PhilippTheServer

python

Python services, tooling and the packaging around them.

  1. Tracking Meals and Automating Shopping With an MCP Server

    An MCP server for meal tracking and grocery shopping automation: planned meals minus live stock, and why the v2 rebuild derives stock from an event journal.

    agents automation api-design architecture python

  2. Automating Web Shop Order Processing Before the Catalogue

    Web shop order processing automated first: Stripe webhook payment confirmation, stock reservations, outbox-driven DHL labels, two manual steps.

    automation architecture reliability python

  3. A Daily Digest of What Actually Got Merged, Built from MQTT and a Local LLM

    paho-mqtt subscriber to SQLite plus a local LLM: a daily digest that summarises merged pull requests per repository from diff stats, no cloud API.

    ci-cd observability python architecture

  4. The NTP Clock Jump That Made the Scheduler Skip a Week of Measurements

    time.time() vs time.monotonic() in a Python scheduler: a backwards NTP step delayed runs by nine days. Monotonic durations and a jump-injecting test.

    embedded reliability python linux

  5. One Local Endpoint for Every Agent Session

    OPENAI_BASE_URL=http://localhost:8080/v1 for every AI tool: one local FastAPI proxy that logs each request and refuses internal-only projects.

    llm security python

  6. Testing an Agent Harness Without Ever Calling the Model

    Unit testing a coding agent's tool-call permission layer with pytest and recorded fixtures: allow, deny or ask decisions with no model or API key.

    testing agents python

  7. A Deterministic Daemon That Turns a Labelled Issue Into a Pull Request

    git apply --check before git commit: an issue-to-PR daemon where the model only returns a patch and plain Python commits, pushes and opens the PR.

    agents python ci-cd

  8. The Transactional Outbox: Never Losing a Job You Already Committed

    Transactional outbox in Postgres: commit-then-enqueue loses jobs on a crash. A SKIP LOCKED relay to Redis Streams and an idempotent consumer.

    python architecture reliability databases

  9. Building the Dry-Run Path First, and Testing That It Sends Nothing

    if dry_run: return guards drift as side effects are added. Split the tool into a pure plan() and apply(), and test that dry run never calls the client.

    testing python automation infrastructure-as-code

  10. Idempotent Payment Webhooks with a Deduplication Table

    Payment webhook processed twice on retry: dedupe on the provider event ID with a primary key, committed in the same transaction as the side effect.

    python reliability api-design

  11. Modelling an Order Lifecycle as an Explicit State Machine

    Python order status as a state machine: a transition table and one transition_to method that raises InvalidTransition on moves like shipping a cancelled order.

    python architecture api-design

  12. Migrating Redis Consumers from Python to C++ on Constrained Hardware

    redis-plus-plus xreadgroup times out before its block timeout: set socket_timeout to 0. Replacing idle Python Redis stream consumers with C++.

    cpp python redis performance

  13. UUID Case Normalization as a Recurring Cross-Service Bug

    Uppercase vs lowercase UUID keys cause silent cache and database lookup misses between services. Normalise once at the boundary with str(uuid.UUID(value)).

    reliability architecture python testing

  14. Chaining Single-Purpose Redis Consumers into a Processing Pipeline

    XREADGROUP, XACK and XAUTOCLAIM: splitting one Python consumer into single-purpose Redis Streams stages with at-least-once delivery and crash recovery.

    redis architecture python

  15. A Python CLI That Scaffolds a Project Structure You Actually Want

    Python scaffolding CLI with only argparse and string.Template: generates src layout, pyproject.toml, Dockerfile and .gitignore, tested with tomllib.

    python architecture automation

  16. Replacing pip, venv, flake8, black and isort with uv and Ruff

    uv sync --locked and ruff check replacing pip install -r requirements.txt, venv, flake8, black and isort: uv.lock plus one pyproject.toml config.

    python ci-cd automation

  17. Configuration Precedence: Docker Secrets, Kubernetes Secrets, Environment, .env, Default

    Docker secrets in /run/secrets, Kubernetes secret mounts, env vars and .env: a Python resolver with fixed precedence that reports which source won.

    python infrastructure-as-code docker kubernetes

  18. An Exception Hierarchy and One Handler for FastAPI Error Responses

    FastAPI add_exception_handler on a base AppError instead of raising HTTPException in services: one status-code mapping and a consistent error body.

    fastapi python api-design

  19. Designing a Consistent FastAPI Response Envelope

    FastAPI response envelope with Pydantic Generic[T] and a custom APIRoute get_route_handler that wraps every response in success, data and error.

    fastapi api-design python

  20. A Feature-Module Layout for a FastAPI Application That Keeps Growing

    FastAPI APIRouter per feature directory with its own router.py, schemas.py and service.py, replacing a shared routers.py, schemas.py and crud.py.

    fastapi python architecture

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