Reserve — Rails Apps

Quasar private build

No public demo — it moves real money, so there's no safe login to hand out.

Rails 8.1 · Ruby 4 · solo · in production

Ask me for a walkthrough — the backtest → paper → live promotion funnel is the part I'm proudest of.

A quantitative trading platform that actually trades. It pulls seven market-data feeds, runs studies and backtests, then promotes a strategy through paper trading to live orders on Kraken — with drawdown halts, balance reconciliation, and a daily health digest. Runs in production on a server I manage.

A strict promotion funnel — every strategy earns its way from backtest to paper trading to real capital, or gets cut. No strategy touches money it hasn't proven itself on.
Real safety rails — drawdown halts, slippage caps, idempotent orders, and balance reconciliation that freezes trading the moment the books disagree with the exchange.
Built to be watched — hand-drawn heatmaps, histograms, and parameter-grid sweeps with a live feed — all custom Stimulus, no charting library.
Runs itself — minute-level data on cron, automated backups, a queue watchdog, and a daily health digest to Telegram, on a server I manage end to end.

Sidekiq
MySQL
Kraken API
Hotwire

Golden Hands live demo Open

Rails 7 · Ruby 3.3 · solo · in development

Log in and look around — search by trade and location, open a craftsman's profile, page through a portfolio gallery, leave a review. The whole product is live, not a mock-up.

A bilingual marketplace connecting tradespeople with customers: verified paid profiles with portfolios, search by trade and location, moderated reviews, subscription billing, two-factor admin, and a full admin panel.

Three apps in one — separate customer, craftsman, and admin experiences, each with its own dashboard, onboarding, and permissions.
Serious about security — two-factor admin login with backup codes, a field-level audit log, rate limiting, hardened headers, and a policy check on every action.
Find someone nearby — proximity search that matches a craftsman's service radius, with an interactive region map.
Fully bilingual — every page, email, and category in Czech and English, with payments handled through GoPay subscriptions.

PostgreSQL
GoPay
2FA
geo-search
i18n

Reserve live demo Open

Rails 8 · Ruby 3.3 · solo · in daily use

Log in and book a room — then open the history to watch every change tracked field by field, or the stats for live utilization. It went up in an afternoon; see if you can find a rough edge.

A booking tool for shared office resources — meeting rooms by the slot, a parking spot by the day — with a day calendar, usage stats, and a full audit trail. Built in an afternoon for real colleagues, so it had to be right and polished the first time, not generated until it looked good.

Polished where it counts — a live day calendar with a current-time indicator, a parking-map modal, and an installable mobile (PWA) build.
Nothing gets lost — every booking and edit is recorded in an audit trail with before-and-after values: who changed what, from what, to what.
Fast, but done right — hand-rolled authentication instead of a Devise shortcut, real system tests, and a CI pipeline with security scanning — all inside a few hours' work.
Correct by construction — overlap detection, slot-boundary rules, and per-day parking limits enforced in the model, not left to the UI.

Hotwire
Kamal
CI
system tests