diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index b4eae4f..c3dd15d 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -12,7 +12,7 @@ jobs:
     runs-on: ubuntu-latest
 
     container:
-      image: elixir:1.10.0-alpine
+      image: elixir:1.9.4-alpine
 
     steps:
       - uses: actions/checkout@v1
@@ -35,7 +35,7 @@ jobs:
     runs-on: ubuntu-latest
 
     container:
-      image: elixir:1.10.0-alpine
+      image: elixir:1.9.4-alpine
 
     steps:
       - uses: actions/checkout@v1
@@ -55,7 +55,7 @@ jobs:
     runs-on: ubuntu-latest
 
     container:
-      image: elixir:1.10.0-alpine
+      image: elixir:1.9.4-alpine
 
     steps:
       - uses: actions/checkout@v1
@@ -83,7 +83,7 @@ jobs:
     runs-on: ubuntu-latest
 
     container:
-      image: elixir:1.10.0-alpine
+      image: elixir:1.9.4-alpine
 
     steps:
       - uses: actions/checkout@v1
@@ -106,7 +106,7 @@ jobs:
     runs-on: ubuntu-latest
 
     container:
-      image: elixir:1.10.0-alpine
+      image: elixir:1.9.4-alpine
 
     env:
       MIX_ENV: dev
diff --git a/.tool-versions b/.tool-versions
index 71f8556..d76f460 100644
--- a/.tool-versions
+++ b/.tool-versions
@@ -1,2 +1,2 @@
-elixir 1.10.0-otp-22
+elixir 1.9.4-otp-22
 erlang 22.2.3