diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 73e65f7..eb3995d 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -14,24 +14,38 @@ permissions:
   contents: read
 
 jobs:
-  build:
+  test:
 
     name: Build and test
     runs-on: ubuntu-latest
 
+    strategy:
+      fail-fast: false
+      matrix:
+        include:
+          - pair:
+              elixir: 1.12
+              otp: 24
+          - pair:
+              elixir: 1.14
+              otp: 25
+          - pair:
+              elixir: 1.15
+              otp: 26
+
     steps:
     - uses: actions/checkout@v3
     - name: Set up Elixir
       uses: erlef/setup-beam@v1
       with:
-        elixir-version: '1.14.3'
-        otp-version: '25.x'
+        elixir-version: ${{matrix.pair.elixir}}
+        otp-version: ${{matrix.pair.otp}}
     - name: Restore Elixir dependencies cache
       uses: actions/cache@v3
       with:
         path: deps
-        key: ${{ runner.os }}-mix-${{ hashFiles('**/mix.lock') }}
-        restore-keys: ${{ runner.os }}-mix-
+        key: ${{ runner.os }}-mix-${{matrix.pair.elixir}}-${{matrix.pair.otp}}-${{ hashFiles('**/mix.lock') }}
+        restore-keys: ${{ runner.os }}-mix-${{matrix.pair.elixir}}-${{matrix.pair.otp}}-
     - name: Restore Cargo cache
       uses: actions/cache@v3
       with:
diff --git a/test/jsonrs_test.exs b/test/jsonrs_test.exs
index a634083..025fd62 100644
--- a/test/jsonrs_test.exs
+++ b/test/jsonrs_test.exs
@@ -12,6 +12,10 @@ defmodule JsonrsTest do
       assert Jsonrs.encode!({:ok, :error}) == ~s(["ok","error"])
     end
 
+    test "complicated term" do
+      assert Jsonrs.encode!(%{map: %{1 => "foo", "list" => [:ok, 42, -42, 42.0, 42.01, :error], tuple: {:ok, []}, atom: :atom}}) == ~s({"map":{"1":"foo","atom":"atom","tuple":["ok",[]],"list":["ok",42,-42,42.0,42.01,"error"]}})
+    end
+
     test "struct using fallback protocol" do
       assert Jsonrs.encode!(%Container{payload: ~T[12:00:00]}) == ~s({"payload":"12:00:00"})
     end