diff --git a/packages/agentos-toolchain/package.json b/packages/agentos-toolchain/package.json
index b3d3dea8c9..0a4bd64de5 100644
--- a/packages/agentos-toolchain/package.json
+++ b/packages/agentos-toolchain/package.json
@@ -33,6 +33,6 @@
 		"vitest": "^2.1.9"
 	},
 	"dependencies": {
-		"@bare-ts/lib": "^0.4.0"
+		"@bare-ts/lib": "^0.4.1"
 	}
 }
diff --git a/packages/core/package.json b/packages/core/package.json
index a4b16430f3..fa4fe17864 100644
--- a/packages/core/package.json
+++ b/packages/core/package.json
@@ -67,7 +67,7 @@
 		"zod": "^4.1.11"
 	},
 	"devDependencies": {
-		"@bare-ts/lib": "^0.4.0",
+		"@bare-ts/lib": "^0.4.1",
 		"@agentos-software/common": "workspace:*",
 		"@agentos-software/coreutils": "workspace:*",
 		"@agentos-software/curl": "workspace:*",
diff --git a/packages/core/tests/filesystem-large-payload.test.ts b/packages/core/tests/filesystem-large-payload.test.ts
new file mode 100644
index 0000000000..7137631d03
--- /dev/null
+++ b/packages/core/tests/filesystem-large-payload.test.ts
@@ -0,0 +1,21 @@
+import { afterEach, beforeEach, expect, test } from "vitest";
+import { AgentOs } from "../src/index.js";
+
+let vm: AgentOs;
+
+beforeEach(async () => {
+	vm = await AgentOs.create({ defaultSoftware: false });
+});
+
+afterEach(async () => {
+	await vm.dispose();
+});
+
+test("a file larger than one encoder buffer round-trips through the sidecar", async () => {
+	const content = new Uint8Array(256 * 1024).map((_, index) => index % 251);
+
+	await vm.filesystem.writeFile("/tmp/large.bin", content);
+
+	const roundTripped = await vm.filesystem.readFile("/tmp/large.bin");
+	expect(new Uint8Array(roundTripped)).toEqual(content);
+}, 60_000);
diff --git a/packages/runtime-core/package.json b/packages/runtime-core/package.json
index ff2cc0443d..16d10bc225 100644
--- a/packages/runtime-core/package.json
+++ b/packages/runtime-core/package.json
@@ -208,7 +208,7 @@
 	},
 	"dependencies": {
 		"@rivet-dev/agentos-runtime-sidecar": "workspace:*",
-		"@bare-ts/lib": "^0.4.0",
+		"@bare-ts/lib": "^0.4.1",
 		"zod": "^4.1.11",
 		"zod-to-json-schema": "^3.25.2"
 	},
diff --git a/pnpm-lock.yaml b/pnpm-lock.yaml
index 0ce062a52f..ea0b80f178 100644
--- a/pnpm-lock.yaml
+++ b/pnpm-lock.yaml
@@ -815,8 +815,8 @@ importers:
   packages/agentos-toolchain:
     dependencies:
       '@bare-ts/lib':
-        specifier: ^0.4.0
-        version: 0.4.0
+        specifier: ^0.4.1
+        version: 0.4.1
     devDependencies:
       '@types/node':
         specifier: ^22.10.2
@@ -835,7 +835,7 @@ importers:
     dependencies:
       '@bare-ts/tools':
         specifier: 0.15.0
-        version: 0.15.0(@bare-ts/lib@0.4.0)
+        version: 0.15.0(@bare-ts/lib@0.4.1)
       '@exodus/bytes':
         specifier: 1.15.1
         version: 1.15.1(@noble/hashes@2.2.0)
@@ -946,8 +946,8 @@ importers:
         specifier: workspace:*
         version: link:../../software/yq
       '@bare-ts/lib':
-        specifier: ^0.4.0
-        version: 0.4.0
+        specifier: ^0.4.1
+        version: 0.4.1
       '@browserbasehq/browse-cli':
         specifier: 0.5.0
         version: 0.5.0(@cfworker/json-schema@4.1.1)(@opentelemetry/api@1.9.0)(bufferutil@4.1.0)(deepmerge@4.3.1)(zod@4.3.6)
@@ -1069,8 +1069,8 @@ importers:
   packages/runtime-core:
     dependencies:
       '@bare-ts/lib':
-        specifier: ^0.4.0
-        version: 0.4.0
+        specifier: ^0.4.1
+        version: 0.4.1
       '@rivet-dev/agentos-runtime-sidecar':
         specifier: workspace:*
         version: link:../runtime-sidecar
@@ -2248,8 +2248,8 @@ packages:
   '@balena/dockerignore@1.0.2':
     resolution: {integrity: sha512-wMue2Sy4GAVTk6Ic4tJVcnfdau+gx2EnG7S+uAEe+TWJFqE4YoWN4/H8MSLj4eYJKxGg26lZwboEniNiNwZQ6Q==}
 
-  '@bare-ts/lib@0.4.0':
-    resolution: {integrity: sha512-uTb12lcDkvwwwGb/4atNy/+2Xuksx88tlxKuwnDuxmsOFVo4R/WsE+fmAf2nWtzHDi7m6NDw8Ke9j+XlNBLoJg==}
+  '@bare-ts/lib@0.4.1':
+    resolution: {integrity: sha512-G9RnojF6PJjAF6ULnlOc2C10gnCk0jgywZXxVhxDH2Kw4pCNdf0jGk+bYm1kIE9VbzJ9m5iG53mT92jXTCzPzA==}
     engines: {node: ^14.18.0 || >=16.0.0}
 
   '@bare-ts/tools@0.15.0':
@@ -6227,11 +6227,11 @@ snapshots:
 
   '@balena/dockerignore@1.0.2': {}
 
-  '@bare-ts/lib@0.4.0': {}
+  '@bare-ts/lib@0.4.1': {}
 
-  '@bare-ts/tools@0.15.0(@bare-ts/lib@0.4.0)':
+  '@bare-ts/tools@0.15.0(@bare-ts/lib@0.4.1)':
     dependencies:
-      '@bare-ts/lib': 0.4.0
+      '@bare-ts/lib': 0.4.1
       commander: 11.1.0
 
   '@biomejs/biome@2.4.10':