Digital Product Builder

Build and launch zero-cost digital products on Gumroad, itch.io, and DriveThruRPG. Use when creating cover images, asset sheets, or product listings. Generat...

sabroo3-commits@sabroo3-commits

Install

openclaw skills install @sabroo3-commits/digital-product-builder

Digital Product Builder

Build and ship digital products for Gumroad, itch.io, and DriveThruRPG without spending money on image generators or expensive AI models.

Stack: Python Pillow for images ($0) + Groq for copy (~$0.01/product) + Claude main session for orchestration only.

Quick Start

bash

# Check Pillow
python3 -c "from PIL import Image, ImageDraw, ImageFont; print('Pillow ready')" 2>/dev/null || echo "Not installed"

# Install if missing (try each until one works)
pip3 install Pillow
# or: pip install Pillow
# or: python3 -m pip install Pillow

Image Generation — Pillow

Never use the browser tool for image generation. Pillow is faster, crash-free, and requires no login or external service.

Find available fonts (run this first)

python

import os
font_dirs = [
    '/usr/share/fonts',                          # Linux
    '/System/Library/Fonts',                     # macOS
    'C:/Windows/Fonts',                          # Windows
    os.path.expanduser('~/.fonts'),
]
fonts = []
for d in font_dirs:
    if os.path.exists(d):
        for root, _, files in os.walk(d):
            for f in files:
                if f.endswith(('.ttf', '.otf')):
                    fonts.append(os.path.join(root, f))
print('\n'.join(fonts[:20]))

Common font paths (Ubuntu/Debian)

text

/usr/share/fonts/truetype/liberation/LiberationSerif-Bold.ttf
/usr/share/fonts/truetype/liberation/LiberationSans-Bold.ttf
/usr/share/fonts/truetype/dejavu/DejaVuSans-Bold.ttf

Common font paths (macOS)

text

/System/Library/Fonts/Helvetica.ttc
/System/Library/Fonts/Georgia.ttf
/Library/Fonts/Arial.ttf

Safe fallback (always works, no font file needed)

python

font = ImageFont.load_default()  # basic but guaranteed

Platform cover sizes

Platform	Size	Notes
itch.io	630×500px	Required for browse visibility
Gumroad	1280×720px	16:9
DriveThruRPG	900×700px	Landscape or portrait
Social preview (OG/Twitter)	1200×630px	Standard

Cover image boilerplate

python

from PIL import Image, ImageDraw, ImageFont
import os

W, H = 630, 500
SERIF_BOLD = "/usr/share/fonts/truetype/liberation/LiberationSerif-Bold.ttf"

img  = Image.new("RGB", (W, H), (20, 20, 40))
draw = ImageDraw.Draw(img)
font = ImageFont.truetype(SERIF_BOLD, 36)
gold = (201, 168, 76)

# Border
draw.rectangle([10,10,W-10,H-10], outline=gold, width=4)

# Centered title
b = draw.textbbox((0,0), "Your Title", font=font)
draw.text(((W-(b[2]-b[0]))//2, (H-(b[3]-b[1]))//2), "Your Title",
          fill=gold, font=font)

img.save("/path/to/output.png", "PNG", optimize=True)
print(f"Saved ({os.path.getsize('/path/to/output.png')//1024}KB)")

Radial gradient (dark-to-light effect)

python

def lerp(a, b, t):
    return tuple(int(a[i] + (b[i]-a[i])*t) for i in range(3))

center = (230, 180, 80)   # bright centre
edge   = (60,  30,  10)   # dark edge
for step in range(30, 0, -1):
    t  = step / 30
    c  = lerp(center, edge, t)
    r  = int(radius * step / 30)
    draw.ellipse([cx-r, cy-r, cx+r, cy+r], fill=c)

RGBA transparency (for compositing)

python

img  = Image.new("RGBA", (W, H), (20, 20, 40, 255))
draw = ImageDraw.Draw(img, "RGBA")
# ... draw with alpha ...
# Flatten to RGB before saving PNG
bg = Image.new("RGB", (W, H), (20, 20, 40))
bg.paste(img, mask=img.split()[3])
bg.save(out_path, "PNG")

ZIP bundle

python

import zipfile
with zipfile.ZipFile("product.zip", "w", zipfile.ZIP_DEFLATED) as z:
    z.writestr("README.txt", readme_text)
    for fp in file_list:
        z.write(fp, f"subfolder/{os.path.basename(fp)}")

Copy Generation — Groq

API key location: Store your Groq API key in ~/.openclaw/workspace/dashboard/.env as GROQ_API_KEY=your_key_here

Node.js call pattern

javascript

const https = require('https');
const GROQ_KEY = process.env.GROQ_API_KEY;

const body = JSON.stringify({
  model: "llama-3.3-70b-versatile",
  messages: [{ role: "user", content: YOUR_PROMPT }],
  max_tokens: 600,
  temperature: 0.7
});

const req = https.request({
  hostname: 'api.groq.com',
  path: '/openai/v1/chat/completions',
  method: 'POST',
  headers: {
    'Authorization': `Bearer ${GROQ_KEY}`,
    'Content-Type': 'application/json',
    'Content-Length': Buffer.byteLength(body)
  }
}, res => {
  let d = '';
  res.on('data', c => d += c);
  res.on('end', () => console.log(JSON.parse(d).choices[0].message.content));
});
req.write(body);
req.end();

Listing copy prompt template

text

Write a product listing for [PLATFORM]. Plain language. No em dashes.
No filler phrases ("elevate," "perfect for," "streamline your workflow").

Product: [NAME]
What it is: [DESCRIPTION]
Price: [PRICE]
Format: [FILE FORMAT]

Write: title (under 60 chars), tagline (1 sentence), description
(3 short paragraphs), what's included (5 items max), 5 search tags.

De-AI-ify checklist (always run before saving copy)

Remove em dashes — use periods or commas instead
Remove: "elevate," "enhance," "seamlessly," "perfect for," "streamline"
Break up long bullet lists into short paragraphs
If it sounds like a press release, rewrite it

Platform Playbooks

itch.io

New product: Dashboard → Create new project → Downloadable
Cover image: 630×500px required — no cover = invisible in browse
Pricing: fixed price or "pay what you want" with minimum
Upload: ZIP file for multi-file products
Tags: use specific terms (e.g. "ttrpg tokens" not just "game")

Gumroad

New product: Products → New Product → Digital
Cover: 1280×720 recommended
Description editor may require manual paste — automation sometimes blocked
Set Discover category in product settings for marketplace visibility
Configure payout threshold in account settings

DriveThruRPG

Free publisher account at drivethrurpg.com/publishers
Cover: 900×700px
Categories for tokens: Accessories > Tokens/Maps
Revenue: 70% creator / 30% DTRPG
Payout: PayPal, $10 minimum

Common Blockers & Fixes

Blocker	Fix
Bing Image Creator requires MS account	Use Pillow — no external services needed
ideogram.ai / external generators blocked by Cloudflare	Use Pillow
Browser crashes during canvas rendering	Don't use browser for images. Pillow only.
Can't save canvas to file from browser JS	Pillow writes directly to disk
`file://` URLs blocked in browser tool	Serve via `python3 -m http.server PORT`
Gumroad editor blocks automation	Paste listing copy manually
`require is not defined` in browser evaluate	Use exec + node script instead
itch.io "invalid token" on email verify	Safe to ignore if account is already live

Cost Per Product

Item	Tool	Cost
Cover image	Pillow	$0
Asset sheets / bundles	Pillow	$0
Product listing copy	Groq llama-3.3-70b	~$0.01
Orchestration	Claude main session	minimal
Total per product		< $0.05

No sub-agents needed. Do everything inline in the main session.

Example Products Built With This Skill

NPC Dialogue & Quest Text Packs — itch.io, $9
TTRPG Character Token Pack — DriveThruRPG, $7.99
Newsletter Creator Visual Kit — Gumroad, $12

Digital Product Builder

Install

Digital Product Builder

Quick Start

Image Generation — Pillow

Find available fonts (run this first)

Common font paths (Ubuntu/Debian)

Common font paths (macOS)

Safe fallback (always works, no font file needed)

Platform cover sizes

Cover image boilerplate

Radial gradient (dark-to-light effect)

RGBA transparency (for compositing)

ZIP bundle

Copy Generation — Groq

Node.js call pattern

Listing copy prompt template

De-AI-ify checklist (always run before saving copy)

Platform Playbooks

itch.io

Gumroad

DriveThruRPG

Common Blockers & Fixes

Cost Per Product

Example Products Built With This Skill

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