diff --git a/.circleci/config.yml b/.circleci/config.yml
index 856542b..be3a30f 100644
--- a/.circleci/config.yml
+++ b/.circleci/config.yml
@@ -8,7 +8,6 @@ jobs:
 
     steps:
       - checkout
-
       - run:
           command: nix-channel --add https://nixos.org/channels/nixpkgs-unstable
       - run:
@@ -16,69 +15,30 @@ jobs:
       - run:
           command: nix-env -i diffutils
 
-      - run:
-          name: Day1
-          command: |
-              nix-instantiate --eval 01/1.nix > /tmp/output1
-              diff /tmp/output1 01/output
-
-      - run:
-          name: Day2
-          command: |
-              nix-instantiate --eval 02/2.nix > /tmp/output2
-              diff /tmp/output2 02/output
-
-      - run:
-          name: Day3
-          command: |
-              nix-instantiate --eval 03/3.nix > /tmp/output3
-              diff /tmp/output3 03/output
-
-      - run:
-          name: Day4
-          command: |
-              nix-instantiate --eval 04/4.nix > /tmp/output4
-              diff /tmp/output4 04/output
-
-      - run:
-          name: Day5
-          command: |
-              nix-instantiate --eval 05/5.nix > /tmp/output5
-              diff /tmp/output5 05/output
-
-      - run:
-          name: Day6
-          command: |
-              nix-instantiate --eval 06/6.nix > /tmp/output6
-              diff /tmp/output6 06/output
+      - persist_to_workspace:
+          root: /
+          paths: "*"
 
-      - run:
-          name: Day7
-          command: |
-              nix-instantiate --eval 07/7.nix > /tmp/output7
-              diff /tmp/output7 07/output
+  day01:
+    docker:
+      - image: nixos/nix
+    working_directory: ~/project/01
 
+    steps:
+      - checkout
+      - attach_workspace:
+          at: /nix/store
       - run:
-          name: Day8
+          name: Check Result
           command: |
-              nix-instantiate --eval 08/8.nix > /tmp/output8
-              diff /tmp/output8 08/output
-
-      # - run:
-      #     name: Day9
-      #     command: |
-      #         nix-instantiate --eval 09/9.nix > /tmp/output9
-      #         diff /tmp/output9 09/output
-
-      # - run:
-      #     name: Day10
-      #     command: |
-      #         nix-instantiate --eval 10/10.nix > /tmp/output10
-      #         diff /tmp/output10 10/output
-
+            nix-instantiate --eval *.nix > /tmp/output
+            diff /tmp/output output
 
 workflows:
   version: 2
-  build:
+  test-workflow:
     jobs:
       - build
+      - day01:
+          requires:
+            - build