Twelve case studies, anonymized down to the engineering: what broke, what constrained the fix, and what shipped. AI pipelines, distributed systems, infrastructure.
Zero-downtime blue-green deploys with health-gated rollback
Build-once / promote-only images, staging-tested with live migrations, then swapped atomically behind a reverse proxy. A container health gate decides each release: pass drains the old color, fail rolls back automatically with the old version still serving. Pre-migration database snapshots and expand/contract migrations make even schema changes reversible.
Docker Compose · Traefik · Postgres · shell orchestrationAgent-operated task engine
A distributed kanban where autonomous agents claim work via FOR UPDATE SKIP LOCKED under renewable leases, with a lazy TTL sweeper (no background worker), three-strike escalation to a human, and an append-only event log. Boards sync in real time over Postgres LISTEN/NOTIFY fanned out as server-sent events.
Drizzle · Postgres LISTEN/NOTIFY · SSE · contract-first APIIdempotent webhook ingestion at scale
A durable Postgres-backed queue accepting third-party webhooks with at-most-once delivery via upserts keyed on external IDs. Three self-healing layers guard against silent data loss: dual-trigger reconciliation, missing-ID backfill detection with tombstone anti-joins, and 30+ automated anomaly checks on latency and orphaned records.
Go · Postgres (SKIP LOCKED, matviews) · HMAC · advisory locksDatabase-backed job queue replacing no-code workflows
Replaced a stack of brittle no-code automations with a hand-rolled durable queue: lease columns, claim counts and heartbeats dispatching rate-limited jobs to external APIs, child idempotency keys for mid-flight recovery, and shadow / dry-run modes for testing safely in parallel with production.
Go · Postgres leases · gocron · bearer + HMAC authFrame-accurate video localization
An end-to-end dubbing pipeline: transcription with speaker diarization and word-level forced alignment, neural voice cloning, and per-segment audio time-stretching so synthesized speech matches the original timing without drift across multi-minute media — with vocal/instrumental separation to keep backing audio clean.
WhisperX · XTTS voice cloning · Demucs · FFmpeg · CTranslate2Round-trip translation of structured design documents
Extracting and re-injecting text across 3,000+ segments inside packaged document formats (nested ZIP/XML trees) while preserving exact element indices, inline formatting and layout — surviving a full export → translate → reimport round trip without corrupting structure.
Python XML/ZIP tooling · multi-format CAT interchangeEvolutionary prompt optimization
Discovering better translation prompts with a genetic algorithm — elitism, adaptive per-mutation weights, crossover and diversity maintenance — scored by a learned semantic-similarity metric under a multi-objective fitness function balancing quality, length and vocabulary.
BLEURT · LLM APIs · evolutionary operators · NumPyServerless GPU inference orchestration
Driving multi-minute image-generation workflows on serverless GPUs over WebSockets: enqueue, poll, stream large binary outputs, and recover job state across mid-inference network drops with bounded exponential backoff and clean worker teardown to prevent VRAM leaks.
RunPod · ComfyUI · WebSockets · S3 offloadMulti-provider AI gateway with cost accounting
Routing generation requests across many model providers behind one uniform adapter interface, with per-model concurrency limits, automatic failover, and session / daily / total cost aggregation — exposed over both async REST and streaming gRPC.
Go adapters · gRPC / protobuf · persisted in-memory queueMulti-tenant SaaS with row-level isolation
A type-safe full-stack platform enforcing tenant isolation on every query and a five-role permission hierarchy at the API boundary, with GDPR audit trails, multi-currency money handling and approval workflows.
tRPC · Prisma · Postgres · Next.jsReal-time mirror trading
Sub-3-second polling that detects new trades, sizes them proportionally to a different account's balance, rejects on excessive slippage, and settles against an on-chain order book — deduplicating by transaction hash while bounding memory and surviving connection-refresh cycles.
Python · Web3 RPC · on-chain CLOBNative macOS dictation pipeline
Local-first voice-to-text: low-level audio capture → on-device speech recognition → context injection from screen OCR, clipboard and selection → optional LLM cleanup → accessibility-API paste — orchestrating five macOS permissions and mid-recording device hot-swap with non-fatal failure handling.
Swift / SwiftUI · whisper.cpp · Accessibility & CoreGraphics APIs