Launching on Product Hunt tomorrow: pay-per-use text AI with USDC micropayments (no subscription, 100 free credits)

#showdev #web3 #api #ai

Tomorrow (April 7 at 12:01 AM PDT) I'm launching TextAI API on Product Hunt. Here's the 2-minute story of why I built it and what it does.

The problem: $0.30 kills micropayments

I wanted to build a text processing pipeline — summarize articles, extract keywords, translate content. The usual suspects (OpenAI, AWS Comprehend) either require monthly subscriptions or charge minimum fees that make per-call pricing uneconomical.

The math is brutal: Stripe charges $0.30 + 2.9% per transaction. If your API call costs $0.01, the payment processing fee is 30x the product cost. You're forced to bundle users into monthly plans just to make the economics work.

I wanted a different model: pay exactly for what you call, with no minimum.

The solution: USDC on Solana

Solana transaction fees are ~$0.00025. That makes true micropayments viable at any scale.

TextAI API works like a prepaid SIM card:

Get an API key (instant, no email required)
Top up with USDC credits when you need them
Pay per call — nothing when idle

# Get your key + 100 free credits in one call
curl -X POST https://textai-api.overtek.deno.net/keys/create \
  -H "Content-Type: application/json" \
  -d '{"label":"test"}'
# → {"apiKey":"sk_...","credits":100}

What it does today

Three endpoints, all REST:

Endpoint	What it does	Credits
`POST /summarize`	Condense text to N sentences	10 ($0.01)
`POST /keywords`	Extract top keywords/phrases	5 ($0.005)
`POST /translate`	Translate to 10 languages	15 ($0.015)

1 USDC = 1,000 credits. Process 1,000 documents for ~$5-10 depending on operation mix.

The stack

Built on Deno Deploy + Hono (the fastest JS framework I've tried). SQLite for key/credit storage. The AI engine uses rule-based processing by default with Groq (llama-3.1-8b) when configured — keeps costs near zero at small scale.

The whole thing is ~600 lines of TypeScript.

Try it before the launch

New keys get 100 free demo credits — enough to test all 3 endpoints. No credit card, no email, no account creation.

import requests

# Step 1: get your key
res = requests.post("https://textai-api.overtek.deno.net/keys/create",
    json={"label": "devto-test"})
key = res.json()["apiKey"]

# Step 2: summarize something
result = requests.post("https://textai-api.overtek.deno.net/summarize",
    headers={"X-API-Key": key},
    json={"text": "Your long article here...", "sentences": 3})
print(result.json())