diff --git a/libs/credentials/src/index.test.ts b/libs/credentials/src/index.test.ts
index 41b670f2..eef550f8 100644
--- a/libs/credentials/src/index.test.ts
+++ b/libs/credentials/src/index.test.ts
@@ -1,6 +1,7 @@
 import { BigNumber } from "ethers"
 import blockchainBalance from "./validators/blockchainBalance"
 import blockchainTransactions from "./validators/blockchainTransactions"
+import githubPersonalStars from "./validators/githubPersonalStars"
 import addProvider from "./addProvider"
 import addProviders from "./addProviders"
 import addValidator from "./addValidator"
@@ -13,6 +14,8 @@ import {
     validateCredentials,
     validateManyCredentials
 } from "./validateCredentials"
+import { testUtils } from "."
+import { evaluate, tokenize } from "./evaluateExpression"
 
 describe("Credentials library", () => {
     describe("# addProvider", () => {
@@ -81,8 +84,9 @@ describe("Credentials library", () => {
             getTransactionCount: jest.fn()
         }
         it("Should return true if an account has a balance greater than or equal to 10", async () => {
-            jsonRpcProviderMocked.getBalance.mockReturnValue(BigNumber.from(12))
-            jsonRpcProviderMocked.getTransactionCount.mockReturnValue(12)
+            jsonRpcProviderMocked.getBalance.mockReturnValue(
+                BigNumber.from("12000000000000000000")
+            )
 
             const result = await validateCredentials(
                 {
@@ -101,7 +105,9 @@ describe("Credentials library", () => {
             expect(result).toBeTruthy()
         })
         it("Should return true if an account has a balance greater than or equal to 10 and greater than or equal to 10 transactions", async () => {
-            jsonRpcProviderMocked.getBalance.mockReturnValue(BigNumber.from(12))
+            jsonRpcProviderMocked.getBalance.mockReturnValue(
+                BigNumber.from("12000000000000000000")
+            )
             jsonRpcProviderMocked.getTransactionCount.mockReturnValue(12)
 
             const credentials = [
@@ -140,5 +146,139 @@ describe("Credentials library", () => {
 
             expect(result).toBeTruthy()
         })
+        it("Should validate many credentials with parentheses in the expression", async () => {
+            // This will meet the criteria
+            jsonRpcProviderMocked.getBalance.mockReturnValue(
+                BigNumber.from("12000000000000000000")
+            )
+            // This will not meet the criteria
+            jsonRpcProviderMocked.getTransactionCount.mockReturnValue(8)
+            // This will meet the criteria
+            testUtils.mockAPIOnce(
+                Array.from(Array(20).keys()).map(() => ({
+                    stargazers_count: 10
+                }))
+            )
+
+            const credentials = [
+                {
+                    id: blockchainBalance.id,
+                    criteria: {
+                        minBalance: "10",
+                        network: "sepolia"
+                    }
+                },
+                {
+                    id: blockchainTransactions.id,
+                    criteria: {
+                        minTransactions: 10,
+                        network: "sepolia"
+                    }
+                },
+                {
+                    id: githubPersonalStars.id,
+                    criteria: {
+                        minStars: 100
+                    }
+                }
+            ]
+
+            const contexts = [
+                {
+                    address: "0x",
+                    jsonRpcProvider: jsonRpcProviderMocked
+                },
+                {
+                    address: "0x",
+                    jsonRpcProvider: jsonRpcProviderMocked
+                },
+                {
+                    profile: {},
+                    accessTokens: { github: "token" }
+                }
+            ]
+            const expression = ["", "and", "(", "", "or", "", ")"]
+            const result = await validateManyCredentials(
+                credentials,
+                contexts,
+                expression
+            )
+
+            expect(result).toBeTruthy()
+        })
+    })
+    describe("# evaluateExpression", () => {
+        describe("# tokenize", () => {
+            it("Should sucessfully tokenize a logical expression", () => {
+                const expression = "true and false or ( true and true )"
+
+                const tokens = tokenize(expression)
+
+                const result = [
+                    "true",
+                    "and",
+                    "false",
+                    "or",
+                    "(",
+                    "true",
+                    "and",
+                    "true",
+                    ")"
+                ]
+
+                expect(tokens).toStrictEqual(result)
+            })
+        })
+        describe("# evaluate", () => {
+            it("Should sucessfully evaluate a logical expression with the and operator", () => {
+                const expression = ["true", "and", "false"]
+                const result = evaluate(expression)
+                expect(result).toBeFalsy()
+            })
+            it("Should sucessfully evaluate a logical expression with the or operator", () => {
+                const expression = ["true", "or", "false"]
+                const result = evaluate(expression)
+                expect(result).toBeTruthy()
+            })
+            it("Should sucessfully evaluate a logical expression with the not operator", () => {
+                const expression = ["not", "false"]
+                const result = evaluate(expression)
+                expect(result).toBeTruthy()
+            })
+            it("Should sucessfully evaluate a logical expression with the xor operator", () => {
+                const expression = ["false", "xor", "true"]
+                const result = evaluate(expression)
+                expect(result).toBeTruthy()
+            })
+            it("Should sucessfully evaluate a logical expression with the and or not and xor operators", () => {
+                const expression = [
+                    "true",
+                    "and",
+                    "false",
+                    "or",
+                    "not",
+                    "false",
+                    "xor",
+                    "true"
+                ]
+                const result = evaluate(expression)
+                expect(result).toBeFalsy()
+            })
+            it("Should sucessfully evaluate a logical expression with parentheses", () => {
+                const expression = [
+                    "true",
+                    "and",
+                    "false",
+                    "or",
+                    "(",
+                    "true",
+                    "and",
+                    "true",
+                    ")"
+                ]
+                const result = evaluate(expression)
+                expect(result).toBeTruthy()
+            })
+        })
     })
 })