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01 Background
I'm an American developer and operator based in Bali, working GMT+8 with deliberate overlap into Australian hours. I run SSTIEM — a custom creative boutique focused on building systems, workflows, automations, and applications. I'm not an agency, and I'm not a Fiverr freelancer. With me you get my time, my projects, and my curation.
From 2014 to 2018 I worked with NASA in data systems and field research for agricultural and soil programs — growing from field technician into technical manager. I deployed environmental monitoring hardware, pulled soil samples in the field, ran the analysis back at the lab, and helped turn raw field telemetry into research-grade data for white papers. When a measurement has to be right, the process around it matters more than any one clever part — that lesson has shaped everything I've built since.
After NASA, I went on to direct operations for residential housing in Seattle — running logistics and vendor budgets across 300+ tenants. From there I started businesses of my own, built some, sold some, and moved into service businesses, platforms, and media companies in Bali. That's where SSTIEM began.
SSTIEM has been alive for three years, and it started because I kept watching good businesses lose time to software that wasn't custom, wasn't navigable, and wasn't friendly. So I started building my own: infrastructures, operating systems, and multi-tenant applications that fit the way a business actually runs.
We started with business owners, and now we offer everything we've built across all kinds of verticals — websites, applications, automations, and the protocols and systems underneath them. The seven platforms in the live-work section below are all live, all open to inspection, right now.
References available on request, including client contacts who can speak to delivery and communication directly.
02 Why this project
It's a gym — so here's my case in the language of one. Three muscles, all trained, all showing up for this build.
Knowledge is a muscle, and I've put my reps in — from NASA labs, to running operations, to three years of building software systems every single day. When I read your spec I didn't just see a feature list; I saw the whole machine — where the data lives, where the pressure points are, what has to hold when a thousand people show up at once. You put together one of the best briefs I've ever been sent. It deserves a builder who trained for it.
Health and fitness mean a lot to me — they're a real part of my life, not a market vertical. I believe in what you're building: the goal, the timeline, the spec you already put together. That's exactly why my rate is competitive. Not because I lack knowledge or ability, and not because I undervalue myself — but because I believe in this project, my talents are aligned with it, and I want to be the one who builds it.
Will is a muscle you practice, and mine gets trained daily — long builds finished without anyone standing over me, and years of operations before that where the deadline carried someone else's livelihood. A fixed February date doesn't scare me. It's the kind of finish line I train for.
03 What you're hiring
Not just a front-end or back-end developer — a full-stack builder with years of management, communication, and operations behind the code.
With me you aren't hiring labour by the ticket. I read a spec for its contradictions before they become change requests. I write the process documentation as the system takes shape, not after. And I'll tell you when something in the brief won't work as written — before it costs you a month.
That's the operator half. The developer half means nothing gets lost in translation: the person who decides how the member cap gets enforced is the same person who builds it, tests it under load, and then explains it to you in plain language.
And I'm looking at this as the start of a relationship, not a single transaction. You have future locations. You'll have future ideas. What you get with me is stewardship — a full package for growth, and a vendor you can call on at any point. That's exactly why this first build gets my full attention.
04 Live work · open any of these in a browser
I call them BOS builds, and they all carry the same four layers — which is exactly the four layers your brief describes. Across them I've worked custom databases, Postgres, SQLite and Supabase, multi-tenant payment infrastructure, hosting and security, and engines running large datasets concurrently.
The engine underneath: data model, orchestration between third-party systems, and the rules that decide what a user is allowed to do. Never hardcoded — always settings an operator can change.
The staff-facing side. ATX Notary runs ten modules — appointments, clients, messages, finance, compliance, automation, SEO, audit logs, users. That is the shape of your admin portal.
The customer-facing account: bookings, history, documents, payments, support threads. Your member dashboard is this layer.
Built so a second location, brand, or business runs on the same architecture with different settings — I've run tenant infrastructure past 10,000 tenants. Your Section 5 requires exactly this: the presales engine reused at the next site.
Systems where the underlying engineering problem is the same as yours, even without a live link to click.
05 The build, in plain terms
Reading your brief carefully, the member app is actually the smallest piece — the window. The real build is everything behind it: the backend where every rule lives, the glue that keeps GymMaster, HubSpot, and Stripe perfectly in sync, and the engine that makes the hard moments — a launch rush, a membership handoff — behave. Here it is in plain terms, month by month.
What you asked forHard caps that can't oversell, even in a launch rush.
What it really meansWhen the presale opens, hundreds of people will hit "join" in the same moment. If the app only checks "is there room?" on the screen, two people can both see yes — and you've sold slot 1,001. The only referee that can't be fooled is the database itself: it processes one claim at a time, holds a slot while someone finishes checkout, and quietly releases it if they walk away. That's exactly where I'll enforce it — and the cap numbers live as settings you can change, not code, because you told me this engine runs again at the next site.
What you asked forA member hands their membership to someone else, cleanly.
What it really meansThis is a baton pass, and the whole job is defining the rules of the pass: who's allowed to give, who's allowed to receive, the exact moment the handoff becomes final, and what happens if either person drops it mid-pass. Every step gets written down as it happens — a full audit trail — and the member count stays exact the entire way through, so a transfer never opens or eats a slot by accident. The incoming member sets up their own payment method, which was your own recommendation and the right one: it keeps billing history clean.
What you asked forPhone opens the door; QR covers the gaps.
What it really meansThe main path is simple: phone near the door, member taps, the app tells GymMaster's door system to open. That path needs internet at the door — which is exactly why your rotating QR fallback is the right call for dead spots. The part I'll pressure-test hardest is the handoff between the two, because 5am at a locked door is the moment a member judges the entire app.
What you asked forMy recommendation on native vs. cross-platform — you left it open.
What it really meansMy recommendation is cross-platform: one shared codebase compiled for both stores — against a fixed February date it means the business logic gets built once, not twice. The specific framework gets locked per spec, in week one, with you, in writing. And if any single piece — like the Bluetooth behaviour at the door — turns out to need native code, that piece goes native. The build serves the spec, not a framework preference.
What you asked forAustralian hosting, and my provider recommendation.
What it really meansYour members' health waivers and personal data stay on Australian soil, full stop — and the door responds fast because the server is close. Test and live environments stay fully separated, each with their own GymMaster, HubSpot, and Stripe configurations, exactly as your brief lays out. My recommendation is AWS's Sydney region — the most mature Australian region, with a managed database that gives the row-level locking your caps depend on as a first-class feature, and queueing services that fit the GymMaster, HubSpot, and Stripe webhook traffic naturally.
What you asked forA security and concurrency review of the caps, payments, and transfer flow.
What it really meansBefore launch, someone who isn't me tries to break the most sensitive parts — the caps under load, the money, the transfer. You asked for this in the brief and it's the right instinct. I already have my reviewer in mind and will name them on request. They stay external, because a builder marking their own homework isn't a review.
Your specification runs seventeen sections. Here is where each one lands in this build.
| Your section | How it's covered |
|---|---|
| 1. Architecture | Confirmed as written — GymMaster, HubSpot, and Stripe stay the engines; I build the orchestration and member-facing layer on top. Figma treated as developer-ready and honoured, not reinterpreted. |
| 2. GymMaster | Two-way lifecycle sync, weekly billing reflected not recalculated, v3 door-trigger for access, Gatekeeper for the QR fallback, and native booking surfaced with my tier validation in front of it. Month 1 and 4. |
| 3. HubSpot | Lifecycle stages, waitlist capture, and trial-abuse dedup against the CRM record — treated as your identity system, not a marketing tool. Custom Code Actions for real-time sync. Month 1–2. |
| 4. Stripe | Weekly subscriptions across all tiers, the $34.95 access pass, PT add-ons and casual packs, Apple/Google Pay, failed-payment retry, webhooks for every state change, idempotent checkout. Month 2. |
| 5. Presales engine | Uncapped waitlist, simultaneous single-use tokens, 1,000-slot cap held at the database with checkout-hold reservation, auto-invalidation, 15%-for-life fallback — shipped as per-location config for future sites. Month 3. |
| 6. Capacity management | 1,700 ceiling, real-time tracking, slot released the instant a member exits, signup blocked before payment at capacity with waitlist routing, staff and instructors excluded. Same transaction safety as §5. Month 3. |
| 7. Booking windows | 7 / 3 / 24-hour advance windows by account type for the recovery zone — all three values backend-configurable, no code change to adjust. Month 4. |
| 8. Trial logic | 7-day trial with backend on/off toggle, one per person for life, dedup against HubSpot's record rather than local data, automatic transition at 12:01am on day 8, admin intercept on duplicates. Month 2. |
| 9. Referrals | In-app portal with unique URL per member, conversion tracked on paid signup, one month free to the referrer, referring member's ID pushed to the GymMaster profile field. Month 4. |
| 10. Feedback module | Built as a ticketing system, not a contact form — media upload to object storage, flagged to management with account context, and a real reply thread back to the member with notification. Month 5. |
| 11. Google reviews | Rating captured in-app first, synced out to the Business listing, with 4- and 5-star ratings automatically applying 7 days free to the next billing cycle. Month 4. |
| 12. Membership transfer | Full state machine: eligibility, named recipient, identity verification, new payment method for the incoming member, GymMaster profile transfer rather than cancel-and-rejoin, slot held accurately throughout, defined point of no return, mid-transfer failure handling, notifications both sides, complete audit trail. Month 5. |
| 13. Dashboard & push | Live tenure, check-in totals and referral counts; a reusable backend-configurable onboarding walkthrough triggered on first login, dismissible and revisitable; FCM push for classes, billing, capacity openings, and lifecycle events. Month 5. |
| 14. Apps & web portal | iOS and Android from your Figma, plus the browser dashboard sharing one backend with full account management — gate access stays native-only. Store submission with review buffer. Months 5–6. |
| 15. Non-functional | Separated staging and production each with their own GymMaster/HubSpot/Stripe configs, Australian hosting, CI/CD, independent security and concurrency review of §5/§6/§12, unit + integration + end-to-end testing including simulated concurrent presale load, encryption in transit and at rest. Throughout, hardened in month 6. |
| 16. Timeline | Confirmed achievable. Mid-August start, delivery end of February, with store review cycles absorbed in the buffer. Section 08 names the one dependency that could move it. |
| 17. What you asked for | Tech approach and cloud provider recommended with reasoning above; total cost in section 07; assumptions and dependencies in sections 07 and 08; timeline confirmed. All five answered. |
06 Where SSTIEM sits
Published Australian agency rates for this class of work. Across the roughly 1,000 hours this build needs, that lands between AUD $150,000 and $300,000 — four to eight people, some of them junior, and an account manager between you and the work.
You talk to me. I build. I own the deliverables. I bring special attention to detail because I'm creative and I care — and I have close collaborators I can pull in when it genuinely helps. For this level of single-person ownership, the rate usually runs much higher.
Cheap, fast, priced per task — no opinion on your architecture, no stake in your outcome, and gone at handover.
I'm offering a competitive rate because I like this project and I'm confident in what I can deliver — not because this is bargain work.
07 Compensation
That's the full scope in your brief, delivered inside your fixed window — roughly a thousand hours, full-time, across six months. The arithmetic is open on purpose: the price is built from the scope, not guessed at it.
Roughly 1,000 hours at an effective US$42 an hour. Billed as a simple monthly retainer, so you never bet the budget on trust — you pay for the month in front of you, and you watch it get built.
No 50% deposit, no invoice ambush — the first month starts it, and every month after that you've already seen what the last one produced. Weekly written updates, a weekly call if you want one, and a live build you can open any time. If a phase ever genuinely needs an extra pair of hands, we talk first — nothing changes without your sign-off. We can also set payment benchmarks together if that suits you better.
If you have developers you'd like on this, or you'd rather bring me in as a technical lead inside your team, that's a different scope and a fair conversation — happy to have it.
Tooling, VPS and hosting, and third-party subscriptions — passed through at cost once the stack is locked, agreed before anything is spent.
Apple and Google developer accounts, store fees, and the work of getting the app live in both stores — a small, defined extra scope we agree together.
Ongoing maintenance and technical stewardship — a retainer conversation for later, once you've seen how I work.
For context: at published Australian agency rates of AUD $150–330 an hour, this scope prices out well past AUD $150,000. What modern tooling made faster is the typing — I pass that saving to you. The judgment, the architecture, and the accountability stay senior, and stay mine.
08 Questions — yours and mine
Is February achievable? Yes. Mid-August start, delivery by end of February, with the App Store and Play review cycles absorbed inside the buffer. I have shipped live Stripe subscription billing, worked closed third-party booking APIs of GymMaster's class, and built inside HubSpot with custom code actions — the three integrations this build stands on.
The total number: US$42,000 — roughly 1,000 hours across six months, billed at US$7,000 a month, with tooling, hosting, and store costs passed through at cost, per section 07.
What I need at kickoff: the Figma files, and sandbox credentials for GymMaster, HubSpot, and Stripe. A late handoff on those is the only thing that moves the date.
What lands in February: both apps submitted, the web dashboard live, the backend running, full documentation, credentials, and the codebase — yours.
Design coverage — how many Figma screens are in the handoff, and is the admin dashboard designed too, or only the member app?
GymMaster — is the full API documentation and a sandbox available, and are the door-trigger and membership-transfer endpoints confirmed working, not just documented?
HubSpot & Stripe — are the workflows and subscription products already configured, and who owns maintaining the HubSpot side after launch?
Launch load — how big do you expect the waitlist to be at the presale moment? It changes how hard I load-test the rush.
The Apple Developer account — published under your account or mine? I'd recommend yours, so the business owns its own listing; I'll run it either way.
Your team — is anyone on your side joining the build, or is this a clean solo engagement?
After launch — support, warranty window, and ongoing stewardship: talk now, or once the build has spoken for itself?
References — I can arrange calls on four of these builds: Hillside Cleaning, NEOS / Nuanu, ATX Notary, and Tymeline Studios. Say the word and I'll make the introductions.
Thomas Tyler Hill · SSTIEM
Bali, Indonesia · GMT+8 · sstiem.pro@gmail.com