diff --git a/.circleci/config.yml b/.circleci/config.yml
index ce4da13..347afdf 100644
--- a/.circleci/config.yml
+++ b/.circleci/config.yml
@@ -8,10 +8,55 @@ jobs:
       - run: 
           name: build and test
           command: cargo build && cargo test
+  threefour:
+    docker:
+      - image: circleci/rust:1.34.0
+    steps:
+      - checkout
+      - run:
+          name: build and test
+          command: cargo build && cargo test
+  threethree:
+    docker:
+      - image: circleci/rust:1.33.0
+    steps:
+      - checkout
+      - run:
+          name: build and test
+          command: cargo build && cargo test
+  threetwo:
+    docker:
+      - image: circleci/rust:1.33.0
+    steps:
+      - checkout
+      - run:
+          name: build and test
+          command: cargo build && cargo test
+  threeone:
+    docker:
+      - image: circleci/rust:1.33.0
+    steps:
+      - checkout
+      - run:
+          name: build and test
+          command: cargo build && cargo test
+  threezero:
+    docker:
+      - image: circleci/rust:1.33.0
+    steps:
+      - checkout
+      - run:
+          name: build and test
+          command: cargo build && cargo test
 
 workflows:
   version: 2
   build_and_test:
     jobs:
       - latest
+      - threefour
+      - threethree
+      - threetwo
+      - threeone
+      - threezero