Product Engineer & Fractional CTO

Building software that works. For founders, businesses, and myself.

With 10 years of engineering experience across companies like Traveloka, Airy, and Cosmart, I build my own software products and partner with founders as a product engineer and fractional CTO — spanning applied AI, consumer web & mobile, and operational systems.

Engineering background & scale

TravelokaAiryCosmart
Coloring Page Daily
coloringpagedaily.com
Coloring Page Daily

A daily digital and printable coloring page business with thousands of active users.

01 / Consulting & Advisory

Product Direction, Applied AI & Engineering Leadership

Beyond conventional development, I partner with founders and business operators across the entire lifecycle: scoping MVPs, directing product architecture, deploying applied AI workflows, and scaling engineering teams.

01 / Strategy & Scoping

Product Direction & AI Strategy

Turning business goals into clear technical requirements, scoping MVPs, and identifying where generative AI and automation create genuine operational leverage.

Core deliverables

  • Product roadmapping & MVP scoping
  • Applied AI feasibility & architecture
  • User flow & system design
02 / Hands-On Build

Full-Stack & Applied AI Engineering

End-to-end engineering of customer web platforms, mobile apps, LLM agent workflows, and automated back-office tools that scale reliably.

Core deliverables

  • Production web apps & custom SaaS
  • LLM agents & autonomous pipelines
  • Mobile applications (iOS & Android)
03 / Team & Standards

Engineering Leadership & Modern Tooling

Mentoring developers, vetting technical hires, and embedding modern AI tooling, testing standards, and CI/CD pipelines into team workflows.

Core deliverables

  • Developer hiring & interviewing
  • AI developer tooling & workflow adoption
  • Code reviews, CI/CD & release standards

02 / Engineering Capabilities

What I Deliver & Scale

A comprehensive engineering breadth spanning consumer web products, mobile platforms, enterprise operations, cloud data systems, and hardware.

01

Web platforms & SaaS

Customer-facing products, portals, and custom SaaS from first wireframe to production.

Featured projects

BuildQRMandiri Rejeki AbadiColoring Page DailyPundi EmasForma MetalworksCosmartDevToolsStealth AI CompanyStealth Fintech Company
02

Mobile apps (iOS & Android)

High-performance iOS and Android apps sharing unified APIs and backends with your web products.

Featured projects

CosmartColoring Page DailyMoonlyStealth AI Company
03

Internal tools, operations & ERP

ERP systems, inventory management, quotation engines, and back-office tools that replace manual spreadsheets.

Featured projects

Mandiri Rejeki AbadiForma MetalworksCosmartVertical Indonesia
04

Applied AI & automation

LLM agents and automated data pipelines wired directly into daily operational workflows.

Featured projects

Coloring Page DailyCosmartMandiri Rejeki AbadiDevToolsStealth AI Company
05

Cloud infra & data platforms

High-throughput data pipelines, cloud deployments, and resilient backend systems built for scale.

Featured projects

CosmartMandiri Rejeki AbadiVertical IndonesiaStealth AI CompanyStealth Fintech Company
06

Hardware & embedded systems (IoT)

Custom microcontrollers, embedded firmware, and physical-to-digital hardware products.

Featured projects

Aethercraft Studio

03 / Selected Case Studies

Systems Engineered for Real Businesses

Explore recent projects across web platforms, mobile apps, ERP and operations systems, and AI workflows.

Showing 15 of 15 systems
coloringpagedaily.com
Coloring Page Daily
Applied AIWeb PlatformsMobile Apps
2025-Present

Coloring Page Daily

Free daily printable coloring pages and digital mobile coloring canvas for kids and adults, with automated creative workflows.

build-qr.com
BuildQR
Web Platforms
2026-Present

BuildQR

Branded dynamic QR codes: change where a code points after it is printed, track every scan, and generate codes through an API.

mandirirejeki.co.id
Mandiri Rejeki Abadi
Internal Tools & ERPWeb PlatformsApplied AICloud & Data
2023-Present

Mandiri Rejeki Abadi

A traditional retail business where I run everything technical: the company website, internal ERP, a customer dashboard for enterprise customers, the data platform and IT hardware.

Customer dashboard for
IndomaretAlfamartLawson
cosmart.id
Cosmart
Mobile AppsWeb PlatformsInternal Tools & ERPApplied AICloud & Data
2025-Present

Cosmart

Membership e-commerce platform for bulk buying with high-scale catalog, multi-tier pricing, and synchronized mobile and web applications.

pundiemas.id
Pundi Emas
Web Platforms
2026-Present

Pundi Emas

A newly launched gold retailer going digital. I build and run their website and the online store that comes next.

formametalworks.com
Forma Metalworks
Web PlatformsInternal Tools & ERP
2026-Present

Forma Metalworks

An architectural metal fabricator for facades, screens and custom metalwork. I built their public website and am building the internal ERP that will run their quotations, orders and purchasing.

🔒Stealth AI CompanyConfidential Engagement
Applied AIWeb PlatformsMobile AppsCloud & Data
2026-Present

Stealth AI Company

An early-stage AI company building autonomous multi-agent pipelines and developer intelligence infrastructure.

🔒Stealth Fintech CompanyConfidential Engagement
Web PlatformsCloud & Data
2026-Present

Stealth Fintech Company

A next-generation financial platform providing institutional liquidity, automated clearing, and real-time settlement.

saham.us
Saham.US
Web Platforms
2026-Present

Saham.US

A research platform for US stocks: real-time data, price forecasts, screeners, portfolio tracking and curated picks.

🔒Vertical IndonesiaConfidential Engagement
Cloud & DataInternal Tools & ERP
2025-Present

Vertical Indonesia

Logistics and fulfilment for Indonesian SMEs. I consult on their operations systems, data platform and external integrations.

devtools.devinryanriota.com
DevTools
Applied AIWeb Platforms
2024-Present

DevTools

Small, fast tools for everyday developer work, available on the web and over MCP. An IDE extension and a CLI are planned.

moonly.justanothersimple.app
Moonly
Mobile Apps
2025-Present

Moonly

A mobile app for budgeting and tracking spending, built to make personal financial awareness simple and frictionless.

aethercraft.studio
Aethercraft Studio
Hardware & IoT
2025-Present

Aethercraft Studio

A hardware and design studio making custom fighting-game hitboxes on the RP2040 and bespoke gaming accessories.

justanothersimple.app
Just Another Simple App
Web Platforms
2024-Present

Just Another Simple App

My software studio: focused proprietary products and targeted client applications built with high engineering craft.

🔒Yuk Bantu Bisnis OnlineConfidential Engagement
Internal Tools & ERP
2020-2022

Yuk Bantu Bisnis Online

A digital directory and support initiative that helped 200+ Indonesian small businesses transition online during pandemic lockdowns.

04 / Experience & Archive

Projects & Full-Time Career

A comprehensive history of proprietary products, client software systems, and full-time engineering leadership.

  • 2025-PresentColoring Page DailyA daily digital and printable coloring page business with thousands of active users.
  • 2026-PresentBuildQRA dynamic QR platform with analytics, branding and a developer API.
  • 2023-PresentMandiri Rejeki AbadiOne partner for the website, ERP, customer dashboard, data platform and IT.
  • 2025-PresentCosmartMembership bulk-buying platform with 100k+ mobile app users and high-scale order systems.
  • 2026-PresentPundi EmasHigh-trust digital storefront with live bullion pricing.
  • 2026-PresentForma MetalworksA photo-led public website, plus one ERP to replace spreadsheets and chat threads.
  • 2026-PresentStealth AI CompanyDesigning core agent orchestration architecture and enterprise deployment platform.
  • 2026-PresentStealth Fintech CompanyBuilding high-throughput transaction pipelines, ledger engines, and compliance architecture.
  • 2026-PresentSaham.USInstitutional-grade financial analytics and stock screener.
  • 2025-PresentVertical IndonesiaHigh-throughput logistics data pipeline and carrier integrations.
  • 2024-PresentDevToolsHigh-speed developer utilities with native Model Context Protocol (MCP) integration.
  • 2025-PresentMoonlyFrictionless personal budgeting mobile application with local-first storage.
  • 2025-PresentAethercraft StudioE-Commerce brand and web presence for boutique custom gaming controllers.
  • 2024-PresentJust Another Simple AppProduct studio umbrella shipping targeted web tools and SaaS applications.
  • 2020-2022Yuk Bantu Bisnis OnlineOnboarded and digitized 200+ local retail businesses during emergency restrictions.

Client Access

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Next Step

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Start a projectdevinryanriota@gmail.com