Arya Prasetya, machine learning engineer, Bandung

Clusters found, not guessed

Scroll and the pieces of data above find their clusters, one for each system I have built. The drawing is an illustration and the order is real: the model forms the clusters, a human names them. That is how nearly all of my work begins.

Latency and cost written downEvaluation before launchCode handed over

Arya Prasetya

Machine learning engineer

Bandung, West JavaTaking one new project from April 2026

Eight years, the countable part

8 years years building machine learning systems
14 systems still running in production
180 ms millisecond p95 on the busiest system
31 percent inference cost cut after quantisation

Three systems, written constraint first

Complaint clustering, an insurer

Nine thousand complaints a month across four channels, read one by one. The constraint was not accuracy: the team would not trust a label they could not check.

Clustering with no starting labels, then every cluster named with the team. Reading time fell from six hours to forty minutes a day, and every decision traces to its three nearest examples.

Embeddingsclustering2025

Policy document search, a state enterprise

Twenty two thousand pages of overlapping internal rules. Keyword search failed because each directorate used different terms.

Semantic search with mandatory citations: every answer points at the original page. p95 of 180 milliseconds on hardware they already owned, with no GPU.

Semantic searchon premise2024

Defect detection, a components factory

Twelve thousand parts inspected by eye per shift, with attention falling sharply after two hours.

A small model on a single board computer on the line, 40 milliseconds per part. Escaped defects fell 64 percent, and the operator still decides.

Computer visionedge2023

What I do myself

Models

Embeddings and retrievalText classificationVision for inspectionFine tuning open models

Production

Serving to a latency budgetQuantisation and distillationOutput quality monitoringA and B testing

Tools

PythonPyTorchONNXTensorRTTFLitePostgres with pgvectorDockerKubernetes

What I do not do

Training large models from scratchProjects with no test setSystems with no human in the loop

Those four columns, including the one left uncast

Eight years

  1. 2021 to now

    Freelance engineer

    Independent, Bandung

    Working directly with product teams, usually three to six months per system, until it runs without me.

  2. 2019 to 2021

    Senior engineer

    A logistics company

    Demand forecasting and routing. Here I learned that a model two percent better but hard to explain gets abandoned.

  3. 2017 to 2019

    Data scientist

    A fintech startup

    Risk scoring and fraud detection on data far dirtier than anything university had shown me.

Writing

Education and certification

MSc Informatics

Bandung Institute of Technology

2017

BEng Electrical Engineering

Bandung Institute of Technology

2015

Google Cloud Professional Machine Learning Engineer

Google Cloud

2022

Talk about your project

Describe the problem and the data you already have, not the model you want to use. I reply within a working day with an honest opinion, including when I think the project does not need AI.

Arya Prasetya

Machine learning engineer in Bandung. Systems that are used every day rather than demos, with latency and cost written in the open.

Visit

Bandung, West Java

Replies within one working day

Arya Prasetya. Building AI systems since 2017.