diff --git a/package-lock.json b/package-lock.json
index 3f02893..74a4190 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -1,12 +1,12 @@
 {
   "name": "gas-fire",
-  "version": "2.0.0",
+  "version": "1.1.3",
   "lockfileVersion": 2,
   "requires": true,
   "packages": {
     "": {
       "name": "gas-fire",
-      "version": "2.0.0",
+      "version": "1.1.3",
       "license": "MIT",
       "workspaces": [
         "client",
diff --git a/package.json b/package.json
index 4b94208..d44d440 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "gas-fire",
-  "version": "1.1.1",
+  "version": "1.1.3",
   "author": "Melle Dijkstra",
   "description": "Google App Script utilities to automate the FIRE google sheet",
   "license": "MIT",
diff --git a/src/server/category_detection.ts b/src/server/category-detection/index.ts
similarity index 100%
rename from src/server/category_detection.ts
rename to src/server/category-detection/index.ts
diff --git a/src/server/config.ts b/src/server/config.ts
index d7112ad..fcaef2b 100644
--- a/src/server/config.ts
+++ b/src/server/config.ts
@@ -1,4 +1,4 @@
-import { buildColumn } from './table-utils';
+import { TableUtils, buildColumn } from './table-utils';
 import { Transformers } from './transformers';
 import type { Strategy, StrategyOption, Table } from './types';
 import { n26Cols, raboCols, openbankCols } from './types';
@@ -12,93 +12,95 @@ export const AUTO_FILL_COLUMNS = [
 ];
 
 const defaultAfterImport = [
-  (table: Table) => Utils.autoFillColumns(table, AUTO_FILL_COLUMNS),
+  (table: Table) => TableUtils.autoFillColumns(table, AUTO_FILL_COLUMNS),
 ];
 
 type RootConfig = {
   [key in StrategyOption]: Strategy;
 };
 
+const n26Config: Strategy = {
+  beforeImport: [
+    TableUtils.deleteLastRow,
+    TableUtils.deleteFirstRow,
+    TableUtils.sortByDate(n26Cols.Date),
+  ],
+  columnImportRules: {
+    ref: null,
+    iban: (data) => new Array(data.length).fill(Utils.getBankIban('N26')),
+    date: buildColumn(n26Cols.Date, (val) => new Date(val)),
+    amount: buildColumn(n26Cols.Amount, parseFloat),
+    category: buildColumn(n26Cols.Payee, Transformers.transformCategory),
+    contra_account: buildColumn(n26Cols.Payee, String),
+    label: buildColumn(n26Cols.TransactionType, String),
+    import_date: (data) => new Array(data.length).fill(new Date()),
+    description: buildColumn(n26Cols.PaymentReference, String),
+    contra_iban: buildColumn(n26Cols.AccountNumber, String),
+    currency: buildColumn(n26Cols.ForeignCurrencyType, String),
+  },
+  afterImport: defaultAfterImport,
+};
+
+const rabobankConfig: Strategy = {
+  beforeImport: [
+    TableUtils.deleteLastRow,
+    TableUtils.deleteFirstRow,
+    TableUtils.sortByDate(raboCols.Datum),
+  ],
+  columnImportRules: {
+    ref: buildColumn(raboCols.Volgnr, parseInt),
+    iban: buildColumn(raboCols.Iban, String),
+    date: buildColumn(raboCols.Datum, (val) => new Date(val)),
+    amount: buildColumn(raboCols.Bedrag, Transformers.transformMoney),
+    category: null,
+    contra_account: buildColumn(raboCols.NaamTegenpartij, String),
+    import_date: (data) => new Array(data.length).fill(new Date()),
+    contra_iban: buildColumn(raboCols.Tegenrekening, String),
+    currency: buildColumn(raboCols.Munt, String),
+    description: buildColumn(raboCols.Omschrijving1, String),
+    label: buildColumn(raboCols.Omschrijving2, String),
+  },
+  afterImport: defaultAfterImport,
+};
+
+const openbankConfig: Strategy = {
+  beforeImport: [
+    TableUtils.deleteFirstRow,
+    TableUtils.deleteLastRow,
+    // open bank has some empty columns when importing
+    (table) => TableUtils.deleteColumns(table, [0, 2, 4, 6, 8]),
+  ],
+  columnImportRules: {
+    ref: null,
+    iban: (data) => new Array(data.length).fill(Utils.getBankIban('OPENBANK')),
+    date: buildColumn(openbankCols.Fecha, (val) => {
+      let [day, month, year] = val.split('/');
+      let yearNum = +year;
+      if (year && year.length === 2) {
+        // if year is of length 2 it means it only provides the year since 2000
+        // to fix we add 2000
+        yearNum = +year + 2000;
+      }
+      return new Date(+yearNum, +month - 1, +day);
+    }),
+    amount: buildColumn(openbankCols.Importe, Transformers.transformMoney),
+    category: null,
+    contra_account: null,
+    label: null,
+    description: buildColumn(openbankCols.Concepto, String),
+    import_date: (data) => new Array(data.length).fill(new Date()),
+    contra_iban: null,
+    currency: null,
+  },
+  afterImport: defaultAfterImport,
+};
+
 export class Config {
   static getConfig(): RootConfig {
     return {
-      n26: {
-        beforeImport: [
-          Utils.deleteLastRow,
-          Utils.deleteFirstRow,
-          Utils.sortByDate(n26Cols.Date),
-        ],
-        columnImportRules: {
-          ref: null,
-          iban: (data) => new Array(data.length).fill(Utils.getBankIban('N26')),
-          date: buildColumn(n26Cols.Date, (val) => new Date(val)),
-          amount: buildColumn(n26Cols.Amount, parseFloat),
-          category: buildColumn(n26Cols.Payee, Transformers.transformCategory),
-          contra_account: buildColumn(n26Cols.Payee, String),
-          label: buildColumn(n26Cols.TransactionType, String),
-          import_date: (data) => new Array(data.length).fill(new Date()),
-          description: buildColumn(n26Cols.PaymentReference, String),
-          contra_iban: buildColumn(n26Cols.AccountNumber, String),
-          currency: buildColumn(n26Cols.ForeignCurrencyType, String),
-        },
-        afterImport: defaultAfterImport,
-      },
-      rabobank: {
-        beforeImport: [
-          Utils.deleteLastRow,
-          Utils.deleteFirstRow,
-          Utils.sortByDate(raboCols.Datum),
-        ],
-        columnImportRules: {
-          ref: buildColumn(raboCols.Volgnr, parseInt),
-          iban: buildColumn(raboCols.Iban, String),
-          date: buildColumn(raboCols.Datum, (val) => new Date(val)),
-          amount: buildColumn(raboCols.Bedrag, Transformers.transformMoney),
-          category: null,
-          contra_account: buildColumn(raboCols.NaamTegenpartij, String),
-          import_date: (data) => new Array(data.length).fill(new Date()),
-          contra_iban: buildColumn(raboCols.Tegenrekening, String),
-          currency: buildColumn(raboCols.Munt, String),
-          description: buildColumn(raboCols.Omschrijving1, String),
-          label: buildColumn(raboCols.Omschrijving2, String),
-        },
-        afterImport: defaultAfterImport,
-      },
-      openbank: {
-        beforeImport: [
-          Utils.deleteFirstRow,
-          Utils.deleteLastRow,
-          // open bank has some empty columns when importing
-          (table) => Utils.deleteColumns(table, [0, 2, 4, 6, 8]),
-        ],
-        columnImportRules: {
-          ref: null,
-          iban: (data) =>
-            new Array(data.length).fill(Utils.getBankIban('OPENBANK')),
-          date: buildColumn(openbankCols.Fecha, (val) => {
-            let [day, month, year] = val.split('/');
-            let yearNum = +year;
-            if (year && year.length === 2) {
-              // if year is of length 2 it means it only provides the year since 2000
-              // to fix we add 2000
-              yearNum = +year + 2000;
-            }
-            return new Date(+yearNum, +month - 1, +day);
-          }),
-          amount: buildColumn(
-            openbankCols.Importe,
-            Transformers.transformMoney
-          ),
-          category: null,
-          contra_account: null,
-          label: null,
-          description: buildColumn(openbankCols.Concepto, String),
-          import_date: (data) => new Array(data.length).fill(new Date()),
-          contra_iban: null,
-          currency: null,
-        },
-        afterImport: defaultAfterImport,
-      },
+      n26: n26Config,
+      rabobank: rabobankConfig,
+      openbank: openbankConfig,
     };
   }
 }
diff --git a/src/server/exposed_functions.ts b/src/server/exposed_functions.ts
index 51732f5..545bdc0 100644
--- a/src/server/exposed_functions.ts
+++ b/src/server/exposed_functions.ts
@@ -4,7 +4,7 @@
  * @param xpath simplified xpath as string
  * @customfunction
  */
-function IMPORTJSON(url: string, xpath: string) {
+export function IMPORTJSON(url: string, xpath: string) {
   try {
     // /rates/EUR
     var res = UrlFetchApp.fetch(url);
@@ -90,7 +90,7 @@ function IMPORTJSON(url: string, xpath: string) {
  * @return {string}         The hashed input value.
  * @customfunction
  */
-function MD5(input: string): string {
+export function MD5(input: string): string {
   var txtHash = '';
   var rawHash = Utilities.computeDigest(
     Utilities.DigestAlgorithm.MD5,
diff --git a/src/server/globals.ts b/src/server/globals.ts
new file mode 100644
index 0000000..0cba223
--- /dev/null
+++ b/src/server/globals.ts
@@ -0,0 +1,24 @@
+import { getSheetById } from './utils';
+
+export const fireColumns = [
+  'ref',
+  'iban',
+  'date',
+  'amount',
+  'balance',
+  'contra_account',
+  'description',
+  'satisfaction',
+  'icon',
+  'category',
+  'label',
+  'hours',
+  'contra_iban',
+  'disabled',
+  'currency',
+];
+
+export const SOURCE_SHEET_ID = 1093484485;
+export const FireSpreadsheet = SpreadsheetApp.getActiveSpreadsheet();
+export const sheets = FireSpreadsheet.getSheets();
+export const sourceSheet = getSheetById(SOURCE_SHEET_ID);
diff --git a/src/server/index.ts b/src/server/index.ts
index d97f461..e485bd5 100644
--- a/src/server/index.ts
+++ b/src/server/index.ts
@@ -1,7 +1,8 @@
+// Functions to setup the initial UI
 export { onOpen, fileUploadDialog, openAboutDialog } from './ui';
 
-export {
-  generatePreview,
-  getStrategyOptions,
-  processCSV,
-} from './remote-calls';
+// Remote procedure calls made by the client UI executed on the server
+export { getStrategyOptions, processCSV } from './remote-calls';
+
+// Custom functions that can be used within the Spreadsheet UI
+export { IMPORTJSON, MD5 } from './exposed_functions';
diff --git a/src/server/remote-calls.ts b/src/server/remote-calls.ts
index b88112f..0b2244d 100644
--- a/src/server/remote-calls.ts
+++ b/src/server/remote-calls.ts
@@ -1,10 +1,10 @@
+import { sourceSheet } from './globals';
 import { Config } from './config';
-import { buildNewTableData } from './table-utils';
-import { ServerResponse, Strategy, StrategyOption, Table } from './types';
-import { Utils, sourceSheet } from './utils';
+import { TableUtils, processTableWithImportRules } from './table-utils';
+import { ServerResponse, StrategyOption, Table } from './types';
 
 export function processCSV(
-  input: Table,
+  inputTable: Table,
   importStrategy: StrategyOption
 ): ServerResponse {
   const strategies = Config.getConfig();
@@ -19,12 +19,12 @@ export function processCSV(
 
   if (beforeImport) {
     for (const rule of beforeImport) {
-      input = rule(input);
+      inputTable = rule(inputTable);
     }
   }
 
-  let output = buildNewTableData(input, columnImportRules);
-  Utils.importData(output);
+  let output = processTableWithImportRules(inputTable, columnImportRules);
+  TableUtils.importData(output);
 
   if (afterImport) {
     for (const rule of afterImport) {
@@ -45,10 +45,3 @@ export function processCSV(
 export function getStrategyOptions(): typeof StrategyOption {
   return StrategyOption;
 }
-
-export function generatePreview(
-  data: Table,
-  strategy: StrategyOption
-): { result: Table; newBalance: number } {
-  return { result: data, newBalance: 1240.56 };
-}
diff --git a/src/server/table-utils.ts b/src/server/table-utils.ts
index 410d287..b879f2f 100644
--- a/src/server/table-utils.ts
+++ b/src/server/table-utils.ts
@@ -1,23 +1,5 @@
+import { fireColumns, sourceSheet } from './globals';
 import { ColumnRule, FireColumnRules, InputColumn, Table } from './types';
-import { Utils } from './utils';
-
-export const FireColumns = [
-  'ref',
-  'iban',
-  'date',
-  'amount',
-  'balance',
-  'contra_account',
-  'description',
-  'satisfaction',
-  'icon',
-  'category',
-  'label',
-  'hours',
-  'contra_iban',
-  'disabled',
-  'currency',
-];
 
 export function buildColumn<T>(
   column: InputColumn,
@@ -25,7 +7,7 @@ export function buildColumn<T>(
 ): (data: Table) => T[] {
   return (data: Table): T[] => {
     const rowCount = data.length;
-    const columnTable = Utils.transpose(data); // try to transpose somewhere else
+    const columnTable = TableUtils.transpose(data); // try to transpose somewhere else
     if (columnTable[column] !== undefined) {
       return columnTable[column].map((val) => transformer(val));
     } else {
@@ -34,13 +16,19 @@ export function buildColumn<T>(
   };
 }
 
-export function buildNewTableData(
+/**
+ * What the heck does this function do?
+ * @param input
+ * @param columnImportRules
+ * @returns
+ */
+export function processTableWithImportRules(
   input: Table,
   columnImportRules: FireColumnRules
 ) {
   let output: Table = [];
   const rowCount = input.length;
-  for (const columnName of FireColumns) {
+  for (const columnName of fireColumns) {
     if (!(columnName in columnImportRules) || !columnImportRules[columnName]) {
       output.push(new Array(rowCount));
       continue;
@@ -49,13 +37,112 @@ export function buildNewTableData(
     let column: any[];
     try {
       column = colRule(input);
-      column = Utils.ensureLength(column, rowCount);
+      column = TableUtils.ensureLength(column, rowCount);
     } catch (e) {
       Logger.log(e);
       column = new Array(rowCount);
     }
     output.push(column);
   }
-  output = Utils.transpose(output); // flip columns to rows
+  output = TableUtils.transpose(output); // flip columns to rows
   return output;
 }
+
+export class TableUtils {
+  /**
+   * Imports data in structure of a table into the source sheet
+   * @param {Table} data the data to be imported into the source sheet
+   */
+  static importData(data: Table) {
+    const rowCount = data.length;
+    const colCount = data[0].length;
+    console.log(`importing data (rows: ${rowCount}, cols: ${colCount})`);
+    sourceSheet
+      ?.insertRowsBefore(2, rowCount)
+      .getRange(2, 1, rowCount, colCount)
+      .setValues(data as Table);
+  }
+
+  /**
+   * @see https://github.com/ramda/ramda/blob/v0.27.0/source/transpose.js
+   */
+  static transpose<T>(outerlist: T[][]): T[][] {
+    let i = 0;
+    let result = [];
+    while (i < outerlist.length) {
+      let innerlist = outerlist[i];
+      let j = 0;
+      while (j < innerlist.length) {
+        if (typeof result[j] === 'undefined') {
+          result[j] = [];
+        }
+        result[j].push(innerlist[j]);
+        j += 1;
+      }
+      i += 1;
+    }
+    return result;
+  }
+
+  static deleteFirstRow(data: Table): Table {
+    data.shift();
+    return data;
+  }
+
+  static deleteLastRow(data: Table): Table {
+    data.pop();
+    return data;
+  }
+
+  static sortByDate(dateColumn: number) {
+    return (data: Table) => {
+      data
+        .sort(
+          (row1, row2) =>
+            new Date(row1[dateColumn]).getUTCDate() -
+            new Date(row2[dateColumn]).getUTCDate()
+        )
+        .reverse();
+      return data;
+    };
+  }
+
+  static deleteColumns(table: Table, colIndices: number[]): Table {
+    // we want to have the indices sorted backwards to prevent shifting of elements
+    // while traversing the array
+    const sortedIndices = colIndices.sort().reverse();
+    // tranpose the table so we are working with columns first instead of rows
+    let transposedTable = this.transpose(table);
+    Logger.log('transposed');
+    Logger.log(transposedTable);
+    // delIndex is the column index to delete in the table
+    for (const delIndex of sortedIndices) {
+      if (typeof transposedTable[delIndex] !== 'undefined') {
+        transposedTable.splice(delIndex, 1);
+      }
+    }
+    // transpose again back to rows first
+    return this.transpose(transposedTable);
+  }
+
+  static autoFillColumns(data: Table, columns: number[]) {
+    for (const column of columns) {
+      const rowCount = data.length;
+      const sourceRange = sourceSheet?.getRange(2 + rowCount, column);
+      const destinationRange = sourceSheet?.getRange(2, column, rowCount + 1); // + 1 because sourceRange needs to be included
+      if (destinationRange) {
+        sourceRange?.autoFill(
+          destinationRange,
+          SpreadsheetApp.AutoFillSeries.DEFAULT_SERIES
+        );
+      }
+    }
+  }
+
+  static ensureLength(arr: unknown[], length: number) {
+    if (arr.length < length) {
+      arr = arr.fill(null, arr.length, length - 1);
+    }
+    return arr;
+  }
+}
diff --git a/src/server/transformers.ts b/src/server/transformers.ts
index 7bacd78..2eee30e 100644
--- a/src/server/transformers.ts
+++ b/src/server/transformers.ts
@@ -1,4 +1,4 @@
-import { detectCategoryByTextAnalysis } from './category_detection';
+import { detectCategoryByTextAnalysis } from './category-detection';
 
 export class Transformers {
   static transformMoney(value: string, decimalSeparator: string = ','): number {
diff --git a/src/server/utils.ts b/src/server/utils.ts
index 54a83d6..cb87d0c 100644
--- a/src/server/utils.ts
+++ b/src/server/utils.ts
@@ -1,9 +1,4 @@
-import { Table, InputColumn } from './types';
-
-export const SOURCE_SHEET_ID = 1093484485;
-
-const FireSpreadsheet = SpreadsheetApp.getActiveSpreadsheet();
-const sheets = FireSpreadsheet.getSheets();
+import { FireSpreadsheet, sheets } from './globals';
 
 export function getSheetById(
   id: number
@@ -11,102 +6,7 @@ export function getSheetById(
   return sheets.find((sheet) => sheet.getSheetId() === id);
 }
 
-export const sourceSheet = getSheetById(SOURCE_SHEET_ID);
-
 export class Utils {
-  /**
-   * @see https://github.com/ramda/ramda/blob/v0.27.0/source/transpose.js
-   */
-  static transpose<T>(outerlist: T[][]): T[][] {
-    let i = 0;
-    let result = [];
-    while (i < outerlist.length) {
-      let innerlist = outerlist[i];
-      let j = 0;
-      while (j < innerlist.length) {
-        if (typeof result[j] === 'undefined') {
-          result[j] = [];
-        }
-        result[j].push(innerlist[j]);
-        j += 1;
-      }
-      i += 1;
-    }
-    return result;
-  }
-
-  static importData(data: Table) {
-    const rowCount = data.length;
-    const colCount = data[0].length;
-    Logger.log(`importing data (rows: ${rowCount}, cols: ${colCount})`);
-    sourceSheet
-      ?.insertRowsBefore(2, rowCount)
-      .getRange(2, 1, rowCount, colCount)
-      .setValues(data as Table);
-  }
-
-  static autoFillColumns(data: Table, columns: number[]) {
-    for (const column of columns) {
-      const rowCount = data.length;
-      const sourceRange = sourceSheet?.getRange(2 + rowCount, column);
-      const destinationRange = sourceSheet?.getRange(2, column, rowCount + 1); // + 1 because sourceRange needs to be included
-      if (destinationRange) {
-        sourceRange?.autoFill(
-          destinationRange,
-          SpreadsheetApp.AutoFillSeries.DEFAULT_SERIES
-        );
-      }
-    }
-  }
-
-  static ensureLength(arr: any[], length: number) {
-    if (arr.length < length) {
-      arr = arr.fill(null, arr.length, length - 1);
-    }
-    return arr;
-  }
-
-  static deleteFirstRow(data: Table): Table {
-    data.shift();
-    return data;
-  }
-
-  static deleteLastRow(data: Table): Table {
-    data.pop();
-    return data;
-  }
-
-  static deleteColumns(table: Table, colIndices: number[]): Table {
-    // we want to have the indices sorted backwards to prevent shifting of elements
-    // while traversing the array
-    const sortedIndices = colIndices.sort().reverse();
-    // tranpose the table so we are working with columns first instead of rows
-    let transposedTable = this.transpose(table);
-    Logger.log('transposed');
-    Logger.log(transposedTable);
-    // delIndex is the column index to delete in the table
-    for (const delIndex of sortedIndices) {
-      if (typeof transposedTable[delIndex] !== 'undefined') {
-        transposedTable.splice(delIndex, 1);
-      }
-    }
-    // transpose again back to rows first
-    return this.transpose(transposedTable);
-  }
-
-  static sortByDate(dateColumn: InputColumn) {
-    return (data: Table) => {
-      data
-        .sort(
-          (row1, row2) =>
-            new Date(row1[dateColumn]).getUTCDate() -
-            new Date(row2[dateColumn]).getUTCDate()
-        )
-        .reverse();
-      return data;
-    };
-  }
-
   static getBankAccounts(): Record<string, string> {
     // this range contains the ibans only
     const ibans = FireSpreadsheet.getRangeByName('accounts');