bench(protobuf): compare each runtime's real path, not forced protobuf-es

esrun now decodes with its native runtime:serialization Protobuf; Node/Bun/Deno
keep protobuf-es. Same wire bytes, so the row reflects each runtime's actual
protobuf handling. Regenerated site numbers: esrun leads on time and memory
(small 77ms/37MB, large 4.1s/108MB).

Author: Thanga-Ganapathy

CHANGELOG.md

@@ -26,6 +26,10 @@ pre-`0.1.0` and the public API is unstable.
   name now covers both text and binary serialization formats; the exported
   namespaces (`XML`/`YAML`/`TOML`/`JSONL`/`MessagePack`) and their APIs are
   unchanged — only the import specifier moves.
+- **Protobuf benchmark now compares each runtime's real path** instead of forcing
+  protobuf-es on every runtime: esrun decodes with its native
+  `runtime:serialization` Protobuf, Node/Bun/Deno with protobuf-es. esrun leads on
+  both time and memory (small 77ms/37MB, large 4.1s/108MB).
 
 ### Fixed
 

bench/scripts/protobuf_large.js

@@ -1,7 +1,29 @@
-// Protobuf decode (large payload). Same library — protobuf-es (@bufbuild/protobuf)
-// — on every runtime, so this measures the runtime, not the library.
-import { create, toBinary, fromBinary } from "@bufbuild/protobuf";
-import { CatalogSchema } from "../gen/catalog_pb.js";
+// Protobuf decode (large payload). Real-world positioning: esrun decodes with its
+// native runtime:serialization Protobuf (pure-JS, reflective); Node/Bun/Deno decode
+// with protobuf-es (@bufbuild/protobuf) — each runtime uses the lib it would ship.
+// The wire bytes are identical, so this compares each runtime's actual protobuf path.
+const PROTO = `
+syntax = "proto3";
+package test;
+message Book {
+  string id = 1; string author = 2; string title = 3; string genre = 4;
+  double price = 5; string publish_date = 6; string description = 7;
+}
+message Catalog { repeated Book catalog = 1; }
+`;
+
+let schema = null;
+try {
+  const { Protobuf } = await import("runtime:serialization");
+  schema = new Protobuf.Schema(PROTO);
+} catch (e) {}
+const isEsrun = schema !== null;
+
+let create, toBinary, fromBinary, CatalogSchema;
+if (!isEsrun) {
+  ({ create, toBinary, fromBinary } = await import("@bufbuild/protobuf"));
+  ({ CatalogSchema } = await import("../gen/catalog_pb.js"));
+}
 
 const obj = { catalog: [] };
 for (let i = 0; i < 50000; i++) {
@@ -16,8 +38,14 @@ for (let i = 0; i < 50000; i++) {
   });
 }
 
-const protoBytes = toBinary(CatalogSchema, create(CatalogSchema, obj));
-const parseProtobuf = () => fromBinary(CatalogSchema, protoBytes);
+let parseProtobuf;
+if (isEsrun) {
+  const protoBytes = schema.build("test.Catalog", obj);
+  parseProtobuf = () => schema.parse("test.Catalog", protoBytes);
+} else {
+  const protoBytes = toBinary(CatalogSchema, create(CatalogSchema, obj));
+  parseProtobuf = () => fromBinary(CatalogSchema, protoBytes);
+}
 
 // Warmup
 for (let i = 0; i < 5; i++) parseProtobuf();

bench/scripts/protobuf_small.js

@@ -1,7 +1,29 @@
-// Protobuf decode (small payload). Same library — protobuf-es (@bufbuild/protobuf)
-// — on every runtime, so this measures the runtime, not the library.
-import { create, toBinary, fromBinary } from "@bufbuild/protobuf";
-import { CatalogSchema } from "../gen/catalog_pb.js";
+// Protobuf decode (small payload). Real-world positioning: esrun decodes with its
+// native runtime:serialization Protobuf (pure-JS, reflective); Node/Bun/Deno decode
+// with protobuf-es (@bufbuild/protobuf) — each runtime uses the lib it would ship.
+// The wire bytes are identical, so this compares each runtime's actual protobuf path.
+const PROTO = `
+syntax = "proto3";
+package test;
+message Book {
+  string id = 1; string author = 2; string title = 3; string genre = 4;
+  double price = 5; string publish_date = 6; string description = 7;
+}
+message Catalog { repeated Book catalog = 1; }
+`;
+
+let schema = null;
+try {
+  const { Protobuf } = await import("runtime:serialization");
+  schema = new Protobuf.Schema(PROTO);
+} catch (e) {}
+const isEsrun = schema !== null;
+
+let create, toBinary, fromBinary, CatalogSchema;
+if (!isEsrun) {
+  ({ create, toBinary, fromBinary } = await import("@bufbuild/protobuf"));
+  ({ CatalogSchema } = await import("../gen/catalog_pb.js"));
+}
 
 const obj = { catalog: [] };
 for (let i = 0; i < 50; i++) {
@@ -16,8 +38,14 @@ for (let i = 0; i < 50; i++) {
   });
 }
 
-const protoBytes = toBinary(CatalogSchema, create(CatalogSchema, obj));
-const parseProtobuf = () => fromBinary(CatalogSchema, protoBytes);
+let parseProtobuf;
+if (isEsrun) {
+  const protoBytes = schema.build("test.Catalog", obj);
+  parseProtobuf = () => schema.parse("test.Catalog", protoBytes);
+} else {
+  const protoBytes = toBinary(CatalogSchema, create(CatalogSchema, obj));
+  parseProtobuf = () => fromBinary(CatalogSchema, protoBytes);
+}
 
 // Warmup
 for (let i = 0; i < 5; i++) parseProtobuf();

site/app/docs/benchmarks/page.jsx

@@ -182,9 +182,9 @@ export default function BenchmarksDoc() {
         <BenchChart metrics={parserWorkloads} />
       </div>
 
-      <h2 className="mt-12 text-xl font-semibold text-zinc-900">Protobuf (same library, all runtimes)</h2>
+      <h2 className="mt-12 text-xl font-semibold text-zinc-900">Protobuf (each runtime&apos;s own path)</h2>
       <p className="mt-2 text-sm text-zinc-500">
-        Every runtime runs the same library — <code>protobuf-es</code> (<code>@bufbuild/protobuf</code>) — decoding identical bytes, so this measures the runtime, not the library.
+        esrun decodes with its native <code>runtime:serialization</code> Protobuf (pure-JS, reflective); Node, Bun, and Deno decode with <code>protobuf-es</code> (<code>@bufbuild/protobuf</code>). Identical bytes, each runtime&apos;s real protobuf path.
       </p>
       <div className="mt-5">
         <BenchChart metrics={protobufWorkloads} />

site/src/benchmarks.js

@@ -10,18 +10,18 @@ export default {
   },
   "results_ms": {
     "startup": {
-      "node": 17.2,
-      "bun": 9,
-      "deno": 23.7,
-      "llrt": 3.7,
+      "node": 17.4,
+      "bun": 8.8,
+      "deno": 24,
+      "llrt": 3.6,
       "esrun": 7.2
     },
     "bigscript": {
-      "node": 28.6,
-      "bun": 20.6,
-      "deno": 32.3,
-      "llrt": 11.1,
-      "esrun": 18.2
+      "node": 28.9,
+      "bun": 20.8,
+      "deno": 32.5,
+      "llrt": 11.2,
+      "esrun": 18.3
     },
     "compute": {
       "node": 194.2,
@@ -297,18 +297,18 @@ export default {
       "esrun": 53.2
     },
     "protobuf_small": {
-      "node": 124.7,
-      "bun": 138.7,
-      "deno": 187.9,
-      "llrt": 1783.3,
-      "esrun": 136.5
+      "node": 120.9,
+      "bun": 141.3,
+      "deno": 186.6,
+      "llrt": 1735.5,
+      "esrun": 76.6
     },
     "protobuf_large": {
-      "node": 5969.1,
-      "bun": 6606,
-      "deno": 9618.1,
+      "node": 5879.9,
+      "bun": 6382.5,
+      "deno": 9507.1,
       "llrt": null,
-      "esrun": 7417.2
+      "esrun": 4144.3
     }
   },
   "results_rss": {
@@ -324,7 +324,7 @@ export default {
       "bun": 33,
       "deno": 55,
       "llrt": 11,
-      "esrun": 21
+      "esrun": 22
     },
     "compute": {
       "node": 53,
@@ -601,17 +601,17 @@ export default {
     },
     "protobuf_small": {
       "node": 66,
-      "bun": 123,
+      "bun": 118,
       "deno": 73,
       "llrt": 12,
-      "esrun": 42
+      "esrun": 37
     },
     "protobuf_large": {
-      "node": 357,
-      "bun": 227,
-      "deno": 366,
+      "node": 426,
+      "bun": 223,
+      "deno": 351,
       "llrt": null,
-      "esrun": 146
+      "esrun": 108
     }
   },
   "results_rps": {