Operator first. Builder now.
Fifteen years running B2B SaaS marketing taught me where revenue teams actually lose time. Now I build the systems that give it back.
The short version.
I'm Justin Parnell. I spent fifteen-plus years in B2B SaaS go-to-market: three runs as VP of Marketing, two as a founder, including a technical founder stretch building identity verification on the blockchain. I have owned pipeline numbers, brand, demand gen, product marketing, and the ops underneath all of it.
When AI agents became real, I noticed the gap wasn't models. It was that nobody inside revenue teams had the time or the background to wire models into actual workflows. So that became the job: an embedded, fractional GTM engineer who ships production systems inside your stack, starting in week one.
The practice runs as an agent factory. The biggest engagement to date spans 25 workstreams across marketing, sales, customer success, and the executive layer, and every one of them has a named owner on the client's team rather than a dependency on me.
Instructor at Pavilion, Athena Alliance, and Xapa. I publish what I learn on YouTube, LinkedIn, and Substack.
Three eras, one thread.
The operator years
VP of Marketing three times over, across B2B SaaS from growth stage to enterprise. Pipeline targets, team building, and the unglamorous ops work that decides whether marketing is trusted or tolerated.
The founder years
Two companies, including a technical founder run building identity verification on the blockchain. Learned to ship with no headcount, no budget, and no patience for slideware.
The builder years
Forward deployed inside revenue teams, shipping AI agents that do real work in production. The operator background is the edge: I build the system I would have demanded as the VP.
The work in public.
YouTube
Build walkthroughs and agent demos, recorded from the same desk in the photo above.
Substack
Longer-form breakdowns of plays, patterns, and what production AI inside GTM actually takes.
The running build log: what shipped this week, what broke, and what it changed.
The questions people ask me.
What is Justin GPT?
The practice name: Justin GPT LLC is the consulting company behind the work. One operator, embedded in your team, with an agent factory's worth of proven patterns behind him.
Do you work hands-on or through a team?
Hands-on. The person on this page is the person in your Slack, building. Where a build needs more hands, your team supplies them and learns by doing, which is the point.
Do you work remotely?
Remote-first from the SF Bay Area, with clients across the US. Workshops and kickoffs happen in person when it matters. Work runs in English and Spanish.
Where can I follow the work?
YouTube for build walkthroughs, Substack for longer breakdowns, and LinkedIn for the daily build log. All three are linked above, and the case studies show where the patterns came from.