Hello

I build backend systems where data, cloud infrastructure, and intelligent tools meet.

I am Jiajun Wang, a University of Illinois Urbana-Champaign student studying Statistics with a Computer Science minor. My work sits around distributed services, real-time analytics, and practical AI tooling, from LLM-powered internal agents to cloud orchestration systems and event-driven dashboards.

Recently, I have worked on LLM analytics workflows at ByteDance, Java/Spring Boot router orchestration at AWS, and data science projects that turn product and social metrics into decisions. I enjoy building systems that are measurable, maintainable, and pleasant for other engineers to use.

LLM Agent
REST / GraphQL
Kafka
Redis
PostgreSQL
AWS

Tool calling, event streams, indexed storage, and cloud automation in one workflow.

Updates

News

  • Started my first full-time software engineering role after graduation.
  • Published a blog archive converted from LinkedIn posts on engineering, job search, immigration, family, and building in public.
  • Built LLM-powered internal analytics workflows at ByteDance (TikTok) with DouBao, LangChain, Go, Node.js, and GraphQL.
  • Graduated from the University of Illinois Urbana-Champaign with a B.S. in Statistics and a minor in Computer Science.
  • Completed an AWS software engineering internship focused on Java/Spring Boot services, EventBridge scheduling, Lambda, ECS, and DynamoDB.
  • Used Python analysis and visualization to improve social campaign decisions during a data science internship at Aleoga.

Focus

Technical Interests

Backend Infrastructure

Distributed services, API design, router orchestration, service lifecycle metadata, and test automation.

Real-Time Data Systems

Event processing, WebSocket delivery, Redis pub/sub, Kafka streaming, and indexed analytical storage.

AI-Powered Tools

LLM agents, tool-calling workflows, natural language data access, LangChain, and analytics automation.

Cloud & DevOps

AWS, Docker, Kubernetes, CI/CD pipelines, GitHub Actions, Jenkins, and production cleanup automation.

Work

Industry Experience

ByteDance (TikTok)

Software Engineering Intern

Go | Node.js | LLM | DouBao | LangChain | GraphQL

  • Developed an LLM-powered internal analytics agent with tool-calling workflows for 300+ internal users.
  • Built backend REST APIs integrating enterprise data sources for real-time automated dashboard generation.
  • Reduced response time by 30% and operational costs by 50% through backend optimization and workflow tuning.
Amazon Web Services

Software Engineering Intern

Java | Spring Boot | EventBridge | Lambda | ECS | DynamoDB

  • Engineered a distributed router orchestration service replacing manual lab router testing workflows.
  • Designed REST APIs for provisioning and retrieving emulated routers on demand through automated CI/CD pipelines.
  • Persisted router lifecycle metadata in DynamoDB, streamlining test setup and saving 30+ minutes per workflow.
Aleoga

Data Scientist Intern

Python | Matplotlib | Seaborn | Data Analysis

  • Analyzed Instagram, Facebook, and Twitter engagement metrics to identify growth trends and campaign opportunities.
  • Built Python visualizations for interaction quality and advertising effectiveness across social platforms.
  • Supported a 25% active-user increase, 18% advertising ROI improvement, and 12% marketing cost reduction.

Builds

Selected Projects

PushResume

AI Tools

Resume review and parsing web application for helping candidates improve applications with clearer feedback and faster iteration.

AI | Resume Parsing | Web Application | Product

Open project

Real-Time Analytics Dashboard

Systems

Flask and React dashboard processing 100K+ daily events with WebSocket updates, Redis pub/sub, and PostgreSQL aggregation.

Python | Flask | React | Redis | PostgreSQL | Docker | Kubernetes

Open project

EventStream Platform

Streaming

Scalable event-driven platform exposing GraphQL APIs over Kafka streams, MongoDB metadata, and automated CI/CD deployment.

Java | Spring Boot | Kafka | MongoDB | GraphQL | Jenkins

Professor Ratings App

Mobile

Android application for UIUC students to search, view, rate, and comment on professor profiles with secure REST APIs.

Java | SQL | REST API | Android

Media Talent Analysis

NLP

Python NLP pipeline analyzing 1K+ job postings to extract skill gaps between media industry needs and university training.

Python | NLP | Data Analysis | Preprocessing

Background

Education & Skills

University of Illinois Urbana-Champaign

B.S. in Statistics, Minor in Computer Science

GPA: 3.8/4.0. Coursework includes Distributed Systems, Cloud Infrastructure, Algorithms, Database Management, Software Engineering, Machine Learning, and Computer Networks.

Python Java C++ Go SQL JavaScript React Spring Boot Node.js Flask GraphQL LangChain PostgreSQL MongoDB Redis Kafka AWS Docker Kubernetes PyTorch