I built an API to generate PDF invoices from JSON

Hacker News

Hi HN, I'm Daniel. I built a simple and straightforward API: you POST a JSON payload with your invoice data, and it returns a secure, presigned URL to a generated PDF. The goal is to make invoicing a single, reliable API call so you can get back to your main product. I also used this as a personal challenge to move away from my old LAMP stack background and build something new with Python/FastAPI, Next.js, and a serverless architecture on GCP and AWS. For the HN community, I've set up a promo code: HEYHN100 If you sign up, you can redeem it in your dashboard for 100 free credits (on top of the 10 you get by default). The credits don't expire. I'm here to answer any questions and would genuinely appreciate any feedback or technical critiques you have. Thanks for checking it out.

Visit product View on Hacker NewsJul 29, 2025

Share card

Actual performance

1points

Did not reach leaderboard

Launch Intel predictions

Analyze your own launch →

Indie HackersFits the IH revenue-focused audience · Missing: supports, reddit linkedin, podcasting

70%70% predicted probability of success on Indie Hackers, based on ML models trained on real launch data.

best fitHighest predicted score across all platforms for this description.

Product HuntOn track for Day 1 leaderboard · Strong signals: new, single, code · Missing: mac, agents, macos

58%58% predicted probability of success on Product Hunt, based on ML models trained on real launch data.

Hacker NewsMay not resonate with HN audience · Strong signals: io · Missing: https docs, excited, just released

43%43% predicted probability of success on Hacker News, based on ML models trained on real launch data.

nativeThis product was originally launched on this platform.

TrustMRRLess likely to generate early MRR · Strong signals: personal, way · Missing: mobile apps, ios, entrepreneurs

42%42% predicted probability of success on TrustMRR, based on ML models trained on real launch data.

AppSumoMay struggle as an AppSumo deal · Missing: plus, platform, intuitive

32%32% predicted probability of success on AppSumo, based on ML models trained on real launch data.

Acquire.comPre-revenue stage for this audience · Missing: arr, mrr, revenue

16%16% predicted probability of success on Acquire.com, based on ML models trained on real launch data.

BetaListMay not resonate with beta-testers · Missing: web3, chat, crypto

0%0% predicted probability of success on BetaList, based on ML models trained on real launch data.

Correct prediction on native model

Similar products

Pdfcpu – Generate PDF from JSON46%Launch Intel prediction score: how likely this product is to succeed on its source platform, based on its name, tagline, and description.

Pdfcpu – Generate PDF from JSON

Hacker News2

Thelawin – Generate EU e-invoices from JSON38%Launch Intel prediction score: how likely this product is to succeed on its source platform, based on its name, tagline, and description.

Thelawin – Generate EU e-invoices from JSON

Hacker News1

An Unofficial JSON API for the Onion's Horoscopes51%Launch Intel prediction score: how likely this product is to succeed on its source platform, based on its name, tagline, and description.

An Unofficial JSON API for the Onion's Horoscopes

Hacker News1

JAPICAM – JSON API Caller and Redux Middleware42%Launch Intel prediction score: how likely this product is to succeed on its source platform, based on its name, tagline, and description.

JAPICAM – JSON API Caller and Redux Middleware

Hacker News1

JSON to RestFul API Pastebin52%Launch Intel prediction score: how likely this product is to succeed on its source platform, based on its name, tagline, and description.

JSON to RestFul API Pastebin

Hacker News2

RemoteModel, JSON API to NSObject DSL for RubyMotion62%Launch Intel prediction score: how likely this product is to succeed on its source platform, based on its name, tagline, and description.

RemoteModel, JSON API to NSObject DSL for RubyMotion

Hacker News5

I gave my API a JSON homepage36%Launch Intel prediction score: how likely this product is to succeed on its source platform, based on its name, tagline, and description.

I gave my API a JSON homepage

Hacker News2

RadioParadise JSON API54%Launch Intel prediction score: how likely this product is to succeed on its source platform, based on its name, tagline, and description.

RadioParadise JSON API

Hacker News4

JSON-to-Go, Built with Go and QML53%Launch Intel prediction score: how likely this product is to succeed on its source platform, based on its name, tagline, and description.

JSON-to-Go, Built with Go and QML

Hacker News4

DocAPI22%Launch Intel prediction score: how likely this product is to succeed on its source platform, based on its name, tagline, and description.

Extract invoices & PDFs into JSON with one API call

Indie Hackers1ai

Browse all products Analyze your launch