diff --git a/tests/unit/base.cc b/tests/unit/base.cc
deleted file mode 100644
index 4573678..0000000
--- a/tests/unit/base.cc
+++ /dev/null
@@ -1,5 +0,0 @@
-#include <gtest/gtest.h>
-
-TEST(misc, passing) {
-    ASSERT_EQ(1, 1);
-}
diff --git a/tests/unit/bignum.cc b/tests/unit/bignum.cc
new file mode 100644
index 0000000..e7dfdc6
--- /dev/null
+++ b/tests/unit/bignum.cc
@@ -0,0 +1,27 @@
+#include <gtest/gtest.h>
+
+#include "bignum.hh"
+
+using namespace abacus::bignum;
+
+TEST(BigNum, equality) {
+    auto const zero = BigNum(0);
+    auto const one = BigNum(1);
+
+    ASSERT_EQ(zero, zero);
+    ASSERT_EQ(one, one);
+    ASSERT_NE(zero, one);
+}
+
+TEST(BigNum, comparisons) {
+    auto const zero = BigNum(0);
+    auto const one = BigNum(1);
+
+    ASSERT_LT(zero, one);
+    ASSERT_LE(zero, one);
+    ASSERT_LE(zero, zero);
+
+    ASSERT_GT(one, zero);
+    ASSERT_GE(one, zero);
+    ASSERT_GE(one, one);
+}
diff --git a/tests/unit/meson.build b/tests/unit/meson.build
index e866754..db8eddd 100644
--- a/tests/unit/meson.build
+++ b/tests/unit/meson.build
@@ -6,13 +6,14 @@ gtest = dependency(
 
 if gtest.found()
   unit_test_sources = files(
-    'base.cc',
+    'bignum.cc',
   )
 
   unit_tests = executable(
     'unit_tests',
     sources: unit_test_sources,
     dependencies: [
+      bignum,
       gtest,
     ],
   )