diff --git a/Vagrantfile b/Vagrantfile
index 15a539b7..1b0cbd0c 100644
--- a/Vagrantfile
+++ b/Vagrantfile
@@ -94,7 +94,8 @@ Vagrant.configure(2) do |config|
       adduser vagrant docker
 
       #add steamrt docker
-      docker build -t "steam-proton-dev" -f "/home/vagrant/proton/steamrt/com.valvesoftware.SteamRuntime.Sdk-amd64,i386-soldier-sysroot.Dockerfile" /home/vagrant/proton/steamrt/
+      docker pull registry.gitlab.steamos.cloud/steamrt/soldier/sdk
+      docker image tag registry.gitlab.steamos.cloud/steamrt/soldier/sdk steam-proton-dev
 
       #allow user to run stuff in steamrt
       sysctl kernel.unprivileged_userns_clone=1
diff --git a/build/makefile_base.mak b/build/makefile_base.mak
index d65fd6d2..b139c42f 100644
--- a/build/makefile_base.mak
+++ b/build/makefile_base.mak
@@ -76,34 +76,31 @@ cc-option = $(shell if test -z "`echo 'void*p=1;' | \
               then echo "$(2)"; else echo "$(3)"; fi ;)
 
 # Selected container mode shell
-DOCKER_SHELL_BASE = docker run --rm --init --privileged --cap-add=SYS_ADMIN --security-opt apparmor:unconfined \
+DOCKER_BASE = docker run --rm --init --privileged --cap-add=SYS_ADMIN --security-opt apparmor:unconfined \
                                     -v $(HOME):$(HOME) -v /tmp:/tmp \
                                     -v /etc/passwd:/etc/passwd:ro -v /etc/group:/etc/group:ro  -v /etc/shadow:/etc/shadow:ro \
                                     -w $(CURDIR) -e HOME=$(HOME) -e PATH=$(PATH) $(DOCKER_CCACHE_FLAG) -u $(shell id -u):$(shell id -g) -h $(shell hostname) \
                                     $(DOCKER_OPTS) \
-                                    $(SELECT_DOCKER_IMAGE) /sbin/docker-init -sg -- /bin/bash
+                                    $(SELECT_DOCKER_IMAGE) /sbin/docker-init -sg --
+
+STEAM_RUNTIME_RUNSH :=
 
 # If STEAMRT64_MODE/STEAMRT32_MODE is set, set the nested SELECT_DOCKER_IMAGE to the _IMAGE variable and eval
-# DOCKER_SHELL_BASE with it to create the CONTAINER_SHELL setting.
+# DOCKER_BASE with it to create the CONTAINER_SHELL setting.
 ifeq ($(STEAMRT64_MODE),docker)
 	SELECT_DOCKER_IMAGE := $(STEAMRT64_IMAGE)
-	CONTAINER_SHELL64 := $(DOCKER_SHELL_BASE)
+	CONTAINER_SHELL64 := $(DOCKER_BASE) /bin/bash
+	STEAM_RUNTIME_RUNSH := $(DOCKER_BASE)
 else ifneq ($(STEAMRT64_MODE),)
 	foo := $(error Unrecognized STEAMRT64_MODE $(STEAMRT64_MODE))
 endif
 ifeq ($(STEAMRT32_MODE),docker)
 	SELECT_DOCKER_IMAGE := $(STEAMRT32_IMAGE)
-	CONTAINER_SHELL32 := $(DOCKER_SHELL_BASE)
+	CONTAINER_SHELL32 := $(DOCKER_BASE) /bin/bash
 else ifneq ($(STEAMRT32_MODE),)
 	foo := $(error Unrecognized STEAMRT32_MODE $(STEAMRT32_MODE))
 endif
 
-ifneq ($(STEAMRT_PATH),)
-	STEAM_RUNTIME_RUNSH := $(STEAMRT_PATH)/run-in-soldier --
-else
-	STEAM_RUNTIME_RUNSH :=
-endif
-
 SELECT_DOCKER_IMAGE :=
 
 # If we're using containers to sub-invoke the various builds, jobserver won't work, have some silly auto-jobs
diff --git a/default_pfx.py b/default_pfx.py
index ba0c759a..7985cd8c 100755
--- a/default_pfx.py
+++ b/default_pfx.py
@@ -70,32 +70,28 @@ def setup_dll_symlinks(default_pfx_dir, dist_dir):
                 os.unlink(filename)
                 make_relative_symlink(target, filename)
 
-def get_runtime_ld_path(runtime):
-    env = subprocess.check_output(runtime + ["env"], text=True)
-    for line in env.splitlines():
-        if line.startswith("LD_LIBRARY_PATH"):
-            return line.split("=", maxsplit=1)[1]
-    return None
-
 def make_default_pfx(default_pfx_dir, dist_dir, runtime):
     local_env = dict(os.environ)
-    local_env["WINEPREFIX"] = default_pfx_dir
-    local_env["WINEDEBUG"] = "-all"
 
     ld_path = dist_dir + "/lib64:" + dist_dir + "/lib"
 
     if runtime is None:
         local_env["LD_LIBRARY_PATH"] = ld_path
+        local_env["WINEPREFIX"] = default_pfx_dir
+        local_env["WINEDEBUG"] = "-all"
         runtime_args = []
     else:
-        #the runtime overwrites LD_LIBRARY_PATH, so we pass it in on the CL via env
-        runtime_ld_path = get_runtime_ld_path(runtime)
-        if not runtime_ld_path is None:
-            ld_path = ld_path + ":" + runtime_ld_path
-        runtime_args = runtime + ["env", "LD_LIBRARY_PATH=" + ld_path]
+        #the runtime clears the environment, so we pass it in on the CL via env
+        runtime_args = runtime + ["env",
+                "LD_LIBRARY_PATH=" + ld_path,
+                "WINEPREFIX=" + default_pfx_dir,
+                "WINEDEBUG=-all"]
 
-    subprocess.run(runtime_args + [os.path.join(dist_dir, 'bin', 'wine'), "wineboot"], env=local_env, check=True)
-    subprocess.run(runtime_args + [os.path.join(dist_dir, 'bin', 'wineserver'), "-w"], env=local_env, check=True)
+    subprocess.run(runtime_args + ["/bin/bash", "-c",
+        os.path.join(dist_dir, 'bin', 'wine') + " wineboot && " +
+        os.path.join(dist_dir, 'bin', 'wineserver') + " -w"],
+
+        env=local_env, check=True)
     setup_dll_symlinks(default_pfx_dir, dist_dir)
 
 if __name__ == '__main__':