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03 / 08 · Full-stack, SaaS · 2025

SpeakSpring

Scenario-based language practice, powered by AI.

My role
Built the entire backend and later contributed to frontend development, working across API design, AI integration, data management, and user-facing features.
Year
2025
Context
Team project
Stack
  • TypeScript
  • Next.js
  • React
  • NestJS
  • PostgreSQL

01 / The problem

The overview

A language-learning platform built around AI-powered scenario conversations, including everyday situations such as ordering food, job interviews, and travel.

  • Designed and implemented backend APIs using NestJS, PostgreSQL, and TypeORM.
  • Implemented authentication using JWT and Passport.js.
  • Integrated OpenAI for AI-powered scenario conversations and learner progress tracking.
  • Contributed to frontend development using Next.js and TypeScript, connecting user-facing features to backend APIs.
SpeakSpring app
fig. 3SpeakSpring

Stack

  • TypeScript
  • Next.js
  • React
  • NestJS
  • PostgreSQL
  • TypeORM
  • JWT
  • Passport.js
  • OpenRouter API
  • Cloudinary