diff --git a/interfaces/index.ts b/interfaces/index.ts
index 5eaaa18..77e3ee8 100644
--- a/interfaces/index.ts
+++ b/interfaces/index.ts
@@ -1,4 +1,4 @@
-export type IRuleType = 'string' | 'number' | 'date'
+export type IRuleType = 'string' | 'number' | 'date' | 'custom'
 
 export enum RuleStringOptions {
   contains = 'contains',
@@ -32,11 +32,15 @@ export enum RuleOperator {
 }
 
 export type IRoles = RuleStringOptions | RuleNumberOptions | RuleDateOptions
+
+export type IRuleFilter<T = any> = (datum: T) => boolean
+
 export interface IRule {
-  field: string
-  term?: any
-  role: IRoles
   type: IRuleType
   operator: RuleOperator
+  field?: string
+  term?: any
+  role?: IRoles
   caseSensitive?: boolean
+  filter?: IRuleFilter
 }
diff --git a/src/index.ts b/src/index.ts
index 62ad513..2777c09 100644
--- a/src/index.ts
+++ b/src/index.ts
@@ -3,6 +3,7 @@ import { IRule, RuleOperator } from '../interfaces'
 import { NumberProcessor } from './utils/number'
 import { hashCode } from './utils/hash'
 import { DateProcessor } from './utils/dates'
+import { omit } from './utils/helpers/objects'
 class SearchEngine {
   private shouldHave: any[] = []
   private mustHave: any[] = []
@@ -17,7 +18,7 @@ class SearchEngine {
     this.mustHave = collectionToBeStored
   }
 
-  search(queries: IRule[]) {
+  public search(queries: IRule[]) {
     const query = {
       '@or': queries.filter((item) => item.operator === RuleOperator.OR),
       '@and': queries.filter((item) => item.operator === RuleOperator.AND),
@@ -51,20 +52,28 @@ class SearchEngine {
   }
 
   private someDataIsValid(queryCurrent: IRule, data: Record<string, string>) {
+    const field = queryCurrent.field || ''
     switch (queryCurrent.type) {
       case 'string':
         return new StringProcessor(queryCurrent?.term || null, queryCurrent.role).compareWith(
-          data[queryCurrent.field],
+          data[field],
           queryCurrent.caseSensitive || false,
         )
       case 'number':
         return new NumberProcessor(queryCurrent?.term || null, queryCurrent.role).compareWith(
-          data[queryCurrent.field],
+          data[field],
         )
       case 'date':
         return new DateProcessor(queryCurrent?.term || null, queryCurrent.role).compareWith(
-          data[queryCurrent.field],
+          data[field],
         )
+      case 'custom':
+        if (queryCurrent.filter && typeof queryCurrent.filter === 'function') {
+          const datum = omit(data, ['fs_uuid'])
+
+          return queryCurrent.filter(datum)
+        }
+        throw new Error('[flexysearch]: Custom filter not valid')
       default:
         throw new Error('[flexysearch]: Processor not found')
     }
diff --git a/src/tests/custom.test.ts b/src/tests/custom.test.ts
new file mode 100644
index 0000000..65cac71
--- /dev/null
+++ b/src/tests/custom.test.ts
@@ -0,0 +1,47 @@
+import SearchEngine from '..'
+import { RuleOperator } from '../../interfaces'
+import collection from '../../__mocks__/movies.json'
+
+interface IMovie {
+  id: number
+  title: string
+  year: number
+}
+
+describe('Should match strings', () => {
+  it('[String]: Should cause exception', () => {
+    const results = () =>
+      new SearchEngine(collection).search([
+        {
+          type: 'custom',
+          operator: RuleOperator.AND,
+        },
+      ])
+
+    expect(results).toThrow('[flexysearch]: Custom filter not valid')
+  })
+  it('[String]: Should cause exception', () => {
+    const results = new SearchEngine(collection).search([
+      {
+        type: 'custom',
+        operator: RuleOperator.AND,
+        filter: (datum: IMovie) => {
+          return datum.year === 2009
+        },
+      },
+    ])
+
+    expect(results).toStrictEqual([
+      {
+        id: 1,
+        title: 'Film 1',
+        year: 2009,
+      },
+      {
+        id: 7,
+        title: 'Film 7',
+        year: 2009,
+      },
+    ])
+  })
+})
diff --git a/src/utils/dates.ts b/src/utils/dates.ts
index 515c879..a37b412 100644
--- a/src/utils/dates.ts
+++ b/src/utils/dates.ts
@@ -1,12 +1,12 @@
 import { RuleDateOptions } from '../../interfaces/index'
 import { IRoles } from '../../interfaces'
-import { VALIDATE_DATE_REGEXP } from './regexp'
+import { VALIDATE_DATE_REGEXP } from './helpers/regexp'
 
 export class DateProcessor {
   private term: string
   private role: IRoles
 
-  constructor(value: string, role: IRoles) {
+  constructor(value: string, role?: IRoles) {
     this.term = value
     this.role = role as RuleDateOptions
   }
diff --git a/src/utils/helpers/objects.ts b/src/utils/helpers/objects.ts
new file mode 100644
index 0000000..8affca6
--- /dev/null
+++ b/src/utils/helpers/objects.ts
@@ -0,0 +1,15 @@
+export const omit = (object: Record<string, any>, keys: Array<string>): Record<string, any> => {
+  if (!object) return {}
+  try {
+    const payload = Object.entries(object).filter(([key]) => !keys.includes(key))
+    const data: { [key: string]: any } = {}
+
+    payload.forEach((item) => {
+      const [key, value] = item
+      data[key] = value
+    })
+    return data
+  } catch {
+    return {}
+  }
+}
diff --git a/src/utils/regexp/index.ts b/src/utils/helpers/regexp.ts
similarity index 100%
rename from src/utils/regexp/index.ts
rename to src/utils/helpers/regexp.ts
diff --git a/src/utils/number.ts b/src/utils/number.ts
index a935184..1f677d3 100644
--- a/src/utils/number.ts
+++ b/src/utils/number.ts
@@ -5,7 +5,7 @@ export class NumberProcessor {
   private term: number
   private role: IRoles
 
-  constructor(value: number, role: IRoles) {
+  constructor(value: number, role?: IRoles) {
     this.term = Number(value)
     this.role = role as RuleNumberOptions
   }
diff --git a/src/utils/strings.ts b/src/utils/strings.ts
index 73cbb1b..cd703db 100644
--- a/src/utils/strings.ts
+++ b/src/utils/strings.ts
@@ -5,7 +5,7 @@ export class StringProcessor {
   private caseSensitive = false
   private role: IRoles
 
-  constructor(value: string, role: IRoles) {
+  constructor(value: string, role?: IRoles) {
     this.term = value
     this.role = role as RuleStringOptions
   }