Jared Lemler SHEET 01

Backend engineer · Builder

From wiring buildings to wiring systems.

I'm Jared Lemler, a backend engineer and former electrician. I build and run production systems end to end: data pipelines, developer tooling, and federated platforms, with Python/FastAPI and TypeScript/Fastify on Postgres.

Calm under pressure, obsessed with craftsmanship, and always looking for clearer, more honest systems.

Studying nowField notes
  • LiveKit SFU for remote recording: next step for the VoxPort recording booth, multi-guest sessions over an SFU instead of local-only capture. Part of VoxPort.

  • Dagster + dbt patterns: asset checks, season partitioning, and write-audit-publish, applied on nfl-dagster.

  • Snowflake: warehouse layering (RAW, STAGING, MARTS) and credit-aware cost control.

Photo of Jared Lemler
FIG. 01The engineer · Pacifica, CA
Status
  • Building VoxPort Federated podcast platform on the AT Protocol. Live at voxport.live.

  • Contributing to seamux Open-source, multi-agent session dashboard for Claude Code and Codex in cmux. Working on OpenCode support: issue #4 and PR #8 (in review).

  • Open to backend & data engineer roles Remote or SF Bay Area.

DWG 01

General notes

From electrician to backend engineer.

I started my career in construction and electrical work. I was coordinating with teams, reading plans, and wiring systems that had to be safe, reliable, and maintainable. I completed my apprenticeship, earned my journeyman card, and led crews on commercial jobsites. That work taught me craftsmanship, patience, and how to stay calm under pressure.

Over time I got hooked on the logic behind automation and control systems. Eventually that pulled me into software. Now I use the same mindset to design APIs, databases, and services that solve problems for people instead of just chasing hype.

Note 01 · How I learn new domains

I pick up new domains fast. Podcasting pulled me in, and I taught myself how a platform actually works (RSS distribution, hosting economics, the AT Protocol as an identity and record layer) well enough to architect one. That's the pattern: get curious, learn the domain honestly, then build.

I care about honesty, ownership, and better systems. That shows up in the tools I use (Python, FastAPI, Postgres, ATProto), the projects I build, and the way I learn: in public, without pretending to have it all figured out.

Brand pillars

  • Craftsmanship: do it right, not just fast.
  • Purpose: build things that make life better.
  • Calm clarity: break problems into clear steps.
  • Independence: prefer open, user-owned systems.

Outside of code

I live in Pacifica, CA (SF Bay Area) with my wife and our dogs. Outside of work you'll usually find me gaming, hiking and exploring areas I haven't been, and going down rabbit holes of topics that are interesting and new to me.

DWG 02

Panel schedule

What I'm good at. Backend-first, with the toolchain and discipline to ship and operate it.

LP-1Backend & data
  • 01Python, FastAPI, Django
  • 02TypeScript, Fastify, Node.js
  • 03PostgreSQL, SQLAlchemy 2.0, Prisma
  • 04REST API design, auth (JWT), data modeling
  • 05Background jobs, ETL, real-time event processing
  • 06WebSocket consumers & backpressure
  • 07Pydantic validation, Alembic migrations
  • 08Pandas, CSV/JSON pipelines, batch processing
LP-2Systems & delivery
  • 01Docker & docker-compose
  • 02CI/CD: CodeQL, Gitleaks, Bandit
  • 03Observability: Sentry, OpenTelemetry, Axiom
  • 04Cloudflare R2, Fly.io, Neon, AWS (EC2, S3)
  • 05Testing with pytest / Vitest
  • 06AT Protocol & decentralized apps
  • 07Multi-env deploys (dev/staging/prod branching)
  • 08Structured logging & access-log monitoring
LP-3How I work
  • 01Breaks work into clear steps
  • 02Calm, honest communication
  • 03Strong bias toward learning
  • 04Docs as a progress compass: has agents maintain clean, detailed markdown (status, worklogs, plans) so project state is always legible to humans and the next agent.
  • 05AI-native workflow: treats agents as collaborators with structured handoffs, not magic buttons.
  • 06Learning out loud: writes to understand, not just to publish.
DWG 03

As-builts

Projects that represent how I think. Real problems, real constraints, and systems I care about.

A-01

VoxPort: creator tools on the AT Protocol

Fastify · Next.js · ATProto

Decentralized creator tools where podcasters own their identity, feed, and audience. Built on the AT Protocol with custom lexicons and a Fastify/Next.js stack to keep creator data portable and under their control. Also published an AT Protocol skill on skills.sh to help others build on the protocol.

  • Federated ingestion at scale: resilient WebSocket consumer with bounded memory backpressure (1,000-event cap) and 100-event batching. Together with in-memory caching and longer cursor flush intervals, this cut production DB operations 96%, from ~209K to ~3K to 8K per day.
  • Audio extraction worker: dedicated ffmpeg worker with SSRF guards, FOR UPDATE SKIP LOCKED job claiming, and Cloudflare R2 content-addressed storage.
  • Multi-env production deploy: API on Fly.io, web on Vercel, Postgres on Prisma Postgres, with Sentry + Axiom + OpenTelemetry observability.

NOTE:I care about ownership and systems that don't trap people. This project pushes me to think beyond a single app and into protocols and ecosystems.

Try VoxPort →
Fastify Next.js ATProto
A-02

nfl-dagster: NFL contract value pipeline & ask tool

Python · Dagster · Snowflake · dbt

A production ELT pipeline and grounded LLM ask tool. Dagster orchestrates NFL play-by-play, schedules, and contract data (2015 to present) into Snowflake RAW, STAGING, and MARTS layers via dbt, then publishes finished marts to Postgres for a public website with a Claude-powered question tool that only states numbers it got from a query.

  • Production ELT: 20 Dagster assets with season partitions, refreshed on schedule by Dagster+ Serverless. Each load deletes, copies, and audits inside one Snowflake transaction and rolls back on failure; 43/43 dbt tests passing in prod.
  • Audited serving layer: finished marts publish to Postgres in a single-transaction swap, verified against Snowflake by row counts and primary-key fingerprints, so the website never queries the warehouse.
  • Grounded LLM Q&A: a Claude Haiku tool loop over select-only, parameterized, read-only queries with timeouts and row caps. The code rejects any number not returned by a query; an 81-question eval suite scores 78/81 (30/30 refusals) at ~$0.0005 and 4s per question.

NOTE:Ran like production: rate limits, spend caps, no stored user data, required CI checks, least-privilege roles, and a monthly resource monitor.

Try the ask tool → Source on GitHub
Python Dagster Snowflake dbt FastAPI
A-03

Travel Wishlist: full-stack travel planner

FastAPI · React · Maps · Analytics

A real deployed app for saving, organizing, and analyzing travel. Combines a FastAPI/Postgres backend with a React frontend, including map views and basic analytics around visits and plans.

  • Full-stack architecture: FastAPI, PostgreSQL, and Docker with JWT auth, Pydantic validation, and a reusable CRUD service layer.
  • External API integration: city-based weather lookup with ~100ms response times, plus an interactive map layer for geographic visualization.
  • Calendar itinerary system: monthly/agenda views for trip planning with date-based organization of saved cities.

NOTE:It's a complete loop: database design, APIs, frontend integration, deployment, and iteration based on actual usage.

FastAPI PostgreSQL React Deployable
A-04

doc-lok: pre-prompt context condenser

TypeScript · Node.js · Zero-dep

A pre-prompt middleware that condenses link-bearing Markdown by resolving remote links into compact cryptographic markers, cutting context token consumption and API latency for LLM workflows. Published on npm with zero runtime dependencies.

  • Context window optimization: condenses prompt payloads by replacing unchanged remote Markdown links with compact markers, drastically cutting token usage.
  • Conditional caching pipeline: two-phase network verification using HTTP HEAD probes and If-None-Match ETag validation to skip unchanged resources.
  • Zero-dependency architecture: CLI and library built exclusively on native Node.js APIs. No third-party supply-chain risk, minimal cold-start overhead.

NOTE:A focused, shippable tool that solves a real LLM-context problem with a craftsman's restraint: do one thing well, with no dependencies you don't need.

npm package → Source on GitHub
TypeScript Node.js SHA-256 ETag
DWG 05

Junction box

I'm open to backend roles, collaborations, and projects that make life better for people or animals, or push decentralized, user-owned tech forward.