Build in public #5 — Shipped 3 APIs this week: Invoice, QR Code, PDF-to-JSON | $20 MRR

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Forgelab — Build in Public: Week of May 8, 2026

Three APIs shipped this week. Here's what's live, what the numbers look like, and what's coming next.

What shipped this week

1. Invoice Generator API

Turn JSON into a professional PDF invoice in one POST request. Supports 3 templates (modern, classic, minimal), 15 currencies, and line item calculations with tax.

curl -X POST https://forgelab.africa/api/invoice/generate \
  -H "X-API-Key: fliv_your_key" \
  -H "Content-Type: application/json" \
  -d '{"company":"Acme Corp","client":"Big Client","currency":"USD","items":[{"description":"API Integration","quantity":1,"price":1200.00}]}'

Response: a ready-to-send PDF invoice.

Templates: modern, classic, minimal. Currencies: USD, EUR, GBP, NGN, KES, INR, BRL, JPY, and 7 more.

2. QR Code API

Generate QR codes in PNG, SVG, or base64. Decode QR codes from uploaded images.

# Generate
curl -X POST https://forgelab.africa/api/qr/generate \
  -H "X-API-Key: flqr_your_key" \
  -H "Content-Type: application/json" \
  -d '{"data":"https://forgelab.africa","format":"png"}'

# Decode
curl -X POST https://forgelab.africa/api/qr/decode \
  -H "X-API-Key: flqr_your_key" \
  -F "file=@qrcode.png"

Useful for event tickets, product labels, app deep links.

3. PDF-to-JSON API

Extract structured text from any PDF. Returns pages array, text content, word count, and document metadata.

curl -X POST https://forgelab.africa/api/pdf-json/extract \
  -H "X-API-Key: flpj_your_key" \
  -F "file=@invoice.pdf"

Useful for parsing invoices automatically, reading bank statements, or turning any document into structured data.

By the numbers (honest)

Metric	Today
APIs live	5
Paying customers	2
MRR	$20/month
Waitlist signups	15
API keys issued	4

MRR is small. But both customers are paying — not on a free trial, not me testing my own product. That distinction matters at week 3.

Goal: $25,000 in 6 months.

Stack

Node.js 20 + Express + SQLite on a single Linux server behind Nginx. Stripe handles billing via webhooks. No Kubernetes. No managed cloud. SQLite handles 5 APIs fine at this scale — when we hit 10k users the plan is PostgreSQL. Until then, near-zero ops overhead is a feature.

All 5 APIs live

PDF API — merge, split, compress, convert
Image API — resize, compress, watermark, convert
PDF-to-JSON API — extract structured data from PDFs
QR Code API — generate and decode QR codes
Invoice API — generate PDF invoices from JSON

One account, one API key format, same pricing tiers across all products at forgelab.africa.

Free browser tools (SEO strategy)

Three free browser tools:

Merge PDF — forgelab.africa/merge-pdf
Compress PDF — forgelab.africa/compress-pdf
Split PDF — forgelab.africa/split-pdf

5 free uses per month, no card required. They run on the Forgelab PDF API internally. Free tools drive Google traffic — API drives revenue. Zero ad spend.