diff --git a/osbase/logtree/BUILD.bazel b/osbase/logtree/BUILD.bazel
new file mode 100644
index 0000000..7c13aeb
--- /dev/null
+++ b/osbase/logtree/BUILD.bazel
@@ -0,0 +1,58 @@
+load("@io_bazel_rules_go//go:def.bzl", "go_library", "go_test")
+
+go_library(
+    name = "logtree",
+    srcs = [
+        "doc.go",
+        "grpc.go",
+        "journal.go",
+        "journal_entry.go",
+        "journal_subscriber.go",
+        "klog.go",
+        "kmsg.go",
+        "leveled.go",
+        "leveled_payload.go",
+        "logtree.go",
+        "logtree_access.go",
+        "logtree_entry.go",
+        "logtree_publisher.go",
+        "testhelpers.go",
+        "zap.go",
+    ],
+    # TODO(#189): move logtree to //go
+    importpath = "source.monogon.dev/osbase/logtree",
+    visibility = ["//visibility:public"],
+    deps = [
+        "//osbase/logbuffer",
+        "//osbase/logtree/proto",
+        "@com_github_mitchellh_go_wordwrap//:go-wordwrap",
+        "@org_golang_google_grpc//grpclog",
+        "@org_golang_google_protobuf//types/known/timestamppb",
+        "@org_uber_go_zap//:zap",
+        "@org_uber_go_zap//zapcore",
+    ] + select({
+        "@io_bazel_rules_go//go/platform:android": [
+            "@org_golang_x_sys//unix",
+        ],
+        "@io_bazel_rules_go//go/platform:linux": [
+            "@org_golang_x_sys//unix",
+        ],
+        "//conditions:default": [],
+    }),
+)
+
+go_test(
+    name = "logtree_test",
+    srcs = [
+        "journal_test.go",
+        "klog_test.go",
+        "kmsg_test.go",
+        "logtree_test.go",
+        "zap_test.go",
+    ],
+    embed = [":logtree"],
+    deps = [
+        "@com_github_google_go_cmp//cmp",
+        "@org_uber_go_zap//:zap",
+    ],
+)