We're hiring · Workflows

ComfyUI Engineer.

Own the workflows that power millions of AI images every month. You think in nodes, you debug in graphs, you care obsessively about output quality.

Remote · global
Full-time / contract
Senior IC + equity
workflow_headshot_v3.jsonrunning
The role

Runflow is the AI image and video infrastructure layer for production. We power the AI headshots, fashion shoots, and product photography that companies like BetterPic and BetterStudio ship every day, millions of images a month, with quality scored before delivery.

We're hiring a ComfyUI Engineer to own the workflows that produce them. This isn't a research role. You'll ship production workflows that directly impact output quality, customer retention, and revenue. You're the person who decides which checkpoints, which LoRAs, which control nets, which sampler, and how it all stays under VRAM and latency budgets at scale.

If you debug node graphs in your sleep, train LoRAs for fun, and have strong opinions on face similarity vs. likeness preservation, this is for you.

Quick facts

TeamWorkflows
Reports toHead of AI
LocationRemote · global
TypeFull-time or contract
CompensationSenior IC + equity
StartASAP
Representative projects

What you'd ship in your first 6 months.

Concrete, shippable, on the live roadmap. Not hypothetical. We expect every one of these to land.

Project 01

Ship a face-similarity workflow that holds 99%+ likeness across 500-image batches

Pick the checkpoints, design the conditioning chain, calibrate the IP-Adapter / face-swap stack, and run the eval. Hand it off to Sentinel for live scoring.

Project 02

Cut p95 latency on the BetterStudio pipeline by 40%

Profile VRAM, swap samplers, prune the graph, parallelise where it pays. The win has to hold across realistic batch shapes, not synthetic benchmarks.

Project 03

Train a domain-specific LoRA from scratch for a new product vertical

Curate the dataset, set up the training loop, ship the LoRA into the workflow, validate against held-out evals. Document the recipe so the next vertical takes a week instead of a month.

Responsibilities

What you'll be doing.

You'll own the full lifecycle, from prototype to production at scale.

Build, optimise, and debug ComfyUI workflows for human-centric and product image generation

Profile node chains. Cut VRAM, latency, and cost without sacrificing quality

Wire workflows into Runflow's Solutions API, Python, TypeScript, REST

Run batch inference and post-processing at production scale (millions/mo)

Iterate on output quality. Hand off failure modes to Sentinel; learn from its scores

Build dynamic conditioning systems, variable poses, styles, backgrounds, products

Maintain a versioned, documented workflow repo other engineers can read

Train and fine-tune checkpoints + LoRAs (Flux, SDXL, Wan-style pipelines)

Requirements

About you.

You may be a good fit if…

  • You've shipped ComfyUI in production for 6+ months, setup, custom nodes, debugging gnarly graphs
  • You have deep working knowledge of diffusion models (SDXL, Flux, the open-source release of the month)
  • You've built workflows tuned for realism and identity preservation, face similarity is second nature
  • You're comfortable with ControlNets, IP-Adapters, segmentation, and the full conditioning toolbox
  • You optimise compute. You know when to swap a sampler vs. retrain a LoRA
  • You're fluent in GitHub, Python, and REST, the workflow is just one part of a system

Strong candidates also have…

  • Have trained LoRAs or fine-tuned checkpoints (Flux/SDXL/Wan) end to end
  • Use the diffusers library and Hugging Face tooling fluently
  • Have built integrations connecting ComfyUI to external services (Plytix, Shopify, custom CMSes)
  • Have shipped production pipelines at scale (>100K images/day) and lived to tell the war stories
  • Have a public portfolio of workflows you'd be proud to walk us through

What we're not looking for

A specific number of years. A specific degree. A specific stack. We hire on whether you can ship end-to-end and whether you have taste. Everything else is noise.

Tech stack

What we work with.

Backend

Node.jsPythonPostgreSQLRedis

Workflow

ComfyUIdiffusersPyTorchHugging Face

Infra

AWSCloudflare R2ModalNeon

Tools

GitHubLinearSlackSentinel
How we hire

Five steps. Decision speed is part of the offer.

We move fast because senior candidates with multiple offers reward the team that respects their time. Whole loop fits in two weeks.

01/5

Application submitted

Form, ~5 min

We read every word of every application. No silent rejections, ever.

Triaged within 5 business days
Apply now
02/5

Take-home challenge

2 hours max, your time

A small, real Runflow problem. We score the prompts and decisions you made as much as the output itself.

Reviewed within 3 business days
03/5

30 minutes with the CTO

30 min, live

Quick conversation about your take-home, the team, and how you work day-to-day.

Decision in 48 hours
04/5

Paid challenge, 2 days

2 days, we pay for your time

A bigger problem we pay you to work through. We care about outcomes, not process. AI tools more than welcome.

Decision in 48 hours
05/5

Closing interview

90 min, live

Casual chat with the two founders.

Decision in 24 hours

Show, don't tell.

We value proof over promises. When you apply, include examples. Things that stand out:

Face-similarity workflows with consistent identity preservation across batches
Batch generation pipelines with quality gating built in
Custom conditioning logic or node modifications you wrote yourself
LoRA training results and the methodology you used
Apply

Ready to ship?

Five minutes. We read every word. Yes / no / not-now within 5 business days, always.

You're applying for ComfyUI Engineer · Workflows

We commit to a yes / no / not-now within 5 business days. Always. No silent rejections.

Apply now