diff --git a/.pnp.js b/.pnp.js
index caf080db..c013dda2 100755
--- a/.pnp.js
+++ b/.pnp.js
@@ -3398,7 +3398,6 @@ function $$SETUP_STATE(hydrateRuntimeState, basePath) {
           "packageDependencies": [
             ["@cosmjs/cosmwasm-stargate", "workspace:packages/cosmwasm-stargate"],
             ["@cosmjs/amino", "workspace:packages/amino"],
-            ["@cosmjs/cosmwasm-launchpad", "workspace:packages/cosmwasm-launchpad"],
             ["@cosmjs/crypto", "workspace:packages/crypto"],
             ["@cosmjs/encoding", "workspace:packages/encoding"],
             ["@cosmjs/math", "workspace:packages/math"],
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 62517f86..bfcad33c 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -17,6 +17,11 @@ and this project adheres to
   available under `tendermint33`.
 - @cosmjs/proto-signing and @cosmjs/stargate: Create a Stargate-ready
   `parseCoins` that replaces the `parseCoins` re-export from `@cosmjs/amino`.
+- @cosmjs/cosmwasm-stargate: Export `isValidBuilder`, which is a clone of
+  `isValidBuilder` from @cosmjs/cosmwasm-launchpad.
+- @cosmjs/cosmwasm-stargate: Copy symbols `Code`, `CodeDetails`, `Contract`,
+  `ContractCodeHistoryEntry` and `JsonObject` from @cosmjs/cosmwasm-launchpad
+  and remove dependency on @cosmjs/cosmwasm-launchpad.
 
 ### Changed
 
diff --git a/packages/cosmwasm-launchpad/src/cosmwasmclient.ts b/packages/cosmwasm-launchpad/src/cosmwasmclient.ts
index 1f7324e1..3915971b 100644
--- a/packages/cosmwasm-launchpad/src/cosmwasmclient.ts
+++ b/packages/cosmwasm-launchpad/src/cosmwasmclient.ts
@@ -95,7 +95,7 @@ export interface Code {
 }
 
 export interface CodeDetails extends Code {
-  /** The original wasm bytes */
+  /** The original Wasm bytes */
   readonly data: Uint8Array;
 }
 
diff --git a/packages/cosmwasm-stargate/package.json b/packages/cosmwasm-stargate/package.json
index 8e21300e..3333a1b4 100644
--- a/packages/cosmwasm-stargate/package.json
+++ b/packages/cosmwasm-stargate/package.json
@@ -38,7 +38,6 @@
   },
   "dependencies": {
     "@cosmjs/amino": "workspace:packages/amino",
-    "@cosmjs/cosmwasm-launchpad": "workspace:packages/cosmwasm-launchpad",
     "@cosmjs/crypto": "workspace:packages/crypto",
     "@cosmjs/encoding": "workspace:packages/encoding",
     "@cosmjs/math": "workspace:packages/math",
diff --git a/packages/cosmwasm-stargate/src/builder.spec.ts b/packages/cosmwasm-stargate/src/builder.spec.ts
new file mode 100644
index 00000000..20926f4c
--- /dev/null
+++ b/packages/cosmwasm-stargate/src/builder.spec.ts
@@ -0,0 +1,63 @@
+import { isValidBuilder } from "./builder";
+
+describe("builder", () => {
+  describe("isValidBuilder", () => {
+    // Valid cases
+
+    it("returns true for simple examples", () => {
+      expect(isValidBuilder("myorg/super-optimizer:0.1.2")).toEqual(true);
+      expect(isValidBuilder("myorg/super-optimizer:42")).toEqual(true);
+    });
+
+    it("supports images with multi level names", () => {
+      expect(isValidBuilder("myorg/department-x/office-y/technology-z/super-optimizer:0.1.2")).toEqual(true);
+    });
+
+    it("returns true for tags with lower and upper chars", () => {
+      expect(isValidBuilder("myorg/super-optimizer:0.1.2-alpha")).toEqual(true);
+      expect(isValidBuilder("myorg/super-optimizer:0.1.2-Alpha")).toEqual(true);
+    });
+
+    // Invalid cases
+
+    it("returns false for missing or empty tag", () => {
+      expect(isValidBuilder("myorg/super-optimizer")).toEqual(false);
+      expect(isValidBuilder("myorg/super-optimizer:")).toEqual(false);
+    });
+
+    it("returns false for name components starting or ending with a separator", () => {
+      expect(isValidBuilder(".myorg/super-optimizer:42")).toEqual(false);
+      expect(isValidBuilder("-myorg/super-optimizer:42")).toEqual(false);
+      expect(isValidBuilder("_myorg/super-optimizer:42")).toEqual(false);
+      expect(isValidBuilder("myorg./super-optimizer:42")).toEqual(false);
+      expect(isValidBuilder("myorg-/super-optimizer:42")).toEqual(false);
+      expect(isValidBuilder("myorg_/super-optimizer:42")).toEqual(false);
+      expect(isValidBuilder("myorg/.super-optimizer:42")).toEqual(false);
+      expect(isValidBuilder("myorg/-super-optimizer:42")).toEqual(false);
+      expect(isValidBuilder("myorg/_super-optimizer:42")).toEqual(false);
+      expect(isValidBuilder("myorg/super-optimizer.:42")).toEqual(false);
+      expect(isValidBuilder("myorg/super-optimizer-:42")).toEqual(false);
+      expect(isValidBuilder("myorg/super-optimizer_:42")).toEqual(false);
+    });
+
+    it("returns false for upper case character in name component", () => {
+      expect(isValidBuilder("mYorg/super-optimizer:42")).toEqual(false);
+      expect(isValidBuilder("myorg/super-Optimizer:42")).toEqual(false);
+    });
+
+    it("returns false for long images", () => {
+      expect(
+        isValidBuilder(
+          "myorgisnicenicenicenicenicenicenicenicenicenicenicenicenicenicenicenicenicenicenicenicenicenicenicenicenicenice/super-optimizer:42",
+        ),
+      ).toEqual(false);
+    });
+
+    it("returns false for images with no organization", () => {
+      // Those are valid dockerhub images from https://hub.docker.com/_/ubuntu and https://hub.docker.com/_/rust
+      // but not valid in the context of CosmWasm Verify
+      expect(isValidBuilder("ubuntu:xenial-20200212")).toEqual(false);
+      expect(isValidBuilder("rust:1.40.0")).toEqual(false);
+    });
+  });
+});
diff --git a/packages/cosmwasm-stargate/src/builder.ts b/packages/cosmwasm-stargate/src/builder.ts
new file mode 100644
index 00000000..31a790c7
--- /dev/null
+++ b/packages/cosmwasm-stargate/src/builder.ts
@@ -0,0 +1,20 @@
+// A docker image regexp. We remove support for non-standard registries for simplicity.
+// https://docs.docker.com/engine/reference/commandline/tag/#extended-description
+//
+// An image name is made up of slash-separated name components (optionally prefixed by a registry hostname).
+// Name components may contain lowercase characters, digits and separators.
+// A separator is defined as a period, one or two underscores, or one or more dashes. A name component may not start or end with a separator.
+//
+// A tag name must be valid ASCII and may contain lowercase and uppercase letters, digits, underscores, periods and dashes.
+// A tag name may not start with a period or a dash and may contain a maximum of 128 characters.
+const dockerImagePattern = new RegExp(
+  "^[a-z0-9][a-z0-9._-]*[a-z0-9](/[a-z0-9][a-z0-9._-]*[a-z0-9])+:[a-zA-Z0-9_][a-zA-Z0-9_.-]{0,127}$",
+);
+
+/** Max length in bytes/characters (regexp enforces all ASCII, even if that is not required by the standard) */
+const builderMaxLength = 128;
+
+export function isValidBuilder(builder: string): boolean {
+  if (builder.length > builderMaxLength) return false;
+  return !!builder.match(dockerImagePattern);
+}
diff --git a/packages/cosmwasm-stargate/src/cosmwasmclient.spec.ts b/packages/cosmwasm-stargate/src/cosmwasmclient.spec.ts
index 3092ded5..83647705 100644
--- a/packages/cosmwasm-stargate/src/cosmwasmclient.spec.ts
+++ b/packages/cosmwasm-stargate/src/cosmwasmclient.spec.ts
@@ -1,5 +1,4 @@
 /* eslint-disable @typescript-eslint/naming-convention */
-import { Code } from "@cosmjs/cosmwasm-launchpad";
 import { sha256 } from "@cosmjs/crypto";
 import { fromAscii, fromBase64, fromHex, toAscii } from "@cosmjs/encoding";
 import { Int53 } from "@cosmjs/math";
@@ -16,7 +15,7 @@ import { assert, sleep } from "@cosmjs/utils";
 import { TxRaw } from "cosmjs-types/cosmos/tx/v1beta1/tx";
 import { ReadonlyDate } from "readonly-date";
 
-import { CosmWasmClient, PrivateCosmWasmClient } from "./cosmwasmclient";
+import { Code, CosmWasmClient, PrivateCosmWasmClient } from "./cosmwasmclient";
 import { SigningCosmWasmClient } from "./signingcosmwasmclient";
 import {
   alice,
diff --git a/packages/cosmwasm-stargate/src/cosmwasmclient.ts b/packages/cosmwasm-stargate/src/cosmwasmclient.ts
index 147ead52..c0529b86 100644
--- a/packages/cosmwasm-stargate/src/cosmwasmclient.ts
+++ b/packages/cosmwasm-stargate/src/cosmwasmclient.ts
@@ -1,11 +1,4 @@
 /* eslint-disable @typescript-eslint/naming-convention */
-import {
-  Code,
-  CodeDetails,
-  Contract,
-  ContractCodeHistoryEntry,
-  JsonObject,
-} from "@cosmjs/cosmwasm-launchpad";
 import { fromAscii, toHex } from "@cosmjs/encoding";
 import { Uint53 } from "@cosmjs/math";
 import {
@@ -33,18 +26,56 @@ import { assert, sleep } from "@cosmjs/utils";
 import { CodeInfoResponse } from "cosmjs-types/cosmwasm/wasm/v1beta1/query";
 import { ContractCodeHistoryOperationType } from "cosmjs-types/cosmwasm/wasm/v1beta1/types";
 
-import { setupWasmExtension, WasmExtension } from "./queries";
+import { JsonObject, setupWasmExtension, WasmExtension } from "./queries";
 
-// Those types can be copied over to allow them to evolve independently of @cosmjs/cosmwasm-launchpad.
-// For now just re-export them such that they can be imported via @cosmjs/cosmwasm-stargate.
+// Re-exports that belong to public CosmWasmClient interfaces
 export {
-  Code, // returned by CosmWasmClient.getCode
-  CodeDetails, // returned by CosmWasmClient.getCodeDetails
-  Contract, // returned by CosmWasmClient.getContract
-  ContractCodeHistoryEntry, // returned by CosmWasmClient.getContractCodeHistory
   JsonObject, // returned by CosmWasmClient.queryContractSmart
 };
 
+export interface Code {
+  readonly id: number;
+  /** Bech32 account address */
+  readonly creator: string;
+  /** Hex-encoded sha256 hash of the code stored here */
+  readonly checksum: string;
+  /**
+   * An URL to a .tar.gz archive of the source code of the contract, which can be used to reproducibly build the Wasm bytecode.
+   *
+   * @see https://github.com/CosmWasm/cosmwasm-verify
+   */
+  readonly source?: string;
+  /**
+   * A docker image (including version) to reproducibly build the Wasm bytecode from the source code.
+   *
+   * @example ```cosmwasm/rust-optimizer:0.8.0```
+   * @see https://github.com/CosmWasm/cosmwasm-verify
+   */
+  readonly builder?: string;
+}
+
+export interface CodeDetails extends Code {
+  /** The original Wasm bytes */
+  readonly data: Uint8Array;
+}
+
+export interface Contract {
+  readonly address: string;
+  readonly codeId: number;
+  /** Bech32 account address */
+  readonly creator: string;
+  /** Bech32-encoded admin address */
+  readonly admin: string | undefined;
+  readonly label: string;
+}
+
+export interface ContractCodeHistoryEntry {
+  /** The source of this history entry */
+  readonly operation: "Genesis" | "Init" | "Migrate";
+  readonly codeId: number;
+  readonly msg: Record<string, unknown>;
+}
+
 /** Use for testing only */
 export interface PrivateCosmWasmClient {
   readonly tmClient: Tendermint34Client | undefined;
diff --git a/packages/cosmwasm-stargate/src/index.ts b/packages/cosmwasm-stargate/src/index.ts
index e90bbc57..c02bdae8 100644
--- a/packages/cosmwasm-stargate/src/index.ts
+++ b/packages/cosmwasm-stargate/src/index.ts
@@ -1,4 +1,5 @@
 export { cosmWasmTypes } from "./aminotypes";
+export { isValidBuilder } from "./builder";
 export {
   Code,
   CodeDetails,
diff --git a/packages/cosmwasm-stargate/src/queries/index.ts b/packages/cosmwasm-stargate/src/queries/index.ts
index c0692523..c33027c9 100644
--- a/packages/cosmwasm-stargate/src/queries/index.ts
+++ b/packages/cosmwasm-stargate/src/queries/index.ts
@@ -1 +1 @@
-export { setupWasmExtension, WasmExtension } from "./wasm";
+export { setupWasmExtension, JsonObject, WasmExtension } from "./wasm";
diff --git a/packages/cosmwasm-stargate/src/queries/wasm.ts b/packages/cosmwasm-stargate/src/queries/wasm.ts
index 579ab1d0..229a0cb8 100644
--- a/packages/cosmwasm-stargate/src/queries/wasm.ts
+++ b/packages/cosmwasm-stargate/src/queries/wasm.ts
@@ -1,5 +1,4 @@
 /* eslint-disable @typescript-eslint/naming-convention */
-import { JsonObject } from "@cosmjs/cosmwasm-launchpad";
 import { fromUtf8, toAscii } from "@cosmjs/encoding";
 import { createPagination, createProtobufRpcClient, QueryClient } from "@cosmjs/stargate";
 import {
@@ -14,6 +13,14 @@ import {
 } from "cosmjs-types/cosmwasm/wasm/v1beta1/query";
 import Long from "long";
 
+/**
+ * An object containing a parsed JSON document. The result of JSON.parse().
+ * This doesn't provide any type safety over `any` but expresses intent in the code.
+ *
+ * This type is returned by `queryContractSmart`.
+ */
+export type JsonObject = any;
+
 export interface WasmExtension {
   readonly wasm: {
     readonly listCodeInfo: (paginationKey?: Uint8Array) => Promise<QueryCodesResponse>;
diff --git a/packages/cosmwasm-stargate/src/signingcosmwasmclient.ts b/packages/cosmwasm-stargate/src/signingcosmwasmclient.ts
index c95632b3..f02a4f84 100644
--- a/packages/cosmwasm-stargate/src/signingcosmwasmclient.ts
+++ b/packages/cosmwasm-stargate/src/signingcosmwasmclient.ts
@@ -1,6 +1,5 @@
 /* eslint-disable @typescript-eslint/naming-convention */
 import { encodeSecp256k1Pubkey, makeSignDoc as makeSignDocAmino } from "@cosmjs/amino";
-import { isValidBuilder } from "@cosmjs/cosmwasm-launchpad";
 import { sha256 } from "@cosmjs/crypto";
 import { fromBase64, toHex, toUtf8 } from "@cosmjs/encoding";
 import { Int53, Uint53 } from "@cosmjs/math";
@@ -47,6 +46,7 @@ import Long from "long";
 import pako from "pako";
 
 import { cosmWasmTypes } from "./aminotypes";
+import { isValidBuilder } from "./builder";
 import { CosmWasmClient } from "./cosmwasmclient";
 import {
   MsgClearAdminEncodeObject,
@@ -57,9 +57,9 @@ import {
   MsgUpdateAdminEncodeObject,
 } from "./encodeobjects";
 
-function prepareBuilder(builder: string | undefined): string {
-  if (builder === undefined) {
-    return ""; // normalization needed by backend
+function prepareBuilder(builder: string | undefined): string | undefined {
+  if (!builder) {
+    return undefined;
   } else {
     if (!isValidBuilder(builder)) throw new Error("The builder (Docker Hub image with tag) is not valid");
     return builder;
diff --git a/yarn.lock b/yarn.lock
index a701535e..200e87d1 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -446,7 +446,6 @@ __metadata:
   resolution: "@cosmjs/cosmwasm-stargate@workspace:packages/cosmwasm-stargate"
   dependencies:
     "@cosmjs/amino": "workspace:packages/amino"
-    "@cosmjs/cosmwasm-launchpad": "workspace:packages/cosmwasm-launchpad"
     "@cosmjs/crypto": "workspace:packages/crypto"
     "@cosmjs/encoding": "workspace:packages/encoding"
     "@cosmjs/math": "workspace:packages/math"