diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index e0a3c28..17288d8 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -1,6 +1,6 @@
 name: Continuous Integration
 
-on: [push, pull_request]
+on: [push, pull_request, workflow_dispatch]
 
 jobs:
   build:
diff --git a/.github/workflows/nightly.yml b/.github/workflows/nightly.yml
index 8263897..19a1b0d 100644
--- a/.github/workflows/nightly.yml
+++ b/.github/workflows/nightly.yml
@@ -4,13 +4,21 @@ on:
   schedule:
     # Every night at midnight
     - cron:  '0 0 * * *'
-
+  workflow_dispatch:
+    inputs:
+      rev:
+        description: "Revision hash to run against"
+        required: false
+        default: ""
+        
 jobs:
   dependencies:
     name: Check for unused dependencies
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v2
+        with:
+          ref: "${{ github.event.inputs.rev }}"
       - name: Install latest Rust
         uses: actions-rs/toolchain@v1
         with:
@@ -27,6 +35,8 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v2
+        with:
+          ref: "${{ github.event.inputs.rev }}"
       - name: Install latest Rust
         uses: actions-rs/toolchain@v1
         with: