GCC cross-compiler"
+    RET=1
+fi
+
+if ! which wget >/dev/null; then
+    echo "wget is required to build GCC cross-compiler"
+    RET=1
+fi
+
+if [ ! -e /usr/lib32/crt0-efi-ia32.o ]; then
+    echo "gnu-efi is required to build EFI loaders"
+    RET=1
+fi
+
+if ! cpp <(echo "#include \"gmp.h\"") >/dev/null 2>/dev/null; then
+    echo "GMP headers are required to build GCC cross-compiler"
+    RET=1
+fi
+
+if ! cpp <(echo "#include \"mpfr.h\"") >/dev/null 2>/dev/null; then
+    echo "MPFR headers are required to build GCC cross-compiler"
+    RET=1
+fi
+
+if ! cpp <(echo "#include \"mpfr.h\"") >/dev/null 2>/dev/null; then
+    echo "MPFR headers are required to build GCC cross-compiler"
+    RET=1
+fi
+
+if ! cpp <(echo "#include \"mpc.h\"") >/dev/null 2>/dev/null; then
+    echo "MPC headers are required to build GCC cross-compiler"
+    RET=1
+fi
+
+echo "butts"
+RET=1
+
+exit $RET
+
diff --git a/util/prompt.sh b/util/prompt.sh
index c80921f2..04143f21 100755
--- a/util/prompt.sh
+++ b/util/prompt.sh
@@ -2,6 +2,12 @@
 
 DIR="$( cd "$( dirname "${BASH_SOURCE[0]}" )" && pwd )"
 
+if ! $DIR/check-reqs.sh; then
+    echo "A toolchain is not available and the above issues were found." >&2
+    echo "Resolve the problems above and run \`make\` again." >&2
+    echo -n "n" && exit 1
+fi
+
 echo -n "Toolchain has not been built. Would you like to build it now? (y/n) " >&2
 read response
 case $response in