eVS, e-invoice checking for Vietnamese companies

The public site and invoice flows of a SaaS that collects incoming e-invoices and checks them with the tax authority.

Livechecked 21/10

Client: Pratek
Role: Built features front to back, at Pratek
Period: 02/2025 → 06/2026
Proof: 1 claim
Stack: Next.js · TypeScript · Tailwind CSS · next-intl · React Hook Form · Zod · Docusaurus · Java

1ProblemAccountants checked every incoming invoice by hand each tax period.
2BuildJava APIs called only through Next.js server routes, validated XML upload, SEO and two languages.
3ResultLive at evsapp.vn with a free tier and a partner program.

✓P1
eVS is live

Problem

Accountants in Vietnam check every incoming e-invoice against the tax authority by hand each tax period. Invoices from suppliers that stopped trading, or that were cancelled after filing, turn into tax risk.

Build

SSR and SSG pages with metadata, sitemap, canonical URLs and JSON-LD. Java APIs for invoice checking and contact flows that the browser reaches only through Next.js server routes, so credentials stay on the server.

XML uploads are validated with React Hook Form and Zod in the browser and again on the server. The site has two languages through next-intl, and the documentation runs on Docusaurus.

Result

eVS runs in production at evsapp.vn, with a free tier and a partner program P1.

Limits

eVS is a Pratek product. The pricing and marketing copy on the live site are not mine.

My part

The public site, the invoice upload and checking flows, and the APIs behind them.

Proof of delivery · NLV-25-EVS