Back in service only when safe
Marking a defect fixed returns the vehicle to service only when no other open or in-progress critical defect remains on it.
Back to Work
Rebuild case study / Fleet pre-start checks
PreStart: a fleet check app rebuilt from Bubble® as code you own.
PreStart started as an app built on Bubble. The studio rebuilt it as code on Cloudflare Workers from a written spec of the original, kept its pages and rules, tightened the workflows that needed it, and released it as a free Lite edition and a paid Pro edition.
- What it does
- Daily vehicle checks and a workshop defect queue
- First built on
- Bubble
- Rebuilt on
- Cloudflare Workers, D1 and R2
- Editions
- Lite (free, MIT licence) and Pro ($149 USD, paid once)
In short
PreStart is a daily vehicle pre-start check and defect workflow for small fleets, first built by Red Center Studio on Bubble and published as a Bubble template. The rebuild is one Cloudflare Worker with a D1 database, private R2 photo storage and Better Auth sign-in, written in TypeScript, with every permission checked on the server and tests that run in the Workers runtime. PreStart Lite is free and open source, and PreStart Pro is $149 USD, paid once. Both run in the owner's own Cloudflare account.
Before
What it was on Bubble.
PreStart was first built on Bubble, where it is also published as an app template. Drivers submitted daily checks with odometer readings and photos, defects were logged by severity, and workshop staff worked the defect queue and managed vehicles.
The rebuild started from a written spec taken from the Bubble app's test version. It maps the app's six data types, eleven pages, privacy rules and backend workflows to their code equivalents, and lists every place where the code version should behave differently.
| In the Bubble app | In the code version |
|---|---|
| Six data types | D1 tables designed from them. Each check now stores one row per checklist item instead of a single failed items text field, so history shows exactly what was ticked. |
| Privacy rules and page redirects | One permission module on the server, checked on every request and never only by hiding buttons. |
| Built-in users and a password reset page | Better Auth on D1: email and password sign-in, email confirmation and password reset. |
| A Claim this app button | The first account on a fresh install becomes the Admin, new sign-ups wait for approval, and the last admin cannot be removed. |
| A shared menu element | One top menu on every signed-in page, showing only the links a role allows. |
| A backend workflow that wiped the demo | A demo mode with a nightly reset by Cron Trigger. |
Tightened in the rebuild
Workflow rules made stricter.
The written spec noted where the original workflows could be stricter. Each is built into the code version, whose tests cover every permission rule and business rule.
Saved together or not at all
A check, its results, its defect and the vehicle update are saved in one database batch on the server.
Odometer readings checked
A reading lower than the last one needs confirming and is flagged in history.
Off road means off road
Checks on off-road vehicles are rejected on the server, not only hidden from the list.
One settings record
Business settings are created once by a migration, so they cannot be duplicated.
Report a problem anyway
A driver can raise a defect even when every checklist item passed.
Now
What PreStart does today.
Pass, Fail or N/A on a phone
Drivers pick the vehicle, enter the odometer and mark each item. A failed item asks what is wrong, how serious it is, and takes up to 3 photos.
Clear next steps
Minor: safe to drive, the workshop is told. Major: do not drive until a supervisor or the workshop says it is safe. Critical: the vehicle goes off road.
Ready-made checklists
Car, ute or 4WD, truck, trailer, forklift and plant, grouped into sections like Tyres, Lights and Brakes.
Defect queue
Critical faults first. The workshop starts work, adds notes and marks things fixed. Picking a vehicle shows its known faults.
Fleet and history
Odometer, rego and service due dates, and every check filtered by vehicle, driver, date and result.
Roles and private photos
Driver, Workshop and Admin. Photos are shrunk on the phone, stored in a private R2 bucket and shown only to people allowed to see them.
Pro adds QR code stickers per vehicle, instant email on critical faults, rego and service reminders, CSV export and printable check reports, checks that save offline and send when signal returns, region settings, checklists per vehicle type, a driver declaration with signature, engine hours and fuel, a Today board, a missed-check email, an optional location stamp, and defect assignment with fix-by dates.
How it is built
The stack.
- Runtime
- One Cloudflare Worker serves the pages, forms and photos.
- Framework
- Hono with server-rendered JSX, TypeScript in strict mode, Tailwind CSS, and Zod validation on the server.
- Database
- Cloudflare D1 with Drizzle ORM and migrations applied on deploy.
- Files
- A private Cloudflare R2 bucket. Photos are streamed by the Worker after a permission check.
- Sign-in
- Better Auth on D1, with a rate limit on sign-in attempts.
- Email and schedules
- Cloudflare Email Sending, and Cron Triggers for the demo reset and, in Pro, the reminders and missed-check emails.
Tests
Unit tests run inside the real Workers runtime against a real local D1 database and cover every permission rule and every business rule. End-to-end tests drive a real browser at desktop and phone sizes, and the Pro tests include offline checks.
For the owner
What changed for the owner.
- The app runs in the owner's own Cloudflare account. Checks, defects and settings sit in their D1 database and photos in their private R2 bucket, and Red Center Studio does not host their copy.
- There is no monthly fee to Red Center Studio. Lite is free under the MIT licence, and Pro is $149 USD, paid once. Cloudflare's free plans for Workers, D1 and R2 cover a typical small fleet.
- The code is readable and theirs to change: every caption lives in one labels file and every permission rule in one module.
- Pro is built on the open-source Lite edition, and fixes to Lite are merged into Pro.
Start free: PreStart Lite on GitHub. Daily vehicle pre-start checks and a defect workflow for small fleets, on Cloudflare Workers. MIT licence.
Your app
Want your own app rebuilt as code you own?
The same move is a service: your app ported to your own Cloudflare account, with a fixed quote before work starts.
No-Code App Porting
Your app is built on Bubble® or a similar no-code platform and it has outgrown it, or you want to own the code. The studio ports it to your own Cloudflare account, or moves only the heavy parts and leaves the rest where it is. Every port starts with a paid assessment and a fixed quote.
- Price
- From $2,999 USD
- Timeline
- 6 to 12 weeks for a full port
App Rescue and Move to Cloudflare
Built an app with Lovable, Bolt, Emergent, v0 or Replit, or on Bubble? Start with an audit (or a triage for a Bubble app), rescue it where it is, or move it to Cloudflare as code you own. A lead machine only works when sign-in works, search engines can find the pages and the data is protected, so those come first.
- Price
- From $299 USD, in three steps
- Timeline
- Audit usually 3 to 5 business days; rescue and move timelines are set in your quote
Custom Platform and SaaS Builds
Web apps, SaaS products, client portals, marketplaces, booking systems and internal tools. Senior, agency-quality work, delivered faster and at lower cost than an agency, by the person who builds it.
- Price
- From $2,500 USD
- Timeline
- 4 to 12 weeks