diff --git a/src/modules/expenses/controllers/expense.controller.ts b/src/modules/expenses/controllers/expense.controller.ts
index 2359b7a..bb37634 100644
--- a/src/modules/expenses/controllers/expense.controller.ts
+++ b/src/modules/expenses/controllers/expense.controller.ts
@@ -1,10 +1,21 @@
-import { Controller } from "@nestjs/common";
+import { Body, Controller, Param, ParseIntPipe, Post } from "@nestjs/common";
 import { PrismaService } from "src/prisma/prisma.service";
+import { ExpenseDto } from "../dtos/expense.dto";
+import { CreateResult, ExpenseUpsertService } from "../services/expense-upsert.service";
 
 
 @Controller('expense')
 export class ExpenseController {
-    constructor(private readonly prisma: PrismaService){}
+    constructor(
+        private readonly prisma: PrismaService,
+        private readonly upsert_service: ExpenseUpsertService,
+    ){}
 
-    
+
+    // @Post(':timesheet_id')
+    // create(
+    // @Param('timesheet_id', ParseIntPipe) timesheet_id: number,
+    // @Body() dto: ExpenseDto): Promise<CreateResult>{
+    //     return this.upsert_service.createExpense(timesheet_id, dto);
+    // }
 }
\ No newline at end of file
diff --git a/src/modules/expenses/dtos/expense.dto.ts b/src/modules/expenses/dtos/expense.dto.ts
index e69de29..51cc174 100644
--- a/src/modules/expenses/dtos/expense.dto.ts
+++ b/src/modules/expenses/dtos/expense.dto.ts
@@ -0,0 +1,14 @@
+import { IsBoolean, IsInt, IsOptional, IsString, MaxLength } from "class-validator";
+
+export class ExpenseDto {
+    @IsInt()    bank_code_id!: number;
+    @IsInt()    timesheet_id!: number;
+    @IsString() @IsOptional() attachment?: string;
+    
+    @IsString()  date!: string;
+    @IsInt()     @IsOptional()   amount?:  number;
+    @IsInt()     @IsOptional()   mileage?: number;
+    @IsString()  @MaxLength(280) comment!: string;
+    @IsBoolean() is_approved!:  boolean;
+    @IsString()  @MaxLength(280)  @IsOptional() supervisor_comment?: string
+}
\ No newline at end of file
diff --git a/src/modules/expenses/dtos/get-expense.dto.ts b/src/modules/expenses/dtos/get-expense.dto.ts
index e69de29..6c3056e 100644
--- a/src/modules/expenses/dtos/get-expense.dto.ts
+++ b/src/modules/expenses/dtos/get-expense.dto.ts
@@ -0,0 +1,11 @@
+export class GetExpenseDto {
+    timesheet_id: number;
+    bank_code_id: number;
+    attachment?:  string;
+    date:         string;
+    comment:      string;
+    mileage?:     number;
+    amount?:      number;
+    supervisor_comment?: string;
+    is_approved:  boolean;
+}
\ No newline at end of file
diff --git a/src/modules/expenses/dtos/update-expense.dto.ts b/src/modules/expenses/dtos/update-expense.dto.ts
index e69de29..fc709bb 100644
--- a/src/modules/expenses/dtos/update-expense.dto.ts
+++ b/src/modules/expenses/dtos/update-expense.dto.ts
@@ -0,0 +1,6 @@
+import { OmitType, PartialType } from "@nestjs/swagger";
+import { ExpenseDto } from "./expense.dto";
+
+export class updateExpenseDto extends PartialType (
+    OmitType(ExpenseDto, ['is_approved', 'timesheet_id'] as const)
+){}
\ No newline at end of file
diff --git a/src/modules/expenses/helpers/expenses-date-time-helpers.ts b/src/modules/expenses/helpers/expenses-date-time-helpers.ts
new file mode 100644
index 0000000..ce14e69
--- /dev/null
+++ b/src/modules/expenses/helpers/expenses-date-time-helpers.ts
@@ -0,0 +1,3 @@
+export const  toDateFromString = (ymd: string): Date => {
+  return new Date(`${ymd}T00:00:00:000Z`); 
+}
\ No newline at end of file
diff --git a/src/modules/expenses/services/expense-upsert.service.ts b/src/modules/expenses/services/expense-upsert.service.ts
new file mode 100644
index 0000000..5e47a1e
--- /dev/null
+++ b/src/modules/expenses/services/expense-upsert.service.ts
@@ -0,0 +1,46 @@
+import { Injectable } from "@nestjs/common";
+import { PrismaService } from "src/prisma/prisma.service";
+import { GetExpenseDto } from "../dtos/get-expense.dto";
+import { updateExpenseDto } from "../dtos/update-expense.dto";
+import { ExpenseDto } from "../dtos/expense.dto";
+import { toDateFromString } from "../helpers/expenses-date-time-helpers";
+
+type Normalized = { date: Date; comment: string; supervisor_comment: string; };
+
+export type CreateResult  = { ok: true;   data: GetExpenseDto } | { ok: false; error: any };
+export type UpdatePayload = { id: number; dto: updateExpenseDto };
+export type UpdateResult  = { ok: true;   id: number; data: GetExpenseDto } | { ok: false; id: number; error: any };
+export type DeleteResult  = { ok: true;   id: number; } | { ok: false; id: number; error: any };
+
+type NormedOk  = { dto: GetExpenseDto; normed: Normalized };
+type NormedErr = { error: any };
+
+@Injectable()
+export class ExpenseUpsertService {
+    constructor(private readonly prisma: PrismaService){}
+
+    //_________________________________________________________________
+    //                              CREATE
+    //_________________________________________________________________
+    //normalized frontend data to match DB
+    async createExpense(timesheet_id: number, dto: ExpenseDto){
+        const normed_expense = this.normalizeExpenseDto(dto)
+        
+
+    }
+
+    //_________________________________________________________________
+    //                         LOCAL HELPERS
+    //_________________________________________________________________
+    private normalizeExpenseDto(dto: ExpenseDto): Normalized {
+        const date    = toDateFromString(dto.date);
+        const comment = this.truncate280(dto.comment);
+        const supervisor_comment = this.truncate280(dto.supervisor_comment? dto.supervisor_comment : '');
+        return { date, comment, supervisor_comment };
+    }
+
+    //makes sure that a string cannot exceed 280 chars
+    private truncate280 = (input: string): string => {
+        return input.length > 280 ? input.slice(0, 280) : input;
+    }
+}
\ No newline at end of file
diff --git a/src/modules/shifts/services/shifts-upsert.service.ts b/src/modules/shifts/services/shifts-upsert.service.ts
index 9ed8457..e63380b 100644
--- a/src/modules/shifts/services/shifts-upsert.service.ts
+++ b/src/modules/shifts/services/shifts-upsert.service.ts
@@ -333,7 +333,7 @@ export class ShiftsUpsertService {
     //_________________________________________________________________
     //                              DELETE
     //_________________________________________________________________
-    //finds shift using shit_ids
+    //finds shifts using shit_ids
     //recalc overtime shifts after delete
     //blocs deletion if approved
 	    async deleteShift(shift_id: number) {