Javier Cisneros

Full-Stack Software Engineer

I build web applications, from the first technical discussion through production.

Based in Guadalajara, Mexico. I've worked remotely with clients, vendors, and engineering teams across North America.

Work

Some projects and the decisions behind them.

Savings App

A savings application built for more than 10,000 credit union members.

I took the application from technical discovery through production support, working across the client, AWS, and core banking systems.

Authentication and financial data had to move between several systems: our application, the external online banking platform, and the core banking system.

I used Cognito to manage authentication and authorization across the systems connected to the application.

  1. Banno (Online Banking)
  2. Savings App
  3. Internal API
  4. Core Banking System

I built a cross-platform application that promotes savings within online banking while meeting compliance and security requirements across the connected banking systems.

React, TypeScript, Node.js, Python, API Gateway, Cognito, DynamoDB

Embedded Online Banking Integration

A third-party financial product embedded in an existing online banking application.

I led the production launches and managed the authentication workflow between the online banking platform and the embedded application.

The product ran in an iframe, and third-party cookie restrictions broke session creation in some browsers, particularly on Apple devices using WebKit.

I reproduced the failures across browsers, traced them to the cookie dependency, and worked with the vendor to change how sessions were created. I also advised the vendor on authentication for their server-side rendered application.

  1. Online Banking (Q2)
  2. Q2 SDK
  3. Embedded Application
  4. Vendor Application

I integrated the third-party product into the online banking platform and worked around cookie restrictions with a different authentication and session management approach.

Python, HTML, CSS, JavaScript, Server-side Rendering, iframe messaging

Time Reporting Application

A serverless application that replaced manual time reporting for more than 50 employees.

I built the application and moved the team from manual reports to one shared workflow.

Employees worked across time zones, countries, and roles. The team needed a standardized reporting workflow that would reduce reporting time by 66%.

Rather than recreating each department's manual process, we designed one centralized workflow with the stakeholders and employees who would use it. Employees entered time through a weekly interface, while project managers, accounting, and leadership received the level of detail required for approvals, billing, and financial reporting.

  1. Employees
  2. Time App
  3. Project Managers
  4. Managers
  5. Accounting
  6. Billing
  7. Executive Leadership

I created a centralized time-reporting workflow that reduced manual reporting time by 50% at launch and 75% within six months while improving accuracy and reducing errors.

React, Node.js, Cognito, AWS Lambda, API Gateway, RDS, PostgreSQL, AWS

Other work

Smaller production systems I've built or maintained.

Treasury check verification

Integrated a U.S. Treasury API through AWS Lambda to identify mismatched, previously paid, or potentially invalid checks.

Production fee remediation

Built a Python and Lambda process that corrected fee-related records for more than 200 credit union members.

Financial operations tools

Built tools for member maintenance, transaction search, share conversion, and loan workflows that reduced tellers' workloads and manual steps.

Reporting and automation

Maintained scheduled AWS jobs for reports and recurring internal work, using .NET and MySQL connected to Snowflake.

Tools I use

The stack I use most is React, TypeScript, Node.js, and AWS.

Cloud: Lambda, API Gateway, Cognito, DynamoDB, RDS, EventBridge, VPC, serverless architecture

Application: React, Next.js, TypeScript, Node.js, REST APIs

Also: Python, C#/.NET, SQL, IaC, CI/CD

Experience

TekChoice

2024 to present

Full-Stack Software Engineer

Company website

Tianguiza

2023 to 2024

Independent academic project

Visit Tianguiza

Education

B.S. in Software Engineering

Centro de Enseñanza Técnica Industrial (CETI)

Graduated 2024

Certification

AWS Certified Cloud Practitioner

Verify credential

Contact me.

The easiest way to reach me is by email.