Global App Proposal

Prepared for Hostelling International·June 2026

About us

We create digital solutions for Hospitality Leaders — helping them grow direct bookings and increase guest loyalty.

Founded in 2015, registered in Hong Kong.
Proven track record building & scaling high-traffic websites and mobile apps.
Strong UX / UI foundation with a focus on optimizing conversion.
Highly skilled, specialized team based in the Philippines & Bali.

Selected Work

A selection of recent work relevant to this project.

Selected Work

RydgesWebsite & Booking Engine

Website design & development for a hotel group with 80+ properties.
Booking engine integrated with multiple enterprise PMS sources.

Payments Stripe · Braintree

Visit website

Selected Work

LyLoWebsite & Booking Engine

Website design & development for a modern hostel brand.
Direct-booking engine integrated with the Mews PMS.

Visit website

Selected Work

NightskyWebsite & Booking Experience

Website design & development.
Booking handoff to the Synxis (Sabre) booking engine.

In active development

Selected Work

QT HotelsWebsite & Booking Engine

Website design & development for the QT lifestyle-hotel brand.
Booking engine integrated with enterprise PMS.

Payments Stripe · Braintree

Check booking engine

Selected Work

ThredboWebsite & Booking Engine

Website design & development.
Booking engine integrated with enterprise PMS.

Payments Windcave

Visit website

Selected Work

ThredboMobile App

Design & development, built in React Native.
Used daily by ~50,000 resort visitors.

Selected Work

Event CinemasMobile App

Design & development of the mobile app.
Integration with custom back-end APIs.
UX / UI focused on frictionless ticket and food & beverage booking.
Over 100k monthly active users.

Apple App Store Google Play

Selected Work

EVT StaysLoyalty Platform

Website design & development.
Loyalty system integration.
Custom identity / SSO integration and guest portal build.

Visit website

Understanding your Requirement

Component 01

Global Booking Engine

One embeddable engine, layered over MA systems as the source of truth.

Component 02

Global ID

Federated membership & identity, purchasable inside the booking flow.

Component 03

Global Guest Portal

A unified guest layer over the existing estate — no rip-and-replace.

High-level Approach

Booking Engine

Embeddable widget / HI site

Per-tenant, drops into any MA front end.

Future

AI experiences

MCP server · ChatGPT app · UCP (agentic commerce)

request · clean JSON / REST → ← normalised booking data (JSON)

Core

API Layer

Node.js (TypeScript), serverless / edge. One normalised internal booking structure.

ASSD

OTA XML · HTTPS POST

SiteMinder

OTA XML · polling, re-check at booking

Payment provider

tokenised · via PCI proxy

Global ID

OIDC / OAuth2

Each PMS / channel sits behind its own adapter — new MAs onboard without core changes.
Adapters normalise different protocols (OTA XML, REST, OIDC) into one internal booking structure.
PMS is the system of record; the API layer exposes one clean JSON structure — consumed by the widget today, and potentially by AI agents (ChatGPT App · UCP · OpenClaw, etc) tomorrow.

Security & Compliance considerations

PCI scope minimised — tokenisation, hosted fields.
GDPR consent-driven, with documented deletion.
WCAG accessibility throughout.

Adapter architecture scales MA-by-MA and PMS-by-PMS.
Multi-currency / multi-merchant by design.
API-first foundation.

Delivery Approach

Phase 01

Discovery

Lock scope, the adapter list and the pilot plan.

→

Phase 02

Build · 2-week sprints

Sprints over a 6–8 month period.

→

Phase 03

Rollout of full system

Full delivery across the network. Support & Maintenance.

We start with a dedicated discovery phase to lock scope, adapters and the pilot plan.
We work in two-week sprints, batching development into thin, shippable slices.
Booking engine first — essential features for the pilot, then layer outward.
End to end, the full system is a 6–8 month build.

Commercial Model

Capped time & materials — not-to-exceed, phase by phase

Firm commitment on the booking-engine phase; indicative bands beyond.
Cost drivers: number of adapters, languages, identity scale, payment complexity.
You only pay for work delivered — the cap protects your budget.

PhaseIndicative hours

1 · Technical Discovery (capped)60

2 · UX / UI Design120–140

3 · Booking Engine700–900

Orchestration / adapter layer (Node.js · TypeScript) PMS / channel adapters — ASSD, SiteMinder Payments — multi-currency, PCI proxy Widget front-end + localisation

4 · Global ID250–350

Standards-based identity — OIDC / OAuth2

5 · Guest Portal500–600

Unified guest layer over the existing estate Localisation incl. Arabic (RTL) & simplified Chinese

6 · Testing & QA100–150

7 · PM & Governance (6–8 months)80–120

Total~1,810–2,320 hrs

IndicativeAt US$165/hr — approximately US$300,000–385,000.

The Technical Discovery phase will determine the exact figure within this range.

The Team

Michiel Waaijer

Founder & Delivery Lead

Vikko Taruc

Senior Project Manager

Adrian Cando

Lead Developer & Architect

Rowel Gutierrez

Lead Developer & Architect

Marco Manigbas

Senior QA

Daryl Magos

Senior Designer

Development Team

Web development · UI engineering · DevOps

Our dev team consists of 8 developers, with the ability to scale up.

Senior Team

Michiel Waaijer

Founder & Delivery Lead

Founded Rock Solid Digital in 2015 and will oversee the project. 8+ years in hospitality digital and booking technology, with hands-on oversight of booking-engine and PMS-integration work at multi-property scale.

Vikko Taruc

Senior Project Manager

Leads delivery, client governance and the Agile development process — backlog, cadence and reporting. 6+ years keeping multi-party builds on track and transparent.

Adrian Cando

Lead Developer & Architect

Back-end and systems integration — Node.js / TypeScript, API design. 10+ years on production booking systems. Co-owns the API layer and PMS / payment adapters.

Rowel Gutierrez

Lead Developer & Architect

Deep PMS-integration expertise — Opera, Mews and OHIP-class migrations. 5+ years in hospitality systems. Co-owns the ASSD / SiteMinder adapters.

Daryl Magos

Senior Designer

Leads UX / UI for the widget and guest portal — conversion-focused, mobile-first, WCAG-accessible. 6+ years in booking interfaces.

Marco Manigbas

Senior QA

Owns QA across booking, payment and identity — test strategy, integration harnesses and UAT. 10+ years in software QA.

What our clients say

“

Event Cinemas have partnered with Rock Solid to deliver what is now a best-in-class mobile experience. The team truly care about our digital platform and have always delivered on time and on budget. We look forward to building more amazing experiences with Rock Solid in the coming years.

Andrew TurnerGroup General Manager, Technology & Digital · EVT

“

I've worked with Michiel Waaijer and Rock Solid for nearly a decade, and they've become an indispensable partner — deeply understanding our booking engine, web architecture, and the unique needs of the hotel industry. They've built and maintained a WordPress network supporting over 80 hotels across Australia, New Zealand and Singapore, consistently delivering complex, customized solutions that exceed expectations. Rock Solid makes my work dramatically easier while significantly enhancing our capabilities as a hotel management company — collaborative, flexible, and seamlessly integrated into our workflows.

David TuzaGM Digital — Hotels · EVT

Future Fit

HI's stated direction is AI smart search, AI-driven discovery and AI-agent commerce. We have active capability already in development for other clients.

In development

MCP servers

Model-context endpoints that expose booking capability to AI agents.

In development

ChatGPT app

A conversational front door to the booking experience.

In development

Agentic-commerce protocol

Standards support so agents can transact directly.

Our API-first foundation makes HI ready for agentic commerce.

UI Demo

A working, interactive booking-experience demonstrator, built specifically for HI — illustrating how an immersive, embeddable, hostel-centric booking flow would feel.

Live demo

Thank you

We look forward to working with you and finalising the scope of the project.

Michiel Waaijer

Founder · Rock Solid Digital