diff --git a/test/circuit_test.rb b/test/circuit_test.rb
index 3f8eb1f..d89d25d 100644
--- a/test/circuit_test.rb
+++ b/test/circuit_test.rb
@@ -20,11 +20,11 @@ class CircuitTest < Minitest::Spec
 
     last_signal, (ctx, i, j, *bla) = circuit.([ctx, 1, 2], task: Start)
 
-    expect(ctx.inspect).must_equal %{{:start=>1, :a=>2, :b=>3, :_end=>4}}
-    expect(last_signal).must_equal "the end"
-    expect(i).must_equal 1
-    expect(j).must_equal 2
-    expect(bla).must_equal []
+    assert_equal ctx.inspect, %{{:start=>1, :a=>2, :b=>3, :_end=>4}}
+    assert_equal last_signal, "the end"
+    assert_equal i, 1
+    assert_equal j, 2
+    assert_equal bla, []
 
     # ---
 
@@ -33,7 +33,7 @@ class CircuitTest < Minitest::Spec
 
     last_signal, (ctx, i, j, *bla) = circuit.([ctx, flow_options, 2], task: Start, runner: MyRunner)
 
-    expect(flow_options).must_equal(stack: [Start, A, B, End])
+    assert_equal flow_options, { stack: [Start, A, B, End] }
   end
 
   MyRunner = ->(task, args, **circuit_options) do
@@ -76,11 +76,11 @@ class CircuitTest < Minitest::Spec
 
     last_signal, (ctx, i, j, *bla) = outer.([ctx, {}, 2], task: Start)
 
-    expect(ctx.inspect).must_equal %{{:start=>1, :a=>2, :c=>6, :_end=>4, :b=>3}}
-    expect(last_signal).must_equal "the end"
-    expect(i).must_equal({})
-    expect(j).must_equal 2
-    expect(bla).must_equal []
+    assert_equal ctx.inspect, %{{:start=>1, :a=>2, :c=>6, :_end=>4, :b=>3}}
+    assert_equal last_signal, "the end"
+    assert_equal i,({})
+    assert_equal j, 2
+    assert_equal bla, []
   end
 
   it "allows using a custom :runner" do
@@ -89,11 +89,11 @@ class CircuitTest < Minitest::Spec
 
     last_signal, (ctx, flow_options, j, *bla) = outer.([ctx, flow_options, 2], task: Start, runner: MyRunner)
 
-    expect(ctx.inspect).must_equal %{{:start=>1, :a=>2, :c=>6, :_end=>4, :b=>3}}
-    expect(last_signal).must_equal "the end"
-    expect(flow_options).must_equal(stack: [Start, A, nestable, Start, C, End, B, End], runner: MyRunner)
-    expect(j).must_equal 2
-    expect(bla).must_equal []
+    assert_equal ctx.inspect, %{{:start=>1, :a=>2, :c=>6, :_end=>4, :b=>3}}
+    assert_equal last_signal, "the end"
+    assert_equal flow_options, { stack: [Start, A, nestable, Start, C, End, B, End], runner: MyRunner }
+    assert_equal j, 2
+    assert_equal bla, []
   end
 
   let(:wicked_circuit) do
diff --git a/test/intermediate_test.rb b/test/intermediate_test.rb
index 8326a23..09dc327 100644
--- a/test/intermediate_test.rb
+++ b/test/intermediate_test.rb
@@ -164,7 +164,7 @@ def implementation(c_extensions)
 
       schema = Inter::Compiler.(intermediate, implementation([ext_a, ext_b, ext_d, ext_e]))
 
-      expect(schema[:config].to_h.inspect).must_equal %{{:wrap_static=>{}, :a=>\"bla\", :b=>\"blubb\", :C=>1, :e=>2}}
+      assert_equal schema[:config].to_h.inspect, %{{:wrap_static=>{}, :a=>\"bla\", :b=>\"blubb\", :C=>1, :e=>2}}
     end
 
   # {Implementation.call()} allows to pass {config} data
@@ -172,13 +172,13 @@ def implementation(c_extensions)
       it "accepts {config_merge:} data that is merged into {config}" do
         schema = Inter::Compiler.(intermediate, implementation([]), config_merge: {beer: "yes"})
 
-        expect(schema[:config].to_h.inspect).must_equal %{{:wrap_static=>{}, :beer=>\"yes\"}}
+        assert_equal schema[:config].to_h.inspect, %{{:wrap_static=>{}, :beer=>\"yes\"}}
       end
 
       it "{:config_merge} overrides values in {default_config}" do
         schema = Inter::Compiler.(intermediate, implementation([]), config_merge: {beer: "yes", wrap_static: "yo"})
 
-        expect(schema[:config].to_h.inspect).must_equal %{{:wrap_static=>"yo", :beer=>\"yes\"}}
+        assert_equal schema[:config].to_h.inspect, %{{:wrap_static=>"yo", :beer=>\"yes\"}}
       end
     end
   end
diff --git a/test/structures_test.rb b/test/structures_test.rb
index 68d8153..c4d5cde 100644
--- a/test/structures_test.rb
+++ b/test/structures_test.rb
@@ -7,23 +7,23 @@ class StructuresTest < Minitest::Spec
     it "#call always returns the End instance itself" do
       signal, (_ctx, _flow_options) = evt.([{a: 1}, {}])
 
-      expect(signal).must_equal evt
+      assert_equal signal, evt
     end
 
     it "responds to #to_h" do
-      expect(evt.to_h).must_equal({semantic: :meaning})
+      assert_equal evt.to_h, {semantic: :meaning}
     end
 
     it "has strict object identity" do
-      expect(evt).wont_equal Activity::End(:meaning)
+      refute_equal evt, Activity::End(:meaning)
     end
 
     it "responds to #inspect" do
-      expect(evt.inspect).must_equal %{#<Trailblazer::Activity::End semantic=:meaning>}
+      assert_equal evt.inspect, %(#<Trailblazer::Activity::End semantic=:meaning>)
     end
 
     it "allows more variables" do
-      expect(Activity::End.new(semantic: :success, type: :event).to_h).must_equal(semantic: :success, type: :event)
+      assert_equal Activity::End.new(semantic: :success, type: :event).to_h, { semantic: :success, type: :event }
     end
   end
 end