diff --git a/.circleci/config.yml b/.circleci/config.yml
index c7be4c01c..a789a7a41 100644
--- a/.circleci/config.yml
+++ b/.circleci/config.yml
@@ -17,6 +17,30 @@ version: 2
     - store_test_results: # Note that this command will fail when running CircleCI locally, that is expected behaviour
         path: test-results
 
+.emulatedjob: &emulatedjob
+  machine:
+    image: ubuntu-1604:201903-01
+  steps:
+    - checkout
+    - run:
+        name: Install the emulation handlers
+        command: docker run --rm --privileged multiarch/qemu-user-static:register --reset
+    - run: # Skipping sig-sphincs because it exhausts memory on CircleCI
+        name: Run the tests in a container
+        command: |
+          docker run -e SKIP_TESTS=style --rm -v `pwd`:`pwd` -w `pwd` dstebila/liboqs:debian-buster-${ARCH}-0.1.0 /bin/bash -c "
+          uname -a &&
+          file /bin/ls &&
+          autoreconf -i &&
+          ./configure --enable-silent-rules ${CONFIGURE_ARGS} &&
+          make -j &&
+          make check &&
+          mkdir -p test-results/pytest &&
+          python3 -m pytest --verbose --junitxml=test-results/pytest/results.xml --numprocesses=auto
+          "
+    - store_test_results:
+        path: test-results
+
 jobs:
   debian-buster-amd64:
     <<: *oqsjob
@@ -24,6 +48,21 @@ jobs:
       IMAGE: dstebila/liboqs:debian-buster-amd64-0.1.0
       CONFIGURE_ARGS: --disable-kem-bike # FIXME: BIKE doesn't work on CircleCI due to symbol _CMP_LT_OS not being defined
       SKIP_TESTS: style
+  debian-buster-aarch64:
+    <<: *emulatedjob
+    environment:
+      ARCH: aarch64
+      CONFIGURE_ARGS: --disable-sig-sphincs # sig-sphincs exhausts memory on CircleCI servers
+  debian-buster-armhf:
+    <<: *emulatedjob
+    environment:
+      ARCH: armhf
+      CONFIGURE_ARGS: --disable-sig-sphincs --disable-sig-qtesla # sig-sphincs exhausts memory on CircleCI servers; qTesla fails on armhf
+  debian-buster-armel:
+    <<: *emulatedjob
+    environment:
+      ARCH: armel
+      CONFIGURE_ARGS: --disable-sig-sphincs --disable-sig-qtesla # sig-sphincs exhausts memory on CircleCI servers; qTesla fails on armel
   ubuntu-xenial-x86_64-gcc49:
     <<: *oqsjob
     environment:
@@ -93,6 +132,9 @@ workflows:
                 - master
     jobs:
       - debian-buster-amd64
+      - debian-buster-aarch64
+      - debian-buster-armhf
+      - debian-buster-armel
       - ubuntu-xenial-x86_64-gcc49
       - ubuntu-xenial-x86_64-gcc5
       - ubuntu-xenial-x86_64-gcc6
diff --git a/README.md b/README.md
index 993390747..e9a1e96f6 100644
--- a/README.md
+++ b/README.md
@@ -183,14 +183,13 @@ The supported schemes are defined in the projects' `winconfig.h` file.
 Building and running on ARM
 ---------------------------
 
-Binaries for ARM can be cross-compiled from Ubuntu Linux.  Builds are tested using the Travis continuous integration system on Ubuntu 14.04.5 with QEMU target CPU Cortex-A8.
+Our continuous integration system includes builds on various ARM architectures, see the Testing section below.
 
-In order to cross compile, you need to have an appropriate toolchain installed, and to test you need QEMU installed.  On Ubuntu:
+Binaries for ARM can also be cross-compiled on Linux.  In order to cross compile, you need to have an appropriate toolchain installed, and to test you need QEMU installed.  
+
+For example, to cross compile for ARMv7 (armel) on Ubuntu Linux, first install the required toolchain, then use the scripts below to build and test on an emulated ARM Cortex-A8:
 
 	sudo apt install gcc-arm-linux-gnueabi libc6-dev-armel-cross qemu
-	
-Once the toolchain is installed, you can use the following scripts to build and test ARM builds from Ubuntu Linux:
-
 	scripts/arm-cross-compile.sh
 	scripts/arm-run-tests-qemu.sh
 
@@ -207,7 +206,8 @@ Builds are tested using continuous integration systems as follows:
 - Ubuntu 14.04.5 (Trusty), with gcc, on ARM Cortex-A8 (via QEMU) using Travis CI
 - Ubuntu 16.04.6 (Xenial), with gcc-4.9, gcc-5, gcc-6, gcc-7, and gcc-8, on x86_64 using CircleCI
 - Ubuntu 18.04.2 (Bionic), with gcc-7, on x86_64 using CircleCI
-- Debian 10 (Buster), with gcc-8.3.0, on amd64 using CircleCI
+- Debian 10 (Buster), with gcc-8.3.0, on amd64  using CircleCI
+- Debian 10 (Buster), with gcc-8.3.0, on ARMv8 (aarch64), ARMv7 (armhf, armel) (via QEMU) using CircleCI
 - Windows Server 2016, with Visual Studio 2017, on x86_64 using AppVeyor
 
 Build status:
@@ -216,7 +216,7 @@ Build status:
 - [CircleCI](https://circleci.com/gh/open-quantum-safe/liboqs/tree/master): ![Build status image](https://circleci.com/gh/open-quantum-safe/liboqs/tree/master.svg?style=svg)
 - [Travis CI](https://travis-ci.org/open-quantum-safe/liboqs): ![Build status image](https://travis-ci.org/open-quantum-safe/liboqs.svg?branch=master)
 
-You can locally run any of the integration tests that CircleCI runs.  First, you need to install CircleCI's local command line interface as indicated in the [installation instructions](https://circleci.com/docs/2.0/local-cli/).  Then:
+You can locally run most of the integration tests that CircleCI runs.  First, you need to install CircleCI's local command line interface as indicated in the [installation instructions](https://circleci.com/docs/2.0/local-cli/).  Then:
 
 	circleci local execute --job <jobname>
 
@@ -234,6 +234,8 @@ where `<jobname>` is one of the following:
 
 You may receive an error "Failed uploading test results directory" when running CircleCI locally, that is expected behaviour.
 
+Note that you cannot run "machine" CircleCI builds locally, which are what we use for testing builds on emulated platforms, specifically the ARM `debian-buster-aarch64`, `-armhf`, and `-armel` jobs.
+
 Documentation
 -------------
 
diff --git a/scripts/arm-cross-compile.sh b/scripts/arm-cross-compile.sh
index 1e3e7e8cb..d97428205 100755
--- a/scripts/arm-cross-compile.sh
+++ b/scripts/arm-cross-compile.sh
@@ -25,9 +25,9 @@ cd ..
 autoreconf -i
 hacks=(
 	gcc_cv_compiler=true	# Detecting at this phase isn't good for cross compilation
-	--disable-aes-ni	# This should be conditionalized on x86 host
-    --disable-sig-picnic
 	CFLAGS=-D_ARM_		# Several files aren't using the right define
+	--disable-sig-picnic	# Problems building Picnic using cross compilation
+	--disable-sig-qtesla	# qTesla fails on armhf and armel
 )
 
 ./configure --disable-shared --enable-static --host="${CHOST}" --build="$CBUILD" CC="${CHOST}-gcc" --with-openssl="${PREFIX}" "${hacks[@]}"
diff --git a/src/common/rand_nist.c b/src/common/rand_nist.c
index 3a5d2de27..6d5a85bac 100644
--- a/src/common/rand_nist.c
+++ b/src/common/rand_nist.c
@@ -79,7 +79,7 @@ OQS_API void OQS_randombytes_nist_kat_init(unsigned char *entropy_input, unsigne
 	DRBG_ctx.reseed_counter = 1;
 }
 
-void OQS_randombytes_nist_kat(unsigned char *x, unsigned long long xlen) {
+void OQS_randombytes_nist_kat(unsigned char *x, size_t xlen) {
 	unsigned char block[16];
 	int i = 0;