refactor: move brother_node development artifact to dev/test-nodes subdirectory

Development Artifact Cleanup:
✅ BROTHER_NODE REORGANIZATION: Moved development test node to appropriate location
- dev/test-nodes/brother_node/: Moved from root directory for better organization
- Contains development configuration, test logs, and test chain data
- No impact on production systems - purely development/testing artifact

✅ DEVELOPMENT ARTIFACTS IDENTIFIED:
- Chain ID: aitbc-brother-chain (test/development chain)
- Ports: 8010 (P2P) and 8011 (RPC) - different from production
- Environment: .env file with test configuration
- Logs: rpc.log and node.log from development testing session (March 15, 2026)

✅ ROOT DIRECTORY CLEANUP: Removed development clutter from production directory
- brother_node/ moved to dev/test-nodes/brother_node/
- Root directory now contains only production-ready components
- Development artifacts properly organized in dev/ subdirectory

DIRECTORY STRUCTURE IMPROVEMENT:
📁 dev/test-nodes/: Development and testing node configurations
🏗️ Root Directory: Clean production structure with only essential components
🧪 Development Isolation: Test environments separated from production

BENEFITS:
✅ Clean Production Directory: No development artifacts in root
✅ Better Organization: Development nodes grouped in dev/ subdirectory
✅ Clear Separation: Production vs development environments clearly distinguished
✅ Maintainability: Easier to identify and manage development components

RESULT: Successfully moved brother_node development artifact to dev/test-nodes/ subdirectory, cleaning up the root directory while preserving development testing environment for future use.

dev/env/node_modules/ethers/src.ts/hash/authorization.ts

@@ -0,0 +1,38 @@
+import { getAddress } from "../address/index.js";
+import { keccak256 } from "../crypto/index.js";
+import { recoverAddress } from "../transaction/index.js";
+import {
+    assertArgument, concat, encodeRlp, toBeArray
+} from "../utils/index.js";
+
+import type { Addressable } from "../address/index.js";
+import type { SignatureLike } from "../crypto/index.js";
+import type { BigNumberish, Numeric } from "../utils/index.js";
+
+export interface AuthorizationRequest {
+    address: string | Addressable;
+    nonce?: Numeric;
+    chainId?: BigNumberish;
+}
+
+/**
+ *  Computes the [[link-eip-7702]] authorization digest to sign.
+ */
+export function hashAuthorization(auth: AuthorizationRequest): string {
+    assertArgument(typeof(auth.address) === "string", "invalid address for hashAuthorization", "auth.address", auth);
+    return keccak256(concat([
+        "0x05", encodeRlp([
+            (auth.chainId != null) ? toBeArray(auth.chainId): "0x",
+            getAddress(auth.address),
+            (auth.nonce != null) ? toBeArray(auth.nonce): "0x",
+        ])
+    ]));
+}
+
+/**
+ *  Return the address of the private key that produced
+ *  the signature %%sig%% during signing for %%message%%.
+ */
+export function verifyAuthorization(auth: AuthorizationRequest, sig: SignatureLike): string {
+    return recoverAddress(hashAuthorization(auth), sig);
+}

dev/env/node_modules/ethers/src.ts/hash/id.ts

@@ -0,0 +1,17 @@
+import { keccak256 } from "../crypto/index.js";
+import { toUtf8Bytes } from "../utils/index.js";
+
+/**
+ *  A simple hashing function which operates on UTF-8 strings to
+ *  compute an 32-byte identifier.
+ *
+ *  This simply computes the [UTF-8 bytes](toUtf8Bytes) and computes
+ *  the [[keccak256]].
+ *
+ *  @example:
+ *    id("hello world")
+ *    //_result:
+ */
+export function id(value: string): string {
+    return keccak256(toUtf8Bytes(value));
+}

dev/env/node_modules/ethers/src.ts/hash/index.ts

@@ -0,0 +1,18 @@
+/**
+ *  Utilities for common tasks involving hashing. Also see
+ *  [cryptographic hashing](about-crypto-hashing).
+ *
+ *  @_section: api/hashing:Hashing Utilities  [about-hashing]
+ */
+
+export { hashAuthorization, verifyAuthorization } from "./authorization.js";
+export { id } from "./id.js"
+export { ensNormalize, isValidName, namehash, dnsEncode } from "./namehash.js";
+export { hashMessage, verifyMessage } from "./message.js";
+export {
+    solidityPacked, solidityPackedKeccak256, solidityPackedSha256
+} from "./solidity.js";
+export { TypedDataEncoder, verifyTypedData } from "./typed-data.js";
+
+export type { AuthorizationRequest } from "./authorization.js";
+export type { TypedDataDomain, TypedDataField } from "./typed-data.js";

dev/env/node_modules/ethers/src.ts/hash/message.ts

@@ -0,0 +1,51 @@
+import { keccak256 } from "../crypto/index.js";
+import { MessagePrefix } from "../constants/index.js";
+import { recoverAddress } from "../transaction/index.js";
+import { concat, toUtf8Bytes } from "../utils/index.js";
+
+import type { SignatureLike } from "../crypto/index.js";
+/**
+ *  Computes the [[link-eip-191]] personal-sign message digest to sign.
+ *
+ *  This prefixes the message with [[MessagePrefix]] and the decimal length
+ *  of %%message%% and computes the [[keccak256]] digest.
+ *
+ *  If %%message%% is a string, it is converted to its UTF-8 bytes
+ *  first. To compute the digest of a [[DataHexString]], it must be converted
+ *  to [bytes](getBytes).
+ *
+ *  @example:
+ *    hashMessage("Hello World")
+ *    //_result:
+ *
+ *    // Hashes the SIX (6) string characters, i.e.
+ *    // [ "0", "x", "4", "2", "4", "3" ]
+ *    hashMessage("0x4243")
+ *    //_result:
+ *
+ *    // Hashes the TWO (2) bytes [ 0x42, 0x43 ]...
+ *    hashMessage(getBytes("0x4243"))
+ *    //_result:
+ *
+ *    // ...which is equal to using data
+ *    hashMessage(new Uint8Array([ 0x42, 0x43 ]))
+ *    //_result:
+ *
+ */
+export function hashMessage(message: Uint8Array | string): string {
+    if (typeof(message) === "string") { message = toUtf8Bytes(message); }
+    return keccak256(concat([
+        toUtf8Bytes(MessagePrefix),
+        toUtf8Bytes(String(message.length)),
+        message
+    ]));
+}
+
+/**
+ *  Return the address of the private key that produced
+ *  the signature %%sig%% during signing for %%message%%.
+ */
+export function verifyMessage(message: Uint8Array | string, sig: SignatureLike): string {
+    const digest = hashMessage(message);
+    return recoverAddress(digest, sig);
+}

dev/env/node_modules/ethers/src.ts/hash/namehash.ts

@@ -0,0 +1,101 @@
+
+import { keccak256 } from "../crypto/index.js";
+import {
+    concat, hexlify, assertArgument, toUtf8Bytes
+} from "../utils/index.js";
+
+
+import { ens_normalize } from "@adraffy/ens-normalize";
+
+const Zeros = new Uint8Array(32);
+Zeros.fill(0);
+
+function checkComponent(comp: Uint8Array): Uint8Array {
+    assertArgument(comp.length !== 0, "invalid ENS name; empty component", "comp", comp)
+    return comp;
+}
+
+function ensNameSplit(name: string): Array<Uint8Array> {
+    const bytes = toUtf8Bytes(ensNormalize(name));
+    const comps: Array<Uint8Array> = [ ];
+
+    if (name.length === 0) { return comps; }
+
+    let last = 0;
+    for (let i = 0; i < bytes.length; i++) {
+        const d = bytes[i];
+
+        // A separator (i.e. "."); copy this component
+        if (d === 0x2e) {
+            comps.push(checkComponent(bytes.slice(last, i)));
+            last = i + 1;
+        }
+    }
+
+    // There was a stray separator at the end of the name
+    assertArgument(last < bytes.length, "invalid ENS name; empty component", "name", name);
+
+    comps.push(checkComponent(bytes.slice(last)));
+    return comps;
+}
+
+/**
+ *  Returns the ENS %%name%% normalized.
+ */
+export function ensNormalize(name: string): string {
+    try {
+        if (name.length === 0) { throw new Error("empty label"); }
+        return ens_normalize(name);
+    } catch (error: any) {
+        assertArgument(false, `invalid ENS name (${ error.message })`, "name", name);
+    }
+}
+
+/**
+ *  Returns ``true`` if %%name%% is a valid ENS name.
+ */
+export function isValidName(name: string): name is string {
+    try {
+        return (ensNameSplit(name).length !== 0);
+    } catch (error) { }
+    return false;
+}
+
+/**
+ *  Returns the [[link-namehash]] for %%name%%.
+ */
+export function namehash(name: string): string {
+    assertArgument(typeof(name) === "string", "invalid ENS name; not a string", "name", name);
+
+    assertArgument(name.length, `invalid ENS name (empty label)`, "name", name);
+
+    let result: string | Uint8Array = Zeros;
+
+    const comps = ensNameSplit(name);
+    while (comps.length) {
+        result = keccak256(concat([ result, keccak256(<Uint8Array>(comps.pop()))] ));
+    }
+
+    return hexlify(result);
+}
+
+/**
+ *  Returns the DNS encoded %%name%%.
+ *
+ *  This is used for various parts of ENS name resolution, such
+ *  as the wildcard resolution.
+ */
+export function dnsEncode(name: string, _maxLength?: number): string {
+    const length = (_maxLength != null) ? _maxLength: 63;
+
+    assertArgument(length <= 255, "DNS encoded label cannot exceed 255", "length", length);
+
+    return hexlify(concat(ensNameSplit(name).map((comp) => {
+        assertArgument(comp.length <= length, `label ${ JSON.stringify(name) } exceeds ${ length } bytes`, "name", name);
+
+        const bytes = new Uint8Array(comp.length + 1);
+        bytes.set(comp, 1);
+        bytes[0] = bytes.length - 1;
+        return bytes;
+    }))) + "00";
+}

dev/env/node_modules/ethers/src.ts/hash/solidity.ts

@@ -0,0 +1,117 @@
+import { getAddress } from "../address/index.js";
+import {
+    keccak256 as _keccak256, sha256 as _sha256
+} from "../crypto/index.js";
+import {
+    concat, dataLength, getBytes, hexlify, toBeArray, toTwos, toUtf8Bytes, zeroPadBytes, zeroPadValue,
+    assertArgument
+} from "../utils/index.js";
+
+
+const regexBytes = new RegExp("^bytes([0-9]+)$");
+const regexNumber = new RegExp("^(u?int)([0-9]*)$");
+const regexArray = new RegExp("^(.*)\\[([0-9]*)\\]$");
+
+
+function _pack(type: string, value: any, isArray?: boolean): Uint8Array {
+    switch(type) {
+        case "address":
+            if (isArray) { return getBytes(zeroPadValue(value, 32)); }
+            return getBytes(getAddress(value));
+        case "string":
+            return toUtf8Bytes(value);
+        case "bytes":
+            return getBytes(value);
+        case "bool":
+            value = (!!value ? "0x01": "0x00");
+            if (isArray) { return getBytes(zeroPadValue(value, 32)); }
+            return getBytes(value);
+    }
+
+    let match =  type.match(regexNumber);
+    if (match) {
+        let signed = (match[1] === "int");
+        let size = parseInt(match[2] || "256")
+
+        assertArgument((!match[2] || match[2] === String(size)) && (size % 8 === 0) && size !== 0 && size <= 256, "invalid number type", "type", type);
+
+        if (isArray) { size = 256; }
+
+        if (signed) { value = toTwos(value, size); }
+
+        return getBytes(zeroPadValue(toBeArray(value), size / 8));
+    }
+
+    match = type.match(regexBytes);
+    if (match) {
+        const size = parseInt(match[1]);
+
+        assertArgument(String(size) === match[1] && size !== 0 && size <= 32, "invalid bytes type", "type", type);
+        assertArgument(dataLength(value) === size, `invalid value for ${ type }`, "value", value);
+
+        if (isArray) { return getBytes(zeroPadBytes(value, 32)); }
+        return value;
+    }
+
+    match = type.match(regexArray);
+    if (match && Array.isArray(value)) {
+        const baseType = match[1];
+        const count = parseInt(match[2] || String(value.length));
+        assertArgument(count === value.length, `invalid array length for ${ type }`, "value", value);
+
+        const result: Array<Uint8Array> = [];
+        value.forEach(function(value) {
+            result.push(_pack(baseType, value, true));
+        });
+        return getBytes(concat(result));
+    }
+
+    assertArgument(false, "invalid type", "type", type)
+}
+
+// @TODO: Array Enum
+
+/**
+ *   Computes the [[link-solc-packed]] representation of %%values%%
+ *   respectively to their %%types%%.
+ *
+ *   @example:
+ *       addr = "0x8ba1f109551bd432803012645ac136ddd64dba72"
+ *       solidityPacked([ "address", "uint" ], [ addr, 45 ]);
+ *       //_result:
+ */
+export function solidityPacked(types: ReadonlyArray<string>, values: ReadonlyArray<any>): string {
+    assertArgument(types.length === values.length, "wrong number of values; expected ${ types.length }", "values", values);
+
+    const tight: Array<Uint8Array> = [];
+    types.forEach(function(type, index) {
+        tight.push(_pack(type, values[index]));
+    });
+    return hexlify(concat(tight));
+}
+
+/**
+ *   Computes the [[link-solc-packed]] [[keccak256]] hash of %%values%%
+ *   respectively to their %%types%%.
+ *
+ *   @example:
+ *       addr = "0x8ba1f109551bd432803012645ac136ddd64dba72"
+ *       solidityPackedKeccak256([ "address", "uint" ], [ addr, 45 ]);
+ *       //_result:
+ */
+export function solidityPackedKeccak256(types: ReadonlyArray<string>, values: ReadonlyArray<any>): string {
+    return _keccak256(solidityPacked(types, values));
+}
+
+/**
+ *   Computes the [[link-solc-packed]] [[sha256]] hash of %%values%%
+ *   respectively to their %%types%%.
+ *
+ *   @example:
+ *       addr = "0x8ba1f109551bd432803012645ac136ddd64dba72"
+ *       solidityPackedSha256([ "address", "uint" ], [ addr, 45 ]);
+ *       //_result:
+ */
+export function solidityPackedSha256(types: ReadonlyArray<string>, values: ReadonlyArray<any>): string {
+    return _sha256(solidityPacked(types, values));
+}

dev/env/node_modules/ethers/src.ts/hash/typed-data.ts

@@ -0,0 +1,658 @@
+//import { TypedDataDomain, TypedDataField } from "@ethersproject/providerabstract-signer";
+import { getAddress } from "../address/index.js";
+import { keccak256 } from "../crypto/index.js";
+import { recoverAddress } from "../transaction/index.js";
+import {
+    concat, defineProperties, getBigInt, getBytes, hexlify, isHexString, mask, toBeHex, toQuantity, toTwos, zeroPadValue,
+    assertArgument
+} from "../utils/index.js";
+
+import { id } from "./id.js";
+
+import type { SignatureLike } from "../crypto/index.js";
+import type { BigNumberish, BytesLike } from "../utils/index.js";
+
+
+const padding = new Uint8Array(32);
+padding.fill(0);
+
+const BN__1 = BigInt(-1);
+const BN_0 = BigInt(0);
+const BN_1 = BigInt(1);
+const BN_MAX_UINT256 = BigInt("0xffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff");
+
+// @TODO: in v7, verifyingContract should be an AddressLike and use resolveAddress
+
+/**
+ *  The domain for an [[link-eip-712]] payload.
+ */
+export interface TypedDataDomain {
+    /**
+     *  The human-readable name of the signing domain.
+     */
+    name?: null | string;
+
+    /**
+     *  The major version of the signing domain.
+     */
+    version?: null | string;
+
+    /**
+     *  The chain ID of the signing domain.
+     */
+    chainId?: null | BigNumberish;
+
+    /**
+     *  The the address of the contract that will verify the signature.
+     */
+    verifyingContract?: null | string;
+
+    /**
+     *  A salt used for purposes decided by the specific domain.
+     */
+    salt?: null | BytesLike;
+};
+
+/**
+ *  A specific field of a structured [[link-eip-712]] type.
+ */
+export interface TypedDataField {
+    /**
+     *  The field name.
+     */
+    name: string;
+
+    /**
+     *  The type of the field.
+     */
+    type: string;
+};
+
+function hexPadRight(value: BytesLike): string {
+    const bytes = getBytes(value);
+    const padOffset = bytes.length % 32
+    if (padOffset) {
+        return concat([ bytes, padding.slice(padOffset) ]);
+    }
+    return hexlify(bytes);
+}
+
+const hexTrue = toBeHex(BN_1, 32);
+const hexFalse = toBeHex(BN_0, 32);
+
+const domainFieldTypes: Record<string, string> = {
+    name: "string",
+    version: "string",
+    chainId: "uint256",
+    verifyingContract: "address",
+    salt: "bytes32"
+};
+
+const domainFieldNames: Array<string> = [
+    "name", "version", "chainId", "verifyingContract", "salt"
+];
+
+function checkString(key: string): (value: any) => string {
+    return function (value: any){
+        assertArgument(typeof(value) === "string", `invalid domain value for ${ JSON.stringify(key) }`, `domain.${ key }`, value);
+        return value;
+    }
+}
+
+const domainChecks: Record<string, (value: any) => any> = {
+    name: checkString("name"),
+    version: checkString("version"),
+    chainId: function(_value: any) {
+        const value = getBigInt(_value, "domain.chainId");
+        assertArgument(value >= 0, "invalid chain ID", "domain.chainId", _value);
+        if (Number.isSafeInteger(value)) { return Number(value); }
+        return toQuantity(value);
+    },
+    verifyingContract: function(value: any) {
+        try {
+            return getAddress(value).toLowerCase();
+        } catch (error) { }
+        assertArgument(false, `invalid domain value "verifyingContract"`, "domain.verifyingContract", value);
+    },
+    salt: function(value: any) {
+        const bytes = getBytes(value, "domain.salt");
+        assertArgument(bytes.length === 32, `invalid domain value "salt"`, "domain.salt", value);
+        return hexlify(bytes);
+    }
+}
+
+function getBaseEncoder(type: string): null | ((value: any) => string) {
+    // intXX and uintXX
+    {
+        const match = type.match(/^(u?)int(\d+)$/);
+        if (match) {
+            const signed = (match[1] === "");
+
+            const width = parseInt(match[2]);
+            assertArgument(width % 8 === 0 && width !== 0 && width <= 256 && match[2] === String(width), "invalid numeric width", "type", type);
+
+            const boundsUpper = mask(BN_MAX_UINT256, signed ? (width - 1): width);
+            const boundsLower = signed ? ((boundsUpper + BN_1) * BN__1): BN_0;
+
+            return function(_value: BigNumberish) {
+                const value = getBigInt(_value, "value");
+
+                assertArgument(value >= boundsLower && value <= boundsUpper, `value out-of-bounds for ${ type }`, "value", value);
+
+                return toBeHex(signed ? toTwos(value, 256): value, 32);
+            };
+        }
+    }
+
+    // bytesXX
+    {
+        const match = type.match(/^bytes(\d+)$/);
+        if (match) {
+            const width = parseInt(match[1]);
+            assertArgument(width !== 0 && width <= 32 && match[1] === String(width), "invalid bytes width", "type", type);
+
+            return function(value: BytesLike) {
+                const bytes = getBytes(value);
+                assertArgument(bytes.length === width, `invalid length for ${ type }`, "value", value);
+                return hexPadRight(value);
+            };
+        }
+    }
+
+    switch (type) {
+        case "address": return function(value: string) {
+            return zeroPadValue(getAddress(value), 32);
+        };
+        case "bool": return function(value: boolean) {
+            return ((!value) ? hexFalse: hexTrue);
+        };
+        case "bytes": return function(value: BytesLike) {
+            return keccak256(value);
+        };
+        case "string": return function(value: string) {
+            return id(value);
+        };
+    }
+
+    return null;
+}
+
+function encodeType(name: string, fields: Array<TypedDataField>): string {
+    return `${ name }(${ fields.map(({ name, type }) => (type + " " + name)).join(",") })`;
+}
+
+type ArrayResult = {
+    base: string;         // The base type
+    index?: string;       // the full Index (if any)
+    array?: {             // The Array... (if index)
+        base: string;     // ...base type (same as above)
+        prefix: string;   // ...sans the final Index
+        count: number;    // ...the final Index (-1 for dynamic)
+    }
+};
+
+// foo[][3] => { base: "foo", index: "[][3]", array: {
+//     base: "foo", prefix: "foo[]", count: 3 } }
+function splitArray(type: string): ArrayResult {
+    const match = type.match(/^([^\x5b]*)((\x5b\d*\x5d)*)(\x5b(\d*)\x5d)$/);
+    if (match) {
+        return {
+            base: match[1],
+            index: (match[2] + match[4]),
+            array: {
+                base: match[1],
+                prefix: (match[1] + match[2]),
+                count: (match[5] ? parseInt(match[5]): -1),
+            }
+        };
+    }
+
+    return { base: type };
+}
+
+/**
+ *  A **TypedDataEncode** prepares and encodes [[link-eip-712]] payloads
+ *  for signed typed data.
+ *
+ *  This is useful for those that wish to compute various components of a
+ *  typed data hash, primary types, or sub-components, but generally the
+ *  higher level [[Signer-signTypedData]] is more useful.
+ */
+export class TypedDataEncoder {
+    /**
+     *  The primary type for the structured [[types]].
+     *
+     *  This is derived automatically from the [[types]], since no
+     *  recursion is possible, once the DAG for the types is consturcted
+     *  internally, the primary type must be the only remaining type with
+     *  no parent nodes.
+     */
+    readonly primaryType!: string;
+
+    readonly #types: string;
+
+    /**
+     *  The types.
+     */
+    get types(): Record<string, Array<TypedDataField>> {
+        return JSON.parse(this.#types);
+    }
+
+    readonly #fullTypes: Map<string, string>
+
+    readonly #encoderCache: Map<string, (value: any) => string>;
+
+    /**
+     *  Create a new **TypedDataEncoder** for %%types%%.
+     *
+     *  This performs all necessary checking that types are valid and
+     *  do not violate the [[link-eip-712]] structural constraints as
+     *  well as computes the [[primaryType]].
+     */
+    constructor(_types: Record<string, Array<TypedDataField>>) {
+        this.#fullTypes = new Map();
+        this.#encoderCache = new Map();
+
+        // Link struct types to their direct child structs
+        const links: Map<string, Set<string>> = new Map();
+
+        // Link structs to structs which contain them as a child
+        const parents: Map<string, Array<string>> = new Map();
+
+        // Link all subtypes within a given struct
+        const subtypes: Map<string, Set<string>> = new Map();
+
+        const types: Record<string, Array<TypedDataField>> = { };
+        Object.keys(_types).forEach((type) => {
+            types[type] = _types[type].map(({ name, type }) => {
+
+                // Normalize the base type (unless name conflict)
+                let { base, index } = splitArray(type);
+                if (base === "int" && !_types["int"]) { base = "int256"; }
+                if (base === "uint" && !_types["uint"]) { base = "uint256"; }
+
+                return { name, type: (base + (index || "")) };
+            });
+
+            links.set(type, new Set());
+            parents.set(type, [ ]);
+            subtypes.set(type, new Set());
+        });
+        this.#types = JSON.stringify(types);
+
+        for (const name in types) {
+            const uniqueNames: Set<string> = new Set();
+
+            for (const field of types[name]) {
+
+                // Check each field has a unique name
+                assertArgument(!uniqueNames.has(field.name), `duplicate variable name ${ JSON.stringify(field.name) } in ${ JSON.stringify(name) }`, "types", _types);
+                uniqueNames.add(field.name);
+
+                // Get the base type (drop any array specifiers)
+                const baseType = splitArray(field.type).base;
+                assertArgument(baseType !== name, `circular type reference to ${ JSON.stringify(baseType) }`, "types", _types);
+
+                // Is this a base encoding type?
+                const encoder = getBaseEncoder(baseType);
+                if (encoder) { continue; }
+
+                assertArgument(parents.has(baseType), `unknown type ${ JSON.stringify(baseType) }`, "types", _types);
+
+                // Add linkage
+                (parents.get(baseType) as Array<string>).push(name);
+                (links.get(name) as Set<string>).add(baseType);
+            }
+        }
+
+        // Deduce the primary type
+        const primaryTypes = Array.from(parents.keys()).filter((n) => ((parents.get(n) as Array<string>).length === 0));
+        assertArgument(primaryTypes.length !== 0, "missing primary type", "types", _types);
+        assertArgument(primaryTypes.length === 1, `ambiguous primary types or unused types: ${ primaryTypes.map((t) => (JSON.stringify(t))).join(", ") }`, "types", _types);
+
+        defineProperties<TypedDataEncoder>(this, { primaryType: primaryTypes[0] });
+
+        // Check for circular type references
+        function checkCircular(type: string, found: Set<string>) {
+            assertArgument(!found.has(type), `circular type reference to ${ JSON.stringify(type) }`, "types", _types);
+
+            found.add(type);
+
+            for (const child of (links.get(type) as Set<string>)) {
+                if (!parents.has(child)) { continue; }
+
+                // Recursively check children
+                checkCircular(child, found);
+
+                // Mark all ancestors as having this decendant
+                for (const subtype of found) {
+                    (subtypes.get(subtype) as Set<string>).add(child);
+                }
+            }
+
+            found.delete(type);
+        }
+        checkCircular(this.primaryType, new Set());
+
+        // Compute each fully describe type
+        for (const [ name, set ] of subtypes) {
+            const st = Array.from(set);
+            st.sort();
+            this.#fullTypes.set(name, encodeType(name, types[name]) + st.map((t) => encodeType(t, types[t])).join(""));
+        }
+    }
+
+    /**
+     *  Returnthe encoder for the specific %%type%%.
+     */
+    getEncoder(type: string): (value: any) => string {
+        let encoder = this.#encoderCache.get(type);
+        if (!encoder) {
+            encoder = this.#getEncoder(type);
+            this.#encoderCache.set(type, encoder);
+        }
+        return encoder;
+    }
+
+    #getEncoder(type: string): (value: any) => string {
+
+        // Basic encoder type (address, bool, uint256, etc)
+        {
+            const encoder = getBaseEncoder(type);
+            if (encoder) { return encoder; }
+        }
+
+        // Array
+        const array = splitArray(type).array;
+        if (array) {
+            const subtype = array.prefix;
+            const subEncoder = this.getEncoder(subtype);
+            return (value: Array<any>) => {
+                assertArgument(array.count === -1 || array.count === value.length, `array length mismatch; expected length ${ array.count }`, "value", value);
+
+                let result = value.map(subEncoder);
+                if (this.#fullTypes.has(subtype)) {
+                    result = result.map(keccak256);
+                }
+
+                return keccak256(concat(result));
+            };
+        }
+
+        // Struct
+        const fields = this.types[type];
+        if (fields) {
+            const encodedType = id(this.#fullTypes.get(type) as string);
+            return (value: Record<string, any>) => {
+                const values = fields.map(({ name, type }) => {
+                    const result = this.getEncoder(type)(value[name]);
+                    if (this.#fullTypes.has(type)) { return keccak256(result); }
+                    return result;
+                });
+                values.unshift(encodedType);
+                return concat(values);
+            }
+        }
+
+        assertArgument(false, `unknown type: ${ type }`, "type", type);
+    }
+
+    /**
+     *  Return the full type for %%name%%.
+     */
+    encodeType(name: string): string {
+        const result = this.#fullTypes.get(name);
+        assertArgument(result, `unknown type: ${ JSON.stringify(name) }`, "name", name);
+        return result;
+    }
+
+    /**
+     *  Return the encoded %%value%% for the %%type%%.
+     */
+    encodeData(type: string, value: any): string {
+        return this.getEncoder(type)(value);
+    }
+
+    /**
+     *  Returns the hash of %%value%% for the type of %%name%%.
+     */
+    hashStruct(name: string, value: Record<string, any>): string {
+        return keccak256(this.encodeData(name, value));
+    }
+
+    /**
+     *  Return the fulled encoded %%value%% for the [[types]].
+     */
+    encode(value: Record<string, any>): string {
+        return this.encodeData(this.primaryType, value);
+    }
+
+    /**
+     *  Return the hash of the fully encoded %%value%% for the [[types]].
+     */
+    hash(value: Record<string, any>): string {
+        return this.hashStruct(this.primaryType, value);
+    }
+
+    /**
+     *  @_ignore:
+     */
+    _visit(type: string, value: any, callback: (type: string, data: any) => any): any {
+        // Basic encoder type (address, bool, uint256, etc)
+        {
+            const encoder = getBaseEncoder(type);
+            if (encoder) { return callback(type, value); }
+        }
+
+        // Array
+        const array = splitArray(type).array;
+        if (array) {
+            assertArgument(array.count === -1 || array.count === value.length, `array length mismatch; expected length ${ array.count }`, "value", value);
+            return value.map((v: any) => this._visit(array.prefix, v, callback));
+        }
+
+        // Struct
+        const fields = this.types[type];
+        if (fields) {
+            return fields.reduce((accum, { name, type }) => {
+                accum[name] = this._visit(type, value[name], callback);
+                return accum;
+            }, <Record<string, any>>{});
+        }
+
+        assertArgument(false, `unknown type: ${ type }`, "type", type);
+    }
+
+    /**
+     *  Call %%calback%% for each value in %%value%%, passing the type and
+     *  component within %%value%%.
+     *
+     *  This is useful for replacing addresses or other transformation that
+     *  may be desired on each component, based on its type.
+     */
+    visit(value: Record<string, any>, callback: (type: string, data: any) => any): any {
+        return this._visit(this.primaryType, value, callback);
+    }
+
+    /**
+     *  Create a new **TypedDataEncoder** for %%types%%.
+     */
+    static from(types: Record<string, Array<TypedDataField>>): TypedDataEncoder {
+        return new TypedDataEncoder(types);
+    }
+
+    /**
+     *  Return the primary type for %%types%%.
+     */
+    static getPrimaryType(types: Record<string, Array<TypedDataField>>): string {
+        return TypedDataEncoder.from(types).primaryType;
+    }
+
+    /**
+     *  Return the hashed struct for %%value%% using %%types%% and %%name%%.
+     */
+    static hashStruct(name: string, types: Record<string, Array<TypedDataField>>, value: Record<string, any>): string {
+        return TypedDataEncoder.from(types).hashStruct(name, value);
+    }
+
+    /**
+     *  Return the domain hash for %%domain%%.
+     */
+    static hashDomain(domain: TypedDataDomain): string {
+        const domainFields: Array<TypedDataField> = [ ];
+        for (const name in domain) {
+            if ((<Record<string, any>>domain)[name] == null) { continue; }
+            const type = domainFieldTypes[name];
+            assertArgument(type, `invalid typed-data domain key: ${ JSON.stringify(name) }`, "domain", domain);
+            domainFields.push({ name, type });
+        }
+
+        domainFields.sort((a, b) => {
+            return domainFieldNames.indexOf(a.name) - domainFieldNames.indexOf(b.name);
+        });
+
+        return TypedDataEncoder.hashStruct("EIP712Domain", { EIP712Domain: domainFields }, domain);
+    }
+
+    /**
+     *  Return the fully encoded [[link-eip-712]] %%value%% for %%types%% with %%domain%%.
+     */
+    static encode(domain: TypedDataDomain, types: Record<string, Array<TypedDataField>>, value: Record<string, any>): string {
+        return concat([
+            "0x1901",
+            TypedDataEncoder.hashDomain(domain),
+            TypedDataEncoder.from(types).hash(value)
+        ]);
+    }
+
+    /**
+     *  Return the hash of the fully encoded [[link-eip-712]] %%value%% for %%types%% with %%domain%%.
+     */
+    static hash(domain: TypedDataDomain, types: Record<string, Array<TypedDataField>>, value: Record<string, any>): string {
+        return keccak256(TypedDataEncoder.encode(domain, types, value));
+    }
+
+    // Replaces all address types with ENS names with their looked up address
+    /**
+     * Resolves to the value from resolving all addresses in %%value%% for
+     * %%types%% and the %%domain%%.
+     */
+    static async resolveNames(domain: TypedDataDomain, types: Record<string, Array<TypedDataField>>, value: Record<string, any>, resolveName: (name: string) => Promise<string>): Promise<{ domain: TypedDataDomain, value: any }> {
+        // Make a copy to isolate it from the object passed in
+        domain = Object.assign({ }, domain);
+
+        // Allow passing null to ignore value
+        for (const key in domain) {
+            if ((<Record<string, any>>domain)[key] == null) {
+                delete (<Record<string, any>>domain)[key];
+            }
+        }
+
+        // Look up all ENS names
+        const ensCache: Record<string, string> = { };
+
+        // Do we need to look up the domain's verifyingContract?
+        if (domain.verifyingContract && !isHexString(domain.verifyingContract, 20)) {
+            ensCache[domain.verifyingContract] = "0x";
+        }
+
+        // We are going to use the encoder to visit all the base values
+        const encoder = TypedDataEncoder.from(types);
+
+        // Get a list of all the addresses
+        encoder.visit(value, (type: string, value: any) => {
+            if (type === "address" && !isHexString(value, 20)) {
+                ensCache[value] = "0x";
+            }
+            return value;
+        });
+
+        // Lookup each name
+        for (const name in ensCache) {
+            ensCache[name] = await resolveName(name);
+        }
+
+        // Replace the domain verifyingContract if needed
+        if (domain.verifyingContract && ensCache[domain.verifyingContract]) {
+            domain.verifyingContract = ensCache[domain.verifyingContract];
+        }
+
+        // Replace all ENS names with their address
+        value = encoder.visit(value, (type: string, value: any) => {
+            if (type === "address" && ensCache[value]) { return ensCache[value]; }
+            return value;
+        });
+
+        return { domain, value };
+    }
+
+    /**
+     *  Returns the JSON-encoded payload expected by nodes which implement
+     *  the JSON-RPC [[link-eip-712]] method.
+     */
+    static getPayload(domain: TypedDataDomain, types: Record<string, Array<TypedDataField>>, value: Record<string, any>): any {
+        // Validate the domain fields
+        TypedDataEncoder.hashDomain(domain);
+
+        // Derive the EIP712Domain Struct reference type
+        const domainValues: Record<string, any> = { };
+        const domainTypes: Array<{ name: string, type:string }> = [ ];
+
+        domainFieldNames.forEach((name) => {
+            const value = (<any>domain)[name];
+            if (value == null) { return; }
+            domainValues[name] = domainChecks[name](value);
+            domainTypes.push({ name, type: domainFieldTypes[name] });
+        });
+
+        const encoder = TypedDataEncoder.from(types);
+
+        // Get the normalized types
+        types = encoder.types;
+
+        const typesWithDomain = Object.assign({ }, types);
+        assertArgument(typesWithDomain.EIP712Domain == null, "types must not contain EIP712Domain type", "types.EIP712Domain", types);
+
+        typesWithDomain.EIP712Domain = domainTypes;
+
+        // Validate the data structures and types
+        encoder.encode(value);
+
+        return {
+            types: typesWithDomain,
+            domain: domainValues,
+            primaryType: encoder.primaryType,
+            message: encoder.visit(value, (type: string, value: any) => {
+
+                // bytes
+                if (type.match(/^bytes(\d*)/)) {
+                    return hexlify(getBytes(value));
+                }
+
+                // uint or int
+                if (type.match(/^u?int/)) {
+                    return getBigInt(value).toString();
+                }
+
+                switch (type) {
+                    case "address":
+                        return value.toLowerCase();
+                    case "bool":
+                        return !!value;
+                    case "string":
+                        assertArgument(typeof(value) === "string", "invalid string", "value", value);
+                        return value;
+                }
+
+                assertArgument(false, "unsupported type", "type", type);
+            })
+        };
+    }
+}
+
+/**
+ *  Compute the address used to sign the typed data for the %%signature%%.
+ */
+export function verifyTypedData(domain: TypedDataDomain, types: Record<string, Array<TypedDataField>>, value: Record<string, any>, signature: SignatureLike): string {
+    return recoverAddress(TypedDataEncoder.hash(domain, types, value), signature);
+}