diff --git a/flatdeb-builder/Dockerfile b/flatdeb-builder/Dockerfile
index 2116cbe750e26b171eb1bdd8c02976397e7d09da..c8e018e1f5d4f32fcad203b3cd250cd0c5a84932 100644
--- a/flatdeb-builder/Dockerfile
+++ b/flatdeb-builder/Dockerfile
@@ -17,7 +17,8 @@ RUN apt-get update && \
         libostree-dev && \
     rm -rf /var/lib/apt/lists/*
 RUN go get -v -d github.com/go-debos/debos/cmd/debos
-RUN git -C ${GOPATH}/src/github.com/go-debos/fakemachine checkout wip/uml && \
+RUN git -C ${GOPATH}/src/github.com/go-debos/debos checkout -b uml d2ab9d3b08056c416bfbcd63c01199e14b2fc3b9 && \
+    git -C ${GOPATH}/src/github.com/go-debos/fakemachine checkout wip/uml && \
     go install github.com/go-debos/debos/cmd/debos
 
 # Build the slirp helpers, needed by UML for unprivileged networking
diff --git a/image-builder/Dockerfile b/image-builder/Dockerfile
index a9e5e1e48fe0ee6df4a72e901a98ddcf389fa937..c01bf872393afc25623ddae41ca4d6db222dd653 100644
--- a/image-builder/Dockerfile
+++ b/image-builder/Dockerfile
@@ -17,7 +17,8 @@ RUN apt-get update && \
         libostree-dev && \
     rm -rf /var/lib/apt/lists/*
 RUN go get -v -d github.com/go-debos/debos/cmd/debos
-RUN git -C ${GOPATH}/src/github.com/go-debos/fakemachine checkout wip/uml && \
+RUN git -C ${GOPATH}/src/github.com/go-debos/debos checkout -b uml d2ab9d3b08056c416bfbcd63c01199e14b2fc3b9 && \
+    git -C ${GOPATH}/src/github.com/go-debos/fakemachine checkout wip/uml && \
     go install github.com/go-debos/debos/cmd/debos
 
 # Build the slirp helpers, needed by UML for unprivileged networking