diff --git a/tests/unit/libstore/filetransfer.cc b/tests/unit/libstore/filetransfer.cc
index 5885a8059..15c378391 100644
--- a/tests/unit/libstore/filetransfer.cc
+++ b/tests/unit/libstore/filetransfer.cc
@@ -37,7 +37,7 @@ namespace nix {
 static std::tuple<uint16_t, AutoCloseFD>
 serveHTTP(std::vector<Reply> replies)
 {
-    AutoCloseFD listener(::socket(AF_INET6, SOCK_STREAM, 0));
+    AutoCloseFD listener(::socket(AF_INET, SOCK_STREAM, 0));
     if (!listener) {
         throw SysError(errno, "socket() failed");
     }
@@ -46,7 +46,7 @@ serveHTTP(std::vector<Reply> replies)
     trigger.create();
 
     sockaddr_in6 addr = {
-        .sin6_family = AF_INET6,
+        .sin6_family = AF_INET,
         .sin6_addr = IN6ADDR_LOOPBACK_INIT,
     };
     socklen_t len = sizeof(addr);
@@ -155,7 +155,7 @@ TEST(FileTransfer, exceptionAbortsRead)
     auto [port, srv] = serveHTTP("200 ok", "content-length: 0\r\n", [] { return ""; });
     auto ft = makeFileTransfer();
     char buf[10] = "";
-    ASSERT_THROW(ft->download(fmt("http://[::1]:%d/index", port)).second->read(buf, 10), EndOfFile);
+    ASSERT_THROW(ft->download(fmt("http://127.0.0.1:%d/index", port)).second->read(buf, 10), EndOfFile);
 }
 
 TEST(FileTransfer, NOT_ON_DARWIN(reportsSetupErrors))
@@ -163,7 +163,7 @@ TEST(FileTransfer, NOT_ON_DARWIN(reportsSetupErrors))
     auto [port, srv] = serveHTTP("404 not found", "", [] { return ""; });
     auto ft = makeFileTransfer();
     ASSERT_THROW(
-        ft->download(fmt("http://[::1]:%d/index", port)),
+        ft->download(fmt("http://127.0.0.1:%d/index", port)),
         FileTransferError
     );
 }
@@ -179,7 +179,7 @@ TEST(FileTransfer, NOT_ON_DARWIN(defersFailures))
         return std::string(1024 * 1024, ' ');
     });
     auto ft = makeFileTransfer(0);
-    auto src = ft->download(fmt("http://[::1]:%d/index", port)).second;
+    auto src = ft->download(fmt("http://127.0.0.1:%d/index", port)).second;
     ASSERT_THROW(src->drain(), FileTransferError);
 }
 
@@ -192,7 +192,7 @@ TEST(FileTransfer, NOT_ON_DARWIN(handlesContentEncoding))
     auto ft = makeFileTransfer();
 
     StringSink sink;
-    ft->download(fmt("http://[::1]:%d/index", port)).second->drainInto(sink);
+    ft->download(fmt("http://127.0.0.1:%d/index", port)).second->drainInto(sink);
     EXPECT_EQ(sink.s, original);
 }
 
@@ -215,7 +215,7 @@ TEST(FileTransfer, usesIntermediateLinkHeaders)
         {"200 ok", "content-length: 1\r\n", [] { return "a"; }},
     });
     auto ft = makeFileTransfer(0);
-    auto [result, _data] = ft->download(fmt("http://[::1]:%d/first", port));
+    auto [result, _data] = ft->download(fmt("http://127.0.0.1:%d/first", port));
     ASSERT_EQ(result.immutableUrl, "http://foo");
 }