hi, i'm junjie (jj).
I build things that (hopefully) work — full stack and AI, currently at Didero in NYC.
This is my grasshut: part portfolio, part notebook, eventually a whole brain. Poke around.
growing here
- braindumpvoice-first personal knowledge OS — my second brain, in progress · digging the foundation
- talkerinos →thoughts, rambles, and the occasional tutorial
- app hub →small experiments and tools, in various states of done
- qol+hand-drawn quality-of-life dashboard — calendar, lists, life admin · growing quietly
work so far
Didero
Member of Technical StaffAug 2025 — nowBuilding AI agents for procurement, shipping product end-to-end.
Enjoying New York City while I'm at it.
AI Singapore
AI Engineer InternMay — Aug 2025SEA-LION v4 post-training: multi-agent reward pipelines, RLHF (PPO, GRPO, DAPO).
Built a code-judging agent that improved evaluation accuracy by 30%.
SUSS
Software Engineer InternJan — May 2025RAG systems with DSPy and AI scrapers for dynamic sites.
Evaluated AI tools for classroom teaching.
on the way
plots i've marked out but haven't planted yet.
notes garden
public pieces of the braindump vault
calendar →
what i'm up to — just sprouted, take a look
workflows
little automations running my life
photo roll
film & phone shots worth keeping