Roast My TechStack #4 · May 7, 2026 · Singapore

Three stacks on the table: a production-style personal LinkedIn analytics pipeline, a caregiver navigation app, and a voice-driven resume. This recap preserves the practical decisions, trade-offs, and questions raised in the room.

Ying Zhao presenting his LinkedIn analytics pipeline at Roast #4

Speaker 01

Ying Zhao presenting his LinkedIn analytics pipeline at Roast #4

Personal LinkedIn Analytics Pipeline

Ying Zhao

A production-style personal analytics pipeline for LinkedIn, built with Databricks in a medallion architecture — and optimized for maximum reach. The roast covered getting the data, ETL done right, retries, and the One Big Table trade-off.

Databricks · Medallion ETL · One Big Table · API · Retries & backoff

LinkedIn GitHub Blog series

01

How To Get The Data

  • API — the first-class route.
  • Scraping — when the API doesn't give you what you need.
  • 3rd party analytics — as a complement or fallback.

02

ETL In Medallion Terms

E → Extract (bronze) · T → Transformation (silver) · L → Load (gold). Databricks is the cloud-based platform that runs the data analytics and AI workloads.

03

Retries And Backoff

To overcome time-out issues, consider retries with backoff — especially for LLM calls and APIs. This prevents a huge bill shock when a provider starts failing in burst.

04

One Big Table Over A Relationship DB

The One Big Table approach beats a relationship database (e.g. Neo4j) for query speed and simplifies data consumption — fewer joins, one place to ask questions of.

Speaker 02

Ee One Lim presenting Care Compass at Roast #4

Care Compass

Ee One Lim

An app that navigates caregivers to the right support resources — a RAG-over-LLM build that raises reliability over raw generation. The roast dug into RAG vs. web search, dynamic model selection, and where to store the knowledge base.

RAG · n8n · Postgres · Dynamic model selector · Web search

LinkedIn GitHub Website

01

RAG Over Plain LLM

If you have a single source of truth, RAG is preferred over a raw LLM — it increases reliability. And if you need the LLM to do a web search, use a dedicated web search tool rather than letting the model guess.

02

Dynamic Model Selection With n8n

Consider an n8n dynamic model selector to choose the best model per use case. n8n reduces LLM usage overall and can switch between using an LLM web search and RAG depending on the query.

03

Store The Knowledge Base In Postgres

Consider Postgres for the RAG store. For cost efficiency, consider other LLMs for this use case — like GPT-5.4 mini or other open-weight models.

Other tools raised: the eval tool in the Claude platform, and Kapso for WhatsApp business workflows.

Speaker 03

Kaleb presenting the Voice Resume at Roast #4

Voice Resume

Kaleb Nim

A voice-driven resume — an AI-voice interview app that lets employers ask anything and get real-time answers. The roast covered voice recognition, budget compute, text-to-speech, and guardrailing AI applications.

ASR · Whisper TTS · Oracle Cloud free tier · Guardrails · persona.md

LinkedIn GitHub Website

01

Speech In, Speech Out

ASR (automatic speech recognition) turns the interview questions into text, and Whisper does the text-to-speech for the answers. The result: employers talk to a resume like it's a candidate.

02

Budget Compute That Lasts

For a budget option, Oracle Cloud's free tier lasts forever: 24GB RAM, 4 CPU, and 10TB egress — plenty for a side project with a video-heavy workload.

03

Guardrails For AI Applications

Always consider guardrails for AI applications, and the simplest way to build them is via a persona.md — encode who the AI is and what it will not do right in the prompt, checked before any answer ships.

Venue sponsor

SGInnovate

SGInnovate

PIC: Arul · Co-hosted with GrowthLab


Event ops volunteers

⏳ Time & Mic Keeper

Esther

LinkedIn

📸 Memories Keeper

Arul

LinkedIn

🎙 Host

Jesse

LinkedIn

🧠 Knowledge Keeper

Han

LinkedIn

Roast My TechStack

Original published recap ↗