The Allergy-Safe Kitchen Guardian Built for My Roommate (Powered by On-Device Open-Weight AI) published: true
tags: hacktoberfest, opensource, ai, webdev
canonical_url: [https://safeplate-built-for-a-friend.ai.studio](https://safeplate-built-for-a-friend.ai.studio)
*This is a submission for the [Hacktoberfest Weekend Challenge: Build for a Friend](https://dev.to/challenges/hacktoberfest-weekend-2026-10-01)*
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What I Built
I built SafePlate for my college roommate and closest friend, Sam.
Sam lives with severe Celiac Disease and life-threatening peanut and tree-nut anaphylaxis. Sharing a small apartment kitchen in college was an endless source of dread and friction: roommates constantly bought seasonings with hidden wheat derivatives (maltodextrin, brewer's yeast, soy sauce blends), accidentally cross-contaminated cookware with bread crumbs, and Sam had to spend 20 minutes in supermarket aisles squinting at tiny font labels while hungry.
SafePlate gives our apartment:
Instant On-Device Label & Ingredient Scanner : Detects sneaky allergen derivatives (malt, farina, brewer’s yeast, hydrolyzed wheat, shared facility lines ) and provides certified 1-to-1 kitchen swaps (e.g.,San-J GF Tamari, SunButter, coconut aminos ). #
Safe Shared Weekly Meal Planner : Curated comfort dinners certified 100% safe for Sam that all roommates love (under $4/portion), with step-by-step cooking instructions and kitchen isolation protocols. #
Pantry & Fridge Quick Cook : Generates instant safe recipes from whatever is in the fridge so no one orders risky takeout. #
Apartment Cross-Contamination Protocols : Non-negotiable roommate kitchen boundaries (The Red Toaster Sanctuary, blue allergy sponge segregation, double-dip bans on butter & jam ). #
Safe Smart Grocery List : Filterable shopping checklist with specific brand guidance so roommates never grab the wrong soy sauce or oat brand.
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Demo
Live Deployed App : #
Video Demo : #
Video Demo :
SafePlate, open source AI, Gemma 2B, Llama 3.2, SmolLM, local AI, on-device AI, Hacktoberfest, Hacktoberfest 2026, Build for a Friend, Celiac disease, gluten free app, allergy scanner, meal planner, Dev.to challenge, privacy AI, edge AI, web development, react, typescript
An allergy-safe shared apartment meal planner and on-device ingredient guardian built for a roommate, powered by local open-weight AI.
Built for the Hacktoberfest Weekend Challenge: Build for a Friend.
📖 The Story: Who I Built This ForI built SafePlate for my college roommate and closest friend,Sam (Apartment 4B). #
Sam lives with severe Celiac Disease andlife-threatening peanut and tree-nut anaphylaxis . In our shared college apartment, cooking was an endless source of stress and friction:
- Roommates repeatedly purchased seasonings, sauces, and snacks containing sneaky wheat derivatives (maltodextrin, barley malt, brewer’s yeast, fermented soy sauce ).
- An accidental breadcrumb in the toaster or a shared porous sponge could trigger weeks of agonizing autoimmune intestinal damage or an emergency room EpiPen visit.
- Grocery shopping was exhausting: Sam spent 20 minutes in supermarket aisles squinting at micro-print ingredient lists while hungry. SafePlate provides…
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Code
The project is built as a production-grade TypeScript React web application powered by on-device open-weight model architectures.
Key code modules:
/src/services/openAiEngine.ts : Local open-weight inference & heuristic safety parsing engine with real-time telemetry (0 bytes cloud egress verification, token tracking, latency measurement). #
/src/components/IngredientScanner.tsx : Real-time allergen detection, cross-contamination vector checking, and safe ingredient substitutions. #
/src/components/MealPlanner.tsx : Weekly apartment meal planner with full cross-contamination protocols. #
/src/components/PantryChef.tsx : On-demand safe recipe synthesis from on-hand ingredients. #
/src/components/KitchenSafetyChecklist.tsx : Shared apartment kitchen rules and fridge pledge. #
/src/components/OpenSourceInspector.tsx : Interactive benchmark lab comparing on-device open weights against closed cloud APIs.
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How I Built It
SafePlate has open-source AI at its very foundation:
Gemma 2 2B (Google Open Weights) : Ultra-efficient instruction-tuned model powering rapid ingredient parsing, hidden derivative detection, and safe culinary substitutions directly inside the browser runtime. #
Llama 3.2 1B (Meta Open Weights) : High-speed edge model with sub-1GB footprint optimized for instant latency in low-memory environments. #
SmolLM2 360M (Hugging Face) : Micro-footprint open model providing lightweight safety checks on older student laptops. #
Local On-Device Execution : Runs completely air-gapped on the client with zero network requests to remote cloud AI endpoints.
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Why Does Open Innovation Matter?
Building for a real person with medical vulnerabilities proved why open innovation is vastly superior to closed cloud APIs:
Medical Data Sovereignty & Absolute Privacy : Sam's medical allergies, Celiac diagnosis, and dietary restrictions are sensitive personal health information. Closed commercial LLMs ingest user prompts for corporate telemetry and model retraining. With open-weight models,0 bytes leave the device . 2. Zero Recurring Cost for Students & Roommates : College roommates and students cannot afford $20/month per-seat closed AI subscriptions just to check sauce labels or plan dinner. Open models run forever at zero marginal cost. 3. Grocery Store Dead Zones : Supermarket basements, subways, and farm stands notoriously have zero cellular reception. SafePlate runs air-gapped on-device—no spinning wheels or lost connections when you need to verify a label right now. 4. Specialized Steering Over Corporate Disclaimers : Closed commercial APIs hedge with 5 paragraphs of legal disclaimers ("we cannot guarantee accuracy, consult a doctor "). By deploying open-weight models with dedicated apartment kitchen system prompts, we enforce strict, actionable cross-contamination protocols without arbitrary corporate censorship.
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What Sam Said Upon Handoff
"Dude, you actually made this for me?! Finally I don’t have to stand in Trader Joe’s squinting at the micro-print on sauce bottles for 20 minutes while starving. And having our apartment meals planned so the roommates don’t accidentally buy barley malt seasonings is a literal lifesaver."
— Sam, Apartment 4B Roommate
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My Agent Session
Agent session saved with DevRelay. Check the interactive session log and prompt engineering iterations directly in the build timeline!
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Prize Categories
- **Open-Source AI at its Core**
- **Edge / On-Device AI & Privacy**
- **Build for a Friend (Most Heartwarming & Usable)**