SDS Sentinel
Watch a folder, get audit-ready. No spreadsheets, no cloud uploads.
How SDS Sentinel Escaped The Idea Graveyard
A local-first Windows desktop app for EHS managers. It watches a folder for SDS PDFs, extracts GHS hazards, expiry, and SVHC, and gives you one dashboard and a one-click PDF audit report. Everything stays on your machine—SQLite, no cloud. Built for the gap between "Excel + shared drives" and big enterprise SDS platforms.
Genesis Spark
EHS teams drowning in SDS PDFs across folders and inboxes, and manual tracking that falls apart before audit season. I wanted something local-first: watch a folder, extract what inspectors actually care about (GHS, expiry, SVHC), and get one view and one report—no spreadsheets, no sending chemical data to the cloud. Solo micro-SaaS, built to live within a 5–10 h/week maintenance ceiling and a 1k MRR target (four customers at $249/mo).
Core Problem & Insight
The real problem isn't storing SDS—it's fractured tracking and last-minute audit panic. The bet: ingestion and verification can be production-grade (watchdog, parser router, consensus, audit trail) even when the product started as "four fields and a dashboard." Closing the gap meant adding GHS extraction (H/P-codes, signal word, pictograms), storage incompatibility from H-codes, SVHC cross-reference, a compliance score, and a real OSHA-style PDF report—so the app delivers audit-ready output, not just an indexed filing cabinet.
Known Chaos
- Parsing wildly different SDS PDF layouts and pulling GHS Section 2 (H/P-codes, signal word, pictograms) reliably
- Dealing with scanned SDS with no text layer (OCR)
- Keeping scope and maintenance low (solo, 5–10 h/week) while still adding hazard intelligence and a real audit report
Solutions
- Format-specific parsers (e.g. SpatialGHSParser with PyMuPDF) plus a router (parser/cache/OCR); static GHS reference for storage incompatibility
- Docling-based OCR behind a setting; router falls back when text parsing fails; clear "Parsed via OCR" and error feedback
- Strict scope: static SVHC list, no remediation workflows; GHS + SVHC + compliance score + PDF report as the launch set
Arsenal
Python
An interpreted, high-level and general-purpose programming language.
FastAPI
A modern, fast web framework for building APIs with Python based on standard type hints.
Jinja2
A fast, expressive, extensible templating engine for Python, often used for server-rendered HTML.
HTMX
A lightweight library that lets you build dynamic interfaces with simple HTML attributes and server-rendered partials—no heavy JS framework.
SQLite
A lightweight, file-based relational database engine that requires no separate server—ideal for local and embedded apps.
PyMuPDF
A high-performance Python library for reading, rendering, and manipulating PDF documents (fitz).
Docling
A document understanding library that converts PDFs and images into structured content, with OCR and layout analysis.
Watchdog
A Python library and shell utilities to monitor file system events in real-time.
pystray
A Python library for creating system tray icons and menus on Windows, macOS, and Linux.
fpdf2
A pure-Python library for generating PDF documents with minimal dependencies.
LemonSqueezy
A payment and licensing platform for digital products and SaaS, with APIs for subscriptions and license keys.
PyInstaller
A tool that bundles Python applications into standalone executables for distribution without a Python install.
Inno Setup
A free Windows installer creator used to build setup executables with a wizard-style UI and optional silent install.
Impact
The numbers that tell the story of our success and progress.
Screenshots That Don't Lie
Visual proof that this thing actually works
Ready to Experience the Magic?
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