You will get a web app that keeps working when the internet does not
Project details
Most web apps quietly assume the connection is there. On a warehouse floor, a delivery route, or a market stall, it is not, and an app that freezes at that exact moment is worse than no app at all, because your people stop trusting it.
I build web apps that keep working with no signal and catch up when it comes back. Not a spinner and a lost form: the action is saved on the device, queued, and sent when the connection returns. Conflicts get handled on purpose instead of one person silently overwriting another.
I built an auction platform this way for a packaging supplier. It runs on cheap phones with bad connections, in production, with real money involved, and 285 automated end-to-end checks. Bids do not disappear because the signal dropped mid-tap.
The part most people skip is the testing. I test with the connection genuinely cut, not simulated in a browser panel, because those two things fail differently.
You get the source code and short notes on how to run, test and deploy it yourself.
I build web apps that keep working with no signal and catch up when it comes back. Not a spinner and a lost form: the action is saved on the device, queued, and sent when the connection returns. Conflicts get handled on purpose instead of one person silently overwriting another.
I built an auction platform this way for a packaging supplier. It runs on cheap phones with bad connections, in production, with real money involved, and 285 automated end-to-end checks. Bids do not disappear because the signal dropped mid-tap.
The part most people skip is the testing. I test with the connection genuinely cut, not simulated in a browser panel, because those two things fail differently.
You get the source code and short notes on how to run, test and deploy it yourself.
Programming Languages
JavaScript, Python, TypeScriptCoding Expertise
Cross Browser & Device Compatibility, Performance OptimizationWhat's included
| Service Tiers |
Starter
$300
|
Standard
$700
|
Advanced
$1,500
|
|---|---|---|---|
| Delivery Time | 7 days | 14 days | 28 days |
Number of Revisions | 1 | 2 | 3 |
Number of Pages | 2 | 5 | 10 |
Design Customization | - | - | - |
Content Upload | - | - | - |
Responsive Design | |||
Source Code |
About Francisco
Full-Stack & AI Engineer | Web Apps, Business Tools, LLM Pipelines
Cuernavaca, Mexico - 2:47 pm local time
The last one is a live auction platform for a packaging supplier in Mexico. It handles real money: WhatsApp-based login, real-time bidding with anti-sniping time extensions, an append-only ledger for every transaction, offline support on bad connections, and 285 end-to-end checks that run on every change. First commit to production in 11 days.
Most of my work has the same shape. A business runs a process by hand, spread across WhatsApp threads and spreadsheets, and it starts breaking as they grow. I build the tool that replaces it: order systems, inventory, quoting, internal dashboards, client portals.
On the AI side I build classification and analysis pipelines on the Anthropic API, with an eval harness and a hand-labelled reference set, so accuracy is measured instead of assumed. The most recent one turns raw customer feedback into structured reports for about a dollar each, and it is covered by 130 tests that run with no network access.
I use AI coding tools as part of my normal workflow, which is why I ship quickly. What I hand over is not a prototype. It runs in production, it has tests, and the deploy is reproducible.
Stack: JavaScript, TypeScript, Python, Node, PocketBase, SQLite and Postgres, offline-capable PWAs, and plain HTML and CSS when a framework would only get in the way. I set up hosting and deployment too, so you get something running, not a folder of code.
You can read my code before you hire me. Everything in my portfolio below is public and open, including the auction platform.
I'm in Mexico, GMT-6, so I overlap with US working hours. I reply within a few hours during the day.
Steps for completing your project
After purchasing the project, send requirements so Francisco can start the project.
Delivery time starts when Francisco receives requirements from you.
Francisco works on your project following the steps below.
Revisions may occur after the delivery date.
Find out what actually has to survive a dropout
Not everything needs to work offline, and pretending otherwise is how these projects get expensive. I identify the two or three actions that must never fail and design around those.
Build it and test it with the network genuinely off
I implement caching, local storage and a queue for pending actions, then test with the connection actually cut, not simulated. A lab test passes; a warehouse basement is the real exam.