diff --git a/docs/local-dev.md b/docs/local-dev.md
index 462128b..905c74c 100644
--- a/docs/local-dev.md
+++ b/docs/local-dev.md
@@ -55,8 +55,8 @@ DS_LOCAL_DATA_ROOT=/tmp/my-ds-local bun run src/local/cli.ts start --name defaul
 
 ## Programmatic API
 
-The published `@prisma/streams-local` package surface is built for both Bun and
-Node consumers.
+The published `@prisma/streams-local` package surface is built for Bun
+`>=1.2.0` and Node `>=22` consumers.
 
 ```ts
 import { startLocalDurableStreamsServer } from "@prisma/streams-local";
diff --git a/docs/overview.md b/docs/overview.md
index 9317a3c..8ebea23 100644
--- a/docs/overview.md
+++ b/docs/overview.md
@@ -70,8 +70,8 @@ See [security.md](./security.md) and [auth.md](./auth.md).
 
 ## Prerequisites
 
-- Bun `>=1.3.11`
-- Node.js `>=22` for local embedding and Node-based consumers
+- Bun `>=1.3.11` for the full self-hosted server and repository workflows
+- Bun `>=1.2.0` or Node.js `>=22` for the published `@prisma/streams-local` package
 
 ## Quick Start
 
@@ -116,8 +116,8 @@ console.log(server.exports.sqlite.path);
 await server.close();
 ```
 
-The published `@prisma/streams-local` surface is built to run on both Bun and
-Node. The full self-hosted server remains Bun-only.
+The published `@prisma/streams-local` surface is built to run on Bun `>=1.2.0`
+and Node `>=22`. The full self-hosted server remains Bun-only.
 
 The local embedded runtime always applies the built-in `1024 MB` auto-tune
 preset. That keeps the local package on the current control-plane and endpoint
diff --git a/docs/releasing.md b/docs/releasing.md
index 394684e..6341498 100644
--- a/docs/releasing.md
+++ b/docs/releasing.md
@@ -12,6 +12,14 @@ and other trusted local workflows.
 
 ## Release Checklist
 
+Release branch policy:
+
+- Always cut and publish releases from `main` only.
+- Do not run `release.yml` against feature branches or temporary release
+  branches.
+- Merge the release changes into `main` first, then dispatch the release
+  workflow from `main`.
+
 0. Ensure npm trusted publishing is configured for both packages:
 
 - `@prisma/streams-local`
@@ -46,7 +54,7 @@ These tests build the generated package directories, pack them, install them
 into temporary consumers, and verify:
 
 - Node end-to-end usage of `@prisma/streams-local`
-- Bun end-to-end usage of `@prisma/streams-local`, including the live `/touch/*` path
+- Bun end-to-end usage of `@prisma/streams-local` on Bun `1.2.x` and newer, including the live `/touch/*` path
 - stateful local-runtime reopen flows that must read `/_schema` and skip
   duplicate first-schema installs when the registry already matches
 - local package exposure of `GET /v1/server/_details` and `GET /v1/stream/{name}/_routing_keys`
@@ -81,10 +89,10 @@ npm publish --access public ./dist/npm/streams-local
 npm publish --access public ./dist/npm/streams-server
 ```
 
-Or use the repository release workflow after pushing to `main`:
+Or use the repository release workflow from `main` only:
 
 ```bash
-gh workflow run release.yml
+gh workflow run release.yml --ref main
 ```
 
 The GitHub workflow builds, validates, and publishes both packages with npm
@@ -113,6 +121,8 @@ For `@prisma/streams-local`, the build intentionally:
   each embed their own copy of the runtime
 - keeps the local runtime Bun-compatible even though the generated bundle
   targets the Node module surface
+- publishes a local-package Bun engine floor of `>=1.2.0` while keeping the
+  full server on the repository Bun floor
 - pins the embedded local runtime to the built-in `1024 MB` auto-tune preset so
   Prisma CLI gets a predictable cache and concurrency budget
 - keeps npm dependencies external instead of rebundling them into the local
@@ -133,7 +143,7 @@ The split gives you:
 
 ## Current Packaging Contract
 
-- `@prisma/streams-local` supports Bun and Node
+- `@prisma/streams-local` supports Bun `>=1.2.0` and Node `>=22`
 - `@prisma/streams-local/internal/daemon` is intentionally internal
 - `@prisma/streams-server` is Bun-only
 - the root repository package is still private and is not the publish target
diff --git a/package.json b/package.json
index 9c0be2f..faeab02 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "prisma-streams",
-  "version": "0.1.3",
+  "version": "0.1.4",
   "private": true,
   "description": "Prisma Streams is a Bun + TypeScript implementation of the Durable Streams HTTP protocol, with a local development server for Prisma CLI integration.",
   "repository": {
diff --git a/scripts/build-local-node.mjs b/scripts/build-local-node.mjs
index 46f1ebe..3f11770 100644
--- a/scripts/build-local-node.mjs
+++ b/scripts/build-local-node.mjs
@@ -2,6 +2,7 @@ import { cpSync, mkdirSync, readdirSync, readFileSync, rmSync, writeFileSync } f
 import { dirname, join, resolve } from "node:path";
 import { fileURLToPath } from "node:url";
 import { spawnSync } from "node:child_process";
+import { localPackageBunEngine } from "./package-contract.mjs";
 
 const __dirname = dirname(fileURLToPath(import.meta.url));
 const repoRoot = resolve(__dirname, "..");
@@ -36,8 +37,8 @@ function replaceInBuiltLocalFiles(replacements) {
 function writeDistReadme() {
   const readme = `# Prisma Streams Local Build
 
-This directory contains the generated Node-compatible package artifacts for the
-published \`@prisma/streams-local\` runtime.
+This directory contains the generated Node/Bun-compatible package artifacts for
+the published \`@prisma/streams-local\` runtime.
 
 ## What Local Streams Is
 
@@ -52,13 +53,18 @@ The embedded local runtime always applies the built-in \`1024 MB\` auto-tune
 preset, so Prisma CLI gets a predictable cache and concurrency budget and the
 same current HTTP surface, including \`GET /v1/server/_details\`.
 
+Published runtime floor:
+
+- Bun \`${localPackageBunEngine}\`
+- Node.js \`>=22\`
+
 ## Supported Package Surface
 
 - \`@prisma/streams-local\`
 - \`@prisma/streams-local/internal/daemon\` (internal Prisma CLI plumbing)
 
-The full self-hosted server remains Bun-only and is not part of this Node build
-surface.
+The full self-hosted server remains Bun-only and is not part of this local
+build surface.
 
 ## Integrating It
 
diff --git a/scripts/build-npm-packages.mjs b/scripts/build-npm-packages.mjs
index ee56c39..3343ed5 100644
--- a/scripts/build-npm-packages.mjs
+++ b/scripts/build-npm-packages.mjs
@@ -2,6 +2,7 @@ import { chmodSync, cpSync, mkdirSync, readFileSync, rmSync, writeFileSync } fro
 import { dirname, join, resolve } from "node:path";
 import { fileURLToPath } from "node:url";
 import { spawnSync } from "node:child_process";
+import { localPackageBunEngine } from "./package-contract.mjs";
 
 const __dirname = dirname(fileURLToPath(import.meta.url));
 const repoRoot = resolve(__dirname, "..");
@@ -104,7 +105,7 @@ function buildLocalPackage() {
     license: rootPackage.license,
     type: "module",
     engines: {
-      bun: rootPackage.engines.bun,
+      bun: localPackageBunEngine,
       node: rootPackage.engines.node,
     },
     publishConfig: {
diff --git a/scripts/package-contract.mjs b/scripts/package-contract.mjs
new file mode 100644
index 0000000..19641e2
--- /dev/null
+++ b/scripts/package-contract.mjs
@@ -0,0 +1 @@
+export const localPackageBunEngine = ">=1.2.0";
diff --git a/scripts/test-bun-local-package.mjs b/scripts/test-bun-local-package.mjs
index ef7263c..f68d65b 100644
--- a/scripts/test-bun-local-package.mjs
+++ b/scripts/test-bun-local-package.mjs
@@ -3,6 +3,7 @@ import { fileURLToPath } from "node:url";
 import { basename, dirname, join, resolve } from "node:path";
 import { tmpdir } from "node:os";
 import { spawnSync } from "node:child_process";
+import { localPackageBunEngine } from "./package-contract.mjs";
 
 const repoRoot = resolve(dirname(fileURLToPath(import.meta.url)), "..");
 const TABLE_KEY_POSTS = "8c646d3dd6bc68f4";
@@ -38,6 +39,9 @@ try {
   if ("@durable-streams/client" in (localPackageManifest.dependencies ?? {})) {
     throw new Error("@prisma/streams-local should not publish @durable-streams/client");
   }
+  if (localPackageManifest.engines?.bun !== localPackageBunEngine) {
+    throw new Error(`@prisma/streams-local should publish bun ${localPackageBunEngine}, got ${localPackageManifest.engines?.bun}`);
+  }
   const packOutput = run("npm", ["pack", "--pack-destination", packDir], localPackageDir);
   const tarballName = packOutput.split(/\r?\n/).filter(Boolean).at(-1);
   if (!tarballName) throw new Error("npm pack did not produce a tarball name");
diff --git a/scripts/test-node-local-package.mjs b/scripts/test-node-local-package.mjs
index 819927f..6be7ecd 100644
--- a/scripts/test-node-local-package.mjs
+++ b/scripts/test-node-local-package.mjs
@@ -3,6 +3,7 @@ import { fileURLToPath } from "node:url";
 import { basename, dirname, join, resolve } from "node:path";
 import { tmpdir } from "node:os";
 import { spawnSync } from "node:child_process";
+import { localPackageBunEngine } from "./package-contract.mjs";
 
 const repoRoot = resolve(dirname(fileURLToPath(import.meta.url)), "..");
 const TABLE_KEY_POSTS = "8c646d3dd6bc68f4";
@@ -38,6 +39,9 @@ try {
   if ("@durable-streams/client" in (localPackageManifest.dependencies ?? {})) {
     throw new Error("@prisma/streams-local should not publish @durable-streams/client");
   }
+  if (localPackageManifest.engines?.bun !== localPackageBunEngine) {
+    throw new Error(`@prisma/streams-local should publish bun ${localPackageBunEngine}, got ${localPackageManifest.engines?.bun}`);
+  }
   const packOutput = run("npm", ["pack", "--pack-destination", packDir], localPackageDir);
   const tarballName = packOutput.split(/\r?\n/).filter(Boolean).at(-1);
   if (!tarballName) throw new Error("npm pack did not produce a tarball name");
diff --git a/src/bootstrap.ts b/src/bootstrap.ts
index c305081..377fffc 100644
--- a/src/bootstrap.ts
+++ b/src/bootstrap.ts
@@ -1,9 +1,9 @@
 import { mkdirSync, rmSync } from "node:fs";
 import { dirname } from "node:path";
-import { zstdDecompressSync } from "node:zlib";
 import type { Config } from "./config";
 import { SqliteDurableStore } from "./db/db";
 import type { ObjectStore } from "./objectstore/interface";
+import { zstdDecompressSync } from "./util/zstd";
 import { localSegmentPath, schemaObjectKey, segmentObjectKey, streamHash16Hex } from "./util/stream_paths";
 import { retry } from "./util/retry";
 import { dsError } from "./util/ds_error.ts";
diff --git a/src/manifest.ts b/src/manifest.ts
index d755ce2..cdfd58f 100644
--- a/src/manifest.ts
+++ b/src/manifest.ts
@@ -1,4 +1,3 @@
-import { zstdCompressSync } from "node:zlib";
 import { Result } from "better-result";
 import type {
   IndexRunRow,
@@ -13,6 +12,7 @@ import type {
   StreamRow,
 } from "./db/db";
 import { encodeOffsetResult } from "./offset";
+import { zstdCompressSync } from "./util/zstd";
 import { dsError } from "./util/ds_error.ts";
 
 function b64(bytes: Uint8Array): string {
diff --git a/src/profiles/metrics/block_format.ts b/src/profiles/metrics/block_format.ts
index 8e8f81c..bddb9c2 100644
--- a/src/profiles/metrics/block_format.ts
+++ b/src/profiles/metrics/block_format.ts
@@ -1,6 +1,6 @@
 import { Result } from "better-result";
-import { zstdCompressSync, zstdDecompressSync } from "node:zlib";
 import { BinaryCursor, BinaryPayloadError, BinaryWriter, readI64 } from "../../search/binary/codec";
+import { zstdCompressSync, zstdDecompressSync } from "../../util/zstd";
 import type { MetricsBlockRecord } from "./normalize";
 
 export type MetricsBlockSectionInput = {
diff --git a/src/search/agg_format.ts b/src/search/agg_format.ts
index 15cffaf..b2797de 100644
--- a/src/search/agg_format.ts
+++ b/src/search/agg_format.ts
@@ -1,8 +1,8 @@
 import { Result } from "better-result";
-import { zstdCompressSync, zstdDecompressSync } from "node:zlib";
 import { BinaryCursor, BinaryPayloadError, BinaryWriter, concatBytes, readF64, readI64, readU16, readU32 } from "./binary/codec";
 import { RestartStringTableView, encodeRestartStringTable } from "./binary/restart_strings";
 import { readUVarint, readZigZagVarint, writeUVarint, writeZigZagVarint } from "./binary/varint";
+import { zstdCompressSync, zstdDecompressSync } from "../util/zstd";
 import type { SearchCompanionPlan, SearchCompanionPlanRollup } from "./companion_plan";
 
 export type AggSummaryState = {
diff --git a/src/segment/format.ts b/src/segment/format.ts
index a2c3d2c..942b550 100644
--- a/src/segment/format.ts
+++ b/src/segment/format.ts
@@ -1,9 +1,9 @@
 import { Result } from "better-result";
-import { zstdCompressSync, zstdDecompressSync } from "node:zlib";
 import { Bloom256 } from "../util/bloom256";
 import { crc32c } from "../util/crc32c";
 import { concatBytes, readU32BE, readU64BE, writeU32BE, writeU64BE } from "../util/endian";
 import { dsError } from "../util/ds_error.ts";
+import { zstdCompressSync, zstdDecompressSync } from "../util/zstd";
 
 export type SegmentRecord = {
   appendNs: bigint;
diff --git a/src/util/zstd.ts b/src/util/zstd.ts
new file mode 100644
index 0000000..5bd405b
--- /dev/null
+++ b/src/util/zstd.ts
@@ -0,0 +1,24 @@
+import * as zlib from "node:zlib";
+import { dsError } from "./ds_error.ts";
+
+type ZstdOperation = (bytes: Uint8Array) => Uint8Array | Buffer;
+
+function getZstdOperation(name: "zstdCompressSync" | "zstdDecompressSync") {
+  const operation = (zlib as Record<string, unknown>)[name];
+
+  if (typeof operation !== "function") {
+    throw dsError(
+      `${name} is not available in this runtime. Prisma Streams local requires node:zlib zstd support.`,
+    );
+  }
+
+  return operation as ZstdOperation;
+}
+
+export function zstdCompressSync(bytes: Uint8Array) {
+  return getZstdOperation("zstdCompressSync")(bytes);
+}
+
+export function zstdDecompressSync(bytes: Uint8Array) {
+  return getZstdOperation("zstdDecompressSync")(bytes);
+}
diff --git a/test/live_stream2_read_perf.test.ts b/test/live_stream2_read_perf.test.ts
index 0c1d179..d52e854 100644
--- a/test/live_stream2_read_perf.test.ts
+++ b/test/live_stream2_read_perf.test.ts
@@ -87,7 +87,7 @@ describe("live stream-2 read perf fixtures", () => {
       expect(bodyBytes).toBeGreaterThan(600_000);
       expect(elapsedMs).toBeLessThan(100);
     });
-  });
+  }, 15_000);
 
   test("wal-tail read stays below 100ms on warm live fixture data", async () => {
     await withFixtureApp(async (app) => {
@@ -96,5 +96,5 @@ describe("live stream-2 read perf fixtures", () => {
       expect(bodyBytes).toBeGreaterThan(600_000);
       expect(elapsedMs).toBeLessThan(100);
     });
-  });
+  }, 15_000);
 });