diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index ddb6ba8..bb85e43 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -16,12 +16,13 @@ jobs:
       fail-fast: false
       matrix:
         include:
-          - pair:
-              elixir: "1.8.2"
-              otp: "21.3.8.17"
-          - pair:
-              elixir: "1.17.3"
-              otp: "27.1"
+          # Oldest-supported Elixir/OTP versions.
+          - elixir: "1.13.4"
+            otp: "22.3.4.27"
+
+          # Latest-supported Elixir/OTP versions.
+          - elixir: "1.17.3"
+            otp: "27.1"
             lint: lint
             coverage: coverage
     steps:
@@ -34,8 +35,8 @@ jobs:
       - name: Install Erlang/OTP and Elixir
         uses: erlef/setup-beam@v1
         with:
-          otp-version: ${{ matrix.pair.otp }}
-          elixir-version: ${{ matrix.pair.elixir }}
+          otp-version: ${{ matrix.otp }}
+          elixir-version: ${{ matrix.elixir }}
 
       - name: Cache Mix dependencies
         uses: actions/cache@v4
@@ -44,9 +45,9 @@ jobs:
             deps
             _build
           key: |
-            ${{ runner.os }}-mix-${{ matrix.pair.elixir }}-${{ matrix.pair.otp }}-${{ hashFiles('**/mix.lock') }}
+            ${{ runner.os }}-mix-${{ matrix.elixir }}-${{ matrix.otp }}-${{ hashFiles('**/mix.lock') }}
           restore-keys: |
-            ${{ runner.os }}-mix-${{ matrix.pair.elixir }}-${{ matrix.pair.otp }}-
+            ${{ runner.os }}-mix-${{ matrix.elixir }}-${{ matrix.otp }}-
 
       - name: Fetch Mix dependencies
         run: mix deps.get
diff --git a/mix.exs b/mix.exs
index 8b372d4..76d3b62 100644
--- a/mix.exs
+++ b/mix.exs
@@ -9,7 +9,7 @@ defmodule BroadwayRabbitMQ.MixProject do
     [
       app: :broadway_rabbitmq,
       version: @version,
-      elixir: "~> 1.8",
+      elixir: "~> 1.13",
       name: "BroadwayRabbitMQ",
       description: @description,
       start_permanent: Mix.env() == :prod,