title: "Why we built RailSlot v2" date: 2026-05-23 excerpt: "A clean rebuild of European Railway Capacity Intelligence — zero legacy debt, API-first, 27 networks." author: "Erkin Zhusanbayev"

Why we built RailSlot v2

RailSlot v1 proved the concept: operators want a unified view of European rail capacity. But v1 accumulated workarounds — hydration hacks, mock-as-default data paths, and a monolith that was hard to test.

v2 principles

Clean architecture. Domain logic uses immutable dataclasses, never ORM objects. Every service has tests before merge.

API-first. Every dashboard feature maps to a documented REST endpoint. The UI is a client, not the source of truth.

Real topology. PostGIS geometry from OSM for 27 networks. RC-SPP routing with ETCS braking — not straight-line estimates.

Modern frontend. Turborepo monorepo: static marketing site at railslot.io, SSR app at app.railslot.io, shared design system.

What ships today

Public route calculation, capacity calendar, marketplace skeleton, and multi-country live train feeds where APIs are open. Payoneer for marketplace settlement (not Stripe). Railway backend, Netlify frontend, Supabase Postgres.

What is next

Auth UI, billing, analytics — Phases C through E. If you operate freight or passenger services across EU corridors, join the pilot.