--- a/taskcluster/taskgraph/transforms/job/toolchain.py
+++ b/taskcluster/taskgraph/transforms/job/toolchain.py
@@ -75,16 +75,17 @@ def add_optimizations(config, run, taskd
 @run_job_using("docker-worker", "toolchain-script", schema=toolchain_run_schema)
 def docker_worker_toolchain(config, job, taskdesc):
     run = job['run']
     taskdesc['run-on-projects'] = ['trunk', 'try']
 
     worker = taskdesc['worker']
     worker['artifacts'] = []
     worker['caches'] = []
+    worker['chain-of-trust'] = True
 
     docker_worker_add_public_artifacts(config, job, taskdesc)
     docker_worker_add_tc_vcs_cache(config, job, taskdesc)
     docker_worker_add_gecko_vcs_env_vars(config, job, taskdesc)
     support_vcs_checkout(config, job, taskdesc)
 
     env = worker['env']
     env.update({
@@ -141,16 +142,17 @@ def windows_toolchain(config, job, taskd
     taskdesc['run-on-projects'] = ['trunk', 'try']
 
     worker = taskdesc['worker']
 
     worker['artifacts'] = [{
         'path': r'public\build',
         'type': 'directory',
     }]
+    worker['chain-of-trust'] = True
 
     docker_worker_add_gecko_vcs_env_vars(config, job, taskdesc)
 
     # We fetch LLVM SVN into this.
     svn_cache = 'level-{}-toolchain-clang-cl-build-svn'.format(config.params['level'])
     worker['mounts'] = [{
         'cache-name': svn_cache,
         'directory': r'llvm-sources',