diff --git a/barretenberg/ts/scripts/cjs_postprocess.sh b/barretenberg/ts/scripts/cjs_postprocess.sh
index ccfcfc2d8a2..8a805bcdd44 100755
--- a/barretenberg/ts/scripts/cjs_postprocess.sh
+++ b/barretenberg/ts/scripts/cjs_postprocess.sh
@@ -11,4 +11,6 @@ DIR="./dest/node-cjs"
 for FILE in $(find "$DIR" -name "*.js"); do
     # Use sed to replace 'import.meta.url' with '""'
     sed -i.bak 's/import\.meta\.url/""/g' "$FILE" && rm "$FILE.bak"
+    # Use sed to remove any lines postfixed // POSTPROCESS ESM ONLY
+    sed -i.bak '/\/\/ POSTPROCESS ESM ONLY$/d' "$FILE" && rm "$FILE.bak"
 done
\ No newline at end of file
diff --git a/barretenberg/ts/src/barretenberg/index.ts b/barretenberg/ts/src/barretenberg/index.ts
index 6019b24e88f..6b00a9b752a 100644
--- a/barretenberg/ts/src/barretenberg/index.ts
+++ b/barretenberg/ts/src/barretenberg/index.ts
@@ -65,7 +65,7 @@ export class BarretenbergSync extends BarretenbergApiSync {
 
   static getSingleton() {
     if (!barretenbergSyncSingleton) {
-      throw new Error('Initialise first via initSingleton().');
+      throw new Error('First call BarretenbergSync.initSingleton() on @aztec/bb.js module.');
     }
     return barretenbergSyncSingleton;
   }
@@ -75,10 +75,8 @@ export class BarretenbergSync extends BarretenbergApiSync {
   }
 }
 
-// If we're loading this module in a test environment, just init the singleton immediately for convienience.
-if (process.env.NODE_ENV === 'test') {
-  // Need to ignore for cjs build.
-  // eslint-disable-next-line @typescript-eslint/ban-ts-comment
-  // @ts-ignore
-  await BarretenbergSync.initSingleton();
-}
+// If we're in ESM environment, use top level await. CJS users need to call it manually.
+// Need to ignore for cjs build.
+// eslint-disable-next-line @typescript-eslint/ban-ts-comment
+// @ts-ignore
+await BarretenbergSync.initSingleton(); // POSTPROCESS ESM ONLY
diff --git a/yarn-project/aztec.js/src/api/init.ts b/yarn-project/aztec.js/src/api/init.ts
index 2b5203c9d0b..9654b9c8042 100644
--- a/yarn-project/aztec.js/src/api/init.ts
+++ b/yarn-project/aztec.js/src/api/init.ts
@@ -1 +1,10 @@
-export { init as initAztecJs } from '@aztec/foundation/crypto';
+import { init } from '@aztec/foundation/crypto';
+
+/**
+ * This should only be needed to be called in CJS environments that don't have top level await.
+ * Initializes any asynchronous subsystems required to use the library.
+ * At time of writing, this is just our foundation crypto lib.
+ */
+export async function initAztecJs() {
+  await init();
+}
diff --git a/yarn-project/aztec.js/src/index.ts b/yarn-project/aztec.js/src/index.ts
index 38f1bc8970f..353457cd6f5 100644
--- a/yarn-project/aztec.js/src/index.ts
+++ b/yarn-project/aztec.js/src/index.ts
@@ -16,6 +16,8 @@
  *   import { AztecAddress } from '@aztec/aztec.js/aztec_address';
  *   import { EthAddress } from '@aztec/aztec.js/eth_address';
  * ```
+ *
+ * TODO: Ultimately reimplement this mega exporter by mega exporting a granular api (then deprecate it).
  */
 export {
   WaitOpts,
@@ -118,7 +120,7 @@ export {
 // External devs will almost certainly have their own methods of doing these things.
 // If we want to use them in our own "aztec.js consuming code", import them from foundation as needed.
 export { ContractArtifact, FunctionArtifact, encodeArguments } from '@aztec/foundation/abi';
-export { sha256, init } from '@aztec/foundation/crypto';
+export { sha256 } from '@aztec/foundation/crypto';
 export { DebugLogger, createDebugLogger, onLog } from '@aztec/foundation/log';
 export { retry, retryUntil } from '@aztec/foundation/retry';
 export { sleep } from '@aztec/foundation/sleep';
@@ -127,6 +129,7 @@ export { fileURLToPath } from '@aztec/foundation/url';
 export { to2Fields, toBigInt } from '@aztec/foundation/serialize';
 export { toBigIntBE } from '@aztec/foundation/bigint-buffer';
 export { makeFetch } from '@aztec/foundation/json-rpc/client';
+export { FieldsOf } from '@aztec/foundation/types';
 
 export {
   DeployL1Contracts,
@@ -135,4 +138,7 @@ export {
   deployL1Contracts,
 } from '@aztec/ethereum';
 
-export { FieldsOf } from '@aztec/foundation/types';
+// Start of section that exports public api via granular api.
+// Here you *can* do `export *` as the granular api defacto exports things explicitly.
+// This entire index file will be deprecated at some point after we're satisfied.
+export * from './api/init.js';
diff --git a/yarn-project/circuits.js/src/barretenberg/crypto/aes128/index.test.ts b/yarn-project/circuits.js/src/barretenberg/crypto/aes128/index.test.ts
index df34d06d305..9b8afc328e2 100644
--- a/yarn-project/circuits.js/src/barretenberg/crypto/aes128/index.test.ts
+++ b/yarn-project/circuits.js/src/barretenberg/crypto/aes128/index.test.ts
@@ -1,5 +1,3 @@
-import { init } from '@aztec/foundation/crypto';
-
 import { createCipheriv, createDecipheriv, randomBytes } from 'crypto';
 
 import { Aes128 } from './index.js';
@@ -7,8 +5,7 @@ import { Aes128 } from './index.js';
 describe('aes128', () => {
   let aes128!: Aes128;
 
-  beforeAll(async () => {
-    await init();
+  beforeAll(() => {
     aes128 = new Aes128();
   });
 
diff --git a/yarn-project/circuits.js/src/barretenberg/crypto/grumpkin/index.test.ts b/yarn-project/circuits.js/src/barretenberg/crypto/grumpkin/index.test.ts
index 671c019291b..154ab39075f 100644
--- a/yarn-project/circuits.js/src/barretenberg/crypto/grumpkin/index.test.ts
+++ b/yarn-project/circuits.js/src/barretenberg/crypto/grumpkin/index.test.ts
@@ -1,4 +1,3 @@
-import { init } from '@aztec/foundation/crypto';
 import { createDebugLogger } from '@aztec/foundation/log';
 
 import { GrumpkinScalar, Point } from '../../../index.js';
@@ -9,8 +8,7 @@ const debug = createDebugLogger('bb:grumpkin_test');
 describe('grumpkin', () => {
   let grumpkin!: Grumpkin;
 
-  beforeAll(async () => {
-    await init();
+  beforeAll(() => {
     grumpkin = new Grumpkin();
   });
 
diff --git a/yarn-project/cli/src/cmds/add_note.ts b/yarn-project/cli/src/cmds/add_note.ts
index 64340034370..33ad5a52f80 100644
--- a/yarn-project/cli/src/cmds/add_note.ts
+++ b/yarn-project/cli/src/cmds/add_note.ts
@@ -3,7 +3,7 @@ import { DebugLogger } from '@aztec/foundation/log';
 import { ExtendedNote, Note, TxHash } from '@aztec/types';
 
 import { createCompatibleClient } from '../client.js';
-import { parseFields } from '../utils.js';
+import { parseFields } from '../parse_args.js';
 
 /**
  *
diff --git a/yarn-project/cli/src/index.ts b/yarn-project/cli/src/index.ts
index 27a7275880f..08fd0c44b5e 100644
--- a/yarn-project/cli/src/index.ts
+++ b/yarn-project/cli/src/index.ts
@@ -1,4 +1,3 @@
-import { initAztecJs } from '@aztec/aztec.js/init';
 import { DebugLogger, LogFn } from '@aztec/foundation/log';
 import { fileURLToPath } from '@aztec/foundation/url';
 import { addNoirCompilerCommanderActions } from '@aztec/noir-compiler/cli';
@@ -22,7 +21,7 @@ import {
   parsePublicKey,
   parseSaltFromHexString,
   parseTxHash,
-} from './utils.js';
+} from './parse_args.js';
 
 /**
  * If we can successfully resolve 'host.docker.internal', then we are running in a container, and we should treat
@@ -63,8 +62,6 @@ export function getProgram(log: LogFn, debugLogger: DebugLogger): Command {
       .argParser(parsePrivateKey)
       .makeOptionMandatory(mandatory);
 
-  program.hook('preAction', initAztecJs);
-
   program
     .command('deploy-l1-contracts')
     .description('Deploys all necessary Ethereum contracts for Aztec.')
diff --git a/yarn-project/cli/src/parse_args.ts b/yarn-project/cli/src/parse_args.ts
new file mode 100644
index 00000000000..e2641005cd2
--- /dev/null
+++ b/yarn-project/cli/src/parse_args.ts
@@ -0,0 +1,248 @@
+import { FunctionSelector } from '@aztec/aztec.js/abi';
+import { AztecAddress } from '@aztec/aztec.js/aztec_address';
+import { EthAddress } from '@aztec/aztec.js/eth_address';
+import { Fr, GrumpkinScalar, Point } from '@aztec/aztec.js/fields';
+import { LogId } from '@aztec/aztec.js/log_id';
+import { TxHash } from '@aztec/aztec.js/tx_hash';
+
+import { InvalidArgumentError } from 'commander';
+
+/**
+ * Removes the leading 0x from a hex string. If no leading 0x is found the string is returned unchanged.
+ * @param hex - A hex string
+ * @returns A new string with leading 0x removed
+ */
+const stripLeadingHex = (hex: string) => {
+  if (hex.length > 2 && hex.startsWith('0x')) {
+    return hex.substring(2);
+  }
+  return hex;
+};
+
+/**
+ * Parses a hex encoded string to an Fr integer to be used as salt
+ * @param str - Hex encoded string
+ * @returns A integer to be used as salt
+ */
+export function parseSaltFromHexString(str: string): Fr {
+  const hex = stripLeadingHex(str);
+
+  // ensure it's a hex string
+  if (!hex.match(/^[0-9a-f]+$/i)) {
+    throw new InvalidArgumentError('Invalid hex string');
+  }
+
+  // pad it so that we may read it as a buffer.
+  // Buffer needs _exactly_ two hex characters per byte
+  const padded = hex.length % 2 === 1 ? '0' + hex : hex;
+
+  // finally, turn it into an integer
+  return Fr.fromBuffer(Buffer.from(padded, 'hex'));
+}
+
+/**
+ * Parses an AztecAddress from a string.
+ * @param address - A serialized Aztec address
+ * @returns An Aztec address
+ * @throws InvalidArgumentError if the input string is not valid.
+ */
+export function parseAztecAddress(address: string): AztecAddress {
+  try {
+    return AztecAddress.fromString(address);
+  } catch {
+    throw new InvalidArgumentError(`Invalid address: ${address}`);
+  }
+}
+
+/**
+ * Parses an Ethereum address from a string.
+ * @param address - A serialized Ethereum address
+ * @returns An Ethereum address
+ * @throws InvalidArgumentError if the input string is not valid.
+ */
+export function parseEthereumAddress(address: string): EthAddress {
+  try {
+    return EthAddress.fromString(address);
+  } catch {
+    throw new InvalidArgumentError(`Invalid address: ${address}`);
+  }
+}
+
+/**
+ * Parses an AztecAddress from a string.
+ * @param address - A serialized Aztec address
+ * @returns An Aztec address
+ * @throws InvalidArgumentError if the input string is not valid.
+ */
+export function parseOptionalAztecAddress(address: string): AztecAddress | undefined {
+  if (!address) {
+    return undefined;
+  }
+  return parseAztecAddress(address);
+}
+
+/**
+ * Parses an optional log ID string into a LogId object.
+ *
+ * @param logId - The log ID string to parse.
+ * @returns The parsed LogId object, or undefined if the log ID is missing or empty.
+ */
+export function parseOptionalLogId(logId: string): LogId | undefined {
+  if (!logId) {
+    return undefined;
+  }
+  return LogId.fromString(logId);
+}
+
+/**
+ * Parses a selector from a string.
+ * @param selector - A serialized selector.
+ * @returns A selector.
+ * @throws InvalidArgumentError if the input string is not valid.
+ */
+export function parseOptionalSelector(selector: string): FunctionSelector | undefined {
+  if (!selector) {
+    return undefined;
+  }
+  try {
+    return FunctionSelector.fromString(selector);
+  } catch {
+    throw new InvalidArgumentError(`Invalid selector: ${selector}`);
+  }
+}
+
+/**
+ * Parses a string into an integer or returns undefined if the input is falsy.
+ *
+ * @param value - The string to parse into an integer.
+ * @returns The parsed integer, or undefined if the input string is falsy.
+ * @throws If the input is not a valid integer.
+ */
+export function parseOptionalInteger(value: string): number | undefined {
+  if (!value) {
+    return undefined;
+  }
+  const parsed = Number(value);
+  if (!Number.isInteger(parsed)) {
+    throw new InvalidArgumentError('Invalid integer.');
+  }
+  return parsed;
+}
+
+/**
+ * Parses a TxHash from a string.
+ * @param txHash - A transaction hash
+ * @returns A TxHash instance
+ * @throws InvalidArgumentError if the input string is not valid.
+ */
+export function parseTxHash(txHash: string): TxHash {
+  try {
+    return TxHash.fromString(txHash);
+  } catch {
+    throw new InvalidArgumentError(`Invalid transaction hash: ${txHash}`);
+  }
+}
+
+/**
+ * Parses an optional TxHash from a string.
+ * Calls parseTxHash internally.
+ * @param txHash - A transaction hash
+ * @returns A TxHash instance, or undefined if the input string is falsy.
+ * @throws InvalidArgumentError if the input string is not valid.
+ */
+export function parseOptionalTxHash(txHash: string): TxHash | undefined {
+  if (!txHash) {
+    return undefined;
+  }
+  return parseTxHash(txHash);
+}
+
+/**
+ * Parses a public key from a string.
+ * @param publicKey - A public key
+ * @returns A Point instance
+ * @throws InvalidArgumentError if the input string is not valid.
+ */
+export function parsePublicKey(publicKey: string): Point {
+  try {
+    return Point.fromString(publicKey);
+  } catch (err) {
+    throw new InvalidArgumentError(`Invalid public key: ${publicKey}`);
+  }
+}
+
+/**
+ * Parses a partial address from a string.
+ * @param address - A partial address
+ * @returns A Fr instance
+ * @throws InvalidArgumentError if the input string is not valid.
+ */
+export function parsePartialAddress(address: string): Fr {
+  try {
+    return Fr.fromString(address);
+  } catch (err) {
+    throw new InvalidArgumentError(`Invalid partial address: ${address}`);
+  }
+}
+
+/**
+ * Parses a private key from a string.
+ * @param privateKey - A string
+ * @returns A private key
+ * @throws InvalidArgumentError if the input string is not valid.
+ */
+export function parsePrivateKey(privateKey: string): GrumpkinScalar {
+  try {
+    const value = GrumpkinScalar.fromString(privateKey);
+    // most likely a badly formatted key was passed
+    if (value.isZero()) {
+      throw new Error('Private key must not be zero');
+    }
+
+    return value;
+  } catch (err) {
+    throw new InvalidArgumentError(`Invalid private key: ${privateKey}`);
+  }
+}
+
+/**
+ * Parses a field from a string.
+ * @param field - A string representing the field.
+ * @returns A field.
+ * @throws InvalidArgumentError if the input string is not valid.
+ */
+export function parseField(field: string): Fr {
+  try {
+    const isHex = field.startsWith('0x') || field.match(new RegExp(`^[0-9a-f]{${Fr.SIZE_IN_BYTES * 2}}$`, 'i'));
+    if (isHex) {
+      return Fr.fromString(field);
+    }
+
+    if (['true', 'false'].includes(field)) {
+      return new Fr(field === 'true');
+    }
+
+    const isNumber = +field || field === '0';
+    if (isNumber) {
+      return new Fr(BigInt(field));
+    }
+
+    const isBigInt = field.endsWith('n');
+    if (isBigInt) {
+      return new Fr(BigInt(field.replace(/n$/, '')));
+    }
+
+    return new Fr(BigInt(field));
+  } catch (err) {
+    throw new InvalidArgumentError(`Invalid field: ${field}`);
+  }
+}
+
+/**
+ * Parses an array of strings to Frs.
+ * @param fields - An array of strings representing the fields.
+ * @returns An array of Frs.
+ */
+export function parseFields(fields: string[]): Fr[] {
+  return fields.map(parseField);
+}
diff --git a/yarn-project/cli/src/test/utils.test.ts b/yarn-project/cli/src/test/utils.test.ts
index e465138083b..d0c9ff1b7ef 100644
--- a/yarn-project/cli/src/test/utils.test.ts
+++ b/yarn-project/cli/src/test/utils.test.ts
@@ -5,7 +5,8 @@ import { InvalidArgumentError } from 'commander';
 import { MockProxy, mock } from 'jest-mock-extended';
 
 import { encodeArgs } from '../encoding.js';
-import { getTxSender, parseSaltFromHexString, stripLeadingHex } from '../utils.js';
+import { parseSaltFromHexString } from '../parse_args.js';
+import { getTxSender, stripLeadingHex } from '../utils.js';
 import { mockContractArtifact } from './mocks.js';
 
 describe('CLI Utils', () => {
diff --git a/yarn-project/cli/src/utils.ts b/yarn-project/cli/src/utils.ts
index ed8dd3cc017..40867e8fbb0 100644
--- a/yarn-project/cli/src/utils.ts
+++ b/yarn-project/cli/src/utils.ts
@@ -1,11 +1,7 @@
-import { type ContractArtifact, type FunctionArtifact, FunctionSelector } from '@aztec/aztec.js/abi';
+import { type ContractArtifact, type FunctionArtifact } from '@aztec/aztec.js/abi';
 import { AztecAddress } from '@aztec/aztec.js/aztec_address';
-import { EthAddress } from '@aztec/aztec.js/eth_address';
 import { type L1ContractArtifactsForDeployment } from '@aztec/aztec.js/ethereum';
-import { Fr, GrumpkinScalar, Point } from '@aztec/aztec.js/fields';
 import { type PXE } from '@aztec/aztec.js/interfaces/pxe';
-import { LogId } from '@aztec/aztec.js/log_id';
-import { TxHash } from '@aztec/aztec.js/tx_hash';
 import { DebugLogger, LogFn } from '@aztec/foundation/log';
 
 import { CommanderError, InvalidArgumentError } from 'commander';
@@ -182,234 +178,6 @@ export const stripLeadingHex = (hex: string) => {
   return hex;
 };
 
-/**
- * Parses a hex encoded string to an Fr integer to be used as salt
- * @param str - Hex encoded string
- * @returns A integer to be used as salt
- */
-export function parseSaltFromHexString(str: string): Fr {
-  const hex = stripLeadingHex(str);
-
-  // ensure it's a hex string
-  if (!hex.match(/^[0-9a-f]+$/i)) {
-    throw new InvalidArgumentError('Invalid hex string');
-  }
-
-  // pad it so that we may read it as a buffer.
-  // Buffer needs _exactly_ two hex characters per byte
-  const padded = hex.length % 2 === 1 ? '0' + hex : hex;
-
-  // finally, turn it into an integer
-  return Fr.fromBuffer(Buffer.from(padded, 'hex'));
-}
-
-/**
- * Parses an AztecAddress from a string.
- * @param address - A serialized Aztec address
- * @returns An Aztec address
- * @throws InvalidArgumentError if the input string is not valid.
- */
-export function parseAztecAddress(address: string): AztecAddress {
-  try {
-    return AztecAddress.fromString(address);
-  } catch {
-    throw new InvalidArgumentError(`Invalid address: ${address}`);
-  }
-}
-
-/**
- * Parses an Ethereum address from a string.
- * @param address - A serialized Ethereum address
- * @returns An Ethereum address
- * @throws InvalidArgumentError if the input string is not valid.
- */
-export function parseEthereumAddress(address: string): EthAddress {
-  try {
-    return EthAddress.fromString(address);
-  } catch {
-    throw new InvalidArgumentError(`Invalid address: ${address}`);
-  }
-}
-
-/**
- * Parses an AztecAddress from a string.
- * @param address - A serialized Aztec address
- * @returns An Aztec address
- * @throws InvalidArgumentError if the input string is not valid.
- */
-export function parseOptionalAztecAddress(address: string): AztecAddress | undefined {
-  if (!address) {
-    return undefined;
-  }
-  return parseAztecAddress(address);
-}
-
-/**
- * Parses an optional log ID string into a LogId object.
- *
- * @param logId - The log ID string to parse.
- * @returns The parsed LogId object, or undefined if the log ID is missing or empty.
- */
-export function parseOptionalLogId(logId: string): LogId | undefined {
-  if (!logId) {
-    return undefined;
-  }
-  return LogId.fromString(logId);
-}
-
-/**
- * Parses a selector from a string.
- * @param selector - A serialized selector.
- * @returns A selector.
- * @throws InvalidArgumentError if the input string is not valid.
- */
-export function parseOptionalSelector(selector: string): FunctionSelector | undefined {
-  if (!selector) {
-    return undefined;
-  }
-  try {
-    return FunctionSelector.fromString(selector);
-  } catch {
-    throw new InvalidArgumentError(`Invalid selector: ${selector}`);
-  }
-}
-
-/**
- * Parses a string into an integer or returns undefined if the input is falsy.
- *
- * @param value - The string to parse into an integer.
- * @returns The parsed integer, or undefined if the input string is falsy.
- * @throws If the input is not a valid integer.
- */
-export function parseOptionalInteger(value: string): number | undefined {
-  if (!value) {
-    return undefined;
-  }
-  const parsed = Number(value);
-  if (!Number.isInteger(parsed)) {
-    throw new InvalidArgumentError('Invalid integer.');
-  }
-  return parsed;
-}
-
-/**
- * Parses a TxHash from a string.
- * @param txHash - A transaction hash
- * @returns A TxHash instance
- * @throws InvalidArgumentError if the input string is not valid.
- */
-export function parseTxHash(txHash: string): TxHash {
-  try {
-    return TxHash.fromString(txHash);
-  } catch {
-    throw new InvalidArgumentError(`Invalid transaction hash: ${txHash}`);
-  }
-}
-
-/**
- * Parses an optional TxHash from a string.
- * Calls parseTxHash internally.
- * @param txHash - A transaction hash
- * @returns A TxHash instance, or undefined if the input string is falsy.
- * @throws InvalidArgumentError if the input string is not valid.
- */
-export function parseOptionalTxHash(txHash: string): TxHash | undefined {
-  if (!txHash) {
-    return undefined;
-  }
-  return parseTxHash(txHash);
-}
-
-/**
- * Parses a public key from a string.
- * @param publicKey - A public key
- * @returns A Point instance
- * @throws InvalidArgumentError if the input string is not valid.
- */
-export function parsePublicKey(publicKey: string): Point {
-  try {
-    return Point.fromString(publicKey);
-  } catch (err) {
-    throw new InvalidArgumentError(`Invalid public key: ${publicKey}`);
-  }
-}
-
-/**
- * Parses a partial address from a string.
- * @param address - A partial address
- * @returns A Fr instance
- * @throws InvalidArgumentError if the input string is not valid.
- */
-export function parsePartialAddress(address: string): Fr {
-  try {
-    return Fr.fromString(address);
-  } catch (err) {
-    throw new InvalidArgumentError(`Invalid partial address: ${address}`);
-  }
-}
-
-/**
- * Parses a private key from a string.
- * @param privateKey - A string
- * @returns A private key
- * @throws InvalidArgumentError if the input string is not valid.
- */
-export function parsePrivateKey(privateKey: string): GrumpkinScalar {
-  try {
-    const value = GrumpkinScalar.fromString(privateKey);
-    // most likely a badly formatted key was passed
-    if (value.isZero()) {
-      throw new Error('Private key must not be zero');
-    }
-
-    return value;
-  } catch (err) {
-    throw new InvalidArgumentError(`Invalid private key: ${privateKey}`);
-  }
-}
-
-/**
- * Parses a field from a string.
- * @param field - A string representing the field.
- * @returns A field.
- * @throws InvalidArgumentError if the input string is not valid.
- */
-export function parseField(field: string): Fr {
-  try {
-    const isHex = field.startsWith('0x') || field.match(new RegExp(`^[0-9a-f]{${Fr.SIZE_IN_BYTES * 2}}$`, 'i'));
-    if (isHex) {
-      return Fr.fromString(field);
-    }
-
-    if (['true', 'false'].includes(field)) {
-      return new Fr(field === 'true');
-    }
-
-    const isNumber = +field || field === '0';
-    if (isNumber) {
-      return new Fr(BigInt(field));
-    }
-
-    const isBigInt = field.endsWith('n');
-    if (isBigInt) {
-      return new Fr(BigInt(field.replace(/n$/, '')));
-    }
-
-    return new Fr(BigInt(field));
-  } catch (err) {
-    throw new InvalidArgumentError(`Invalid field: ${field}`);
-  }
-}
-
-/**
- * Parses an array of strings to Frs.
- * @param fields - An array of strings representing the fields.
- * @returns An array of Frs.
- */
-export function parseFields(fields: string[]): Fr[] {
-  return fields.map(parseField);
-}
-
 /**
  * Updates a file in place atomically.
  * @param filePath - Path to file
diff --git a/yarn-project/end-to-end/src/shared/browser.ts b/yarn-project/end-to-end/src/shared/browser.ts
index 9c7cfdfc154..72b064bc903 100644
--- a/yarn-project/end-to-end/src/shared/browser.ts
+++ b/yarn-project/end-to-end/src/shared/browser.ts
@@ -84,9 +84,8 @@ export const browserTestSuite = (setup: () => Server, pageLogger: AztecJs.DebugL
     });
 
     it('Loads Aztec.js in the browser', async () => {
-      const generatePublicKeyExists = await page.evaluate(async () => {
-        const { generatePublicKey, init } = window.AztecJs;
-        await init();
+      const generatePublicKeyExists = await page.evaluate(() => {
+        const { generatePublicKey } = window.AztecJs;
         return typeof generatePublicKey === 'function';
       });
       expect(generatePublicKeyExists).toBe(true);
diff --git a/yarn-project/foundation/src/abi/abi_coder.ts b/yarn-project/foundation/src/abi/abi_coder.ts
index 6971b423757..a702e65153a 100644
--- a/yarn-project/foundation/src/abi/abi_coder.ts
+++ b/yarn-project/foundation/src/abi/abi_coder.ts
@@ -1,4 +1,4 @@
-import { ABIType } from '@aztec/foundation/abi';
+import { type ABIType } from './abi.js';
 
 /**
  * Get the size of an ABI type in field elements.
diff --git a/yarn-project/foundation/src/abi/decoder.ts b/yarn-project/foundation/src/abi/decoder.ts
index 9ea69388f76..cd37ba361e5 100644
--- a/yarn-project/foundation/src/abi/decoder.ts
+++ b/yarn-project/foundation/src/abi/decoder.ts
@@ -1,5 +1,5 @@
-import { ABIParameter, ABIType, ABIVariable, FunctionArtifact } from '@aztec/foundation/abi';
-import { Fr } from '@aztec/foundation/fields';
+import { Fr } from '../fields/index.js';
+import { ABIParameter, type ABIType, ABIVariable, FunctionArtifact } from './abi.js';
 
 /**
  * The type of our decoded ABI.
diff --git a/yarn-project/foundation/src/abi/encoder.ts b/yarn-project/foundation/src/abi/encoder.ts
index 2e4b1844060..a4db8e24230 100644
--- a/yarn-project/foundation/src/abi/encoder.ts
+++ b/yarn-project/foundation/src/abi/encoder.ts
@@ -1,6 +1,6 @@
-import { ABIType, FunctionAbi, isAddressStruct } from '@aztec/foundation/abi';
-
 import { Fr } from '../fields/index.js';
+import { ABIType, FunctionAbi } from './abi.js';
+import { isAddressStruct } from './utils.js';
 
 /**
  * Encodes arguments for a function call.
diff --git a/yarn-project/foundation/src/abi/function_selector.ts b/yarn-project/foundation/src/abi/function_selector.ts
index df53ef9a1fb..de0b879cf6b 100644
--- a/yarn-project/foundation/src/abi/function_selector.ts
+++ b/yarn-project/foundation/src/abi/function_selector.ts
@@ -1,9 +1,11 @@
-import { ABIParameter, decodeFunctionSignature } from '@aztec/foundation/abi';
 import { toBigIntBE, toBufferBE } from '@aztec/foundation/bigint-buffer';
-import { keccak } from '@aztec/foundation/crypto';
-import { Fr } from '@aztec/foundation/fields';
 import { BufferReader } from '@aztec/foundation/serialize';
 
+import { keccak } from '../crypto/keccak/index.js';
+import { Fr } from '../fields/index.js';
+import { ABIParameter } from './abi.js';
+import { decodeFunctionSignature } from './decoder.js';
+
 /**
  * A function selector is the first 4 bytes of the hash of a function signature.
  */
diff --git a/yarn-project/foundation/src/abi/utils.ts b/yarn-project/foundation/src/abi/utils.ts
index b2ee62d2dd5..d7d15a4d94a 100644
--- a/yarn-project/foundation/src/abi/utils.ts
+++ b/yarn-project/foundation/src/abi/utils.ts
@@ -1,4 +1,4 @@
-import { ABIType } from './abi.js';
+import { type ABIType } from './abi.js';
 
 /**
  * Returns whether the ABI type is an Aztec or Ethereum Address defined in Aztec.nr.
diff --git a/yarn-project/foundation/src/eth-address/index.ts b/yarn-project/foundation/src/eth-address/index.ts
index 2571f09790c..76587ecab26 100644
--- a/yarn-project/foundation/src/eth-address/index.ts
+++ b/yarn-project/foundation/src/eth-address/index.ts
@@ -1,4 +1,5 @@
-import { keccak256String, randomBytes } from '../crypto/index.js';
+import { keccak256String } from '../crypto/keccak/index.js';
+import { randomBytes } from '../crypto/random/index.js';
 import { Fr } from '../fields/index.js';
 import { BufferReader } from '../serialize/index.js';
 
diff --git a/yarn-project/foundation/src/fields/fields.ts b/yarn-project/foundation/src/fields/fields.ts
index 591b57f6892..90600643cfe 100644
--- a/yarn-project/foundation/src/fields/fields.ts
+++ b/yarn-project/foundation/src/fields/fields.ts
@@ -1,5 +1,5 @@
 import { toBigIntBE, toBufferBE } from '../bigint-buffer/index.js';
-import { randomBytes } from '../crypto/index.js';
+import { randomBytes } from '../crypto/random/index.js';
 import { BufferReader } from '../serialize/buffer_reader.js';
 
 const ZERO_BUFFER = Buffer.alloc(32);
diff --git a/yarn-project/types/src/tx/tx_hash.ts b/yarn-project/types/src/tx/tx_hash.ts
index 138aa6dbe0f..00003456ee3 100644
--- a/yarn-project/types/src/tx/tx_hash.ts
+++ b/yarn-project/types/src/tx/tx_hash.ts
@@ -1,4 +1,3 @@
-import { assertMemberLength } from '@aztec/circuits.js';
 import { deserializeBigInt, serializeBigInt } from '@aztec/foundation/serialize';
 
 /**
@@ -21,7 +20,9 @@ export class TxHash {
      */
     public buffer: Buffer,
   ) {
-    assertMemberLength(this, 'buffer', TxHash.SIZE);
+    if (buffer.length !== TxHash.SIZE) {
+      throw new Error(`Expected buffer to have length ${TxHash.SIZE} but was ${buffer.length}`);
+    }
   }
 
   /**