How Josh Holt built an AI SDR that keeps LinkedIn reply rates above 20% — automatically
Josh Holt, Founder of NightlyX, turned LinkedIn outbound into a system that runs itself overnight — sourcing, writing, and optimizing without a human touching it, and keeping reply rates above 20%.
Useful links and tools
I wanted to make this as simple as possible. To create a new campaign, all you have to do is create new, name it, and then launch.
How it works
The challenge
Running LinkedIn outbound well isn't one job. Actually, it's four:
- sourcing and enriching the right leads
- writing (and constantly rewriting) sequences
- deciding which replies are worth a rep's time
- re-targeting campaigns as performance drifts.
Most tools handle a single piece of that chain, which means teams end up stitching several tools together and still checking in on all of them by hand, every day.
The insight that shaped NightlyX: the sending tool is already good at getting messages out. What's missing is the layer that decides what to send, who to send it to, and how to keep improving both without a human rewriting anything.
The solution: An AI SDR that runs the loop for you overnight
Josh built NightlyX to sit on top of a team's existing sending tool rather than replace it. Onboarding is short and doubles as the AI's whole knowledge base — a few questions about what the team sells, their offer, and their ICP feed straight into every message NightlyX drafts afterward.
How it works:
- Campaign setup: A short onboarding flow (what you sell, your offer, your ICP) creates a campaign profile that drives every message NightlyX writes going forward. Launching a new campaign is a two-step action — name it, then launch.
- Lead sourcing: Leads come in through an Apollo API key, a CSV import, or LinkedIn Sales Navigator, up to 50,000 per file, and get enriched automatically against that campaign profile.
- Sending (HeyReach): Once leads are loaded, the campaign runs on HeyReach itself — NightlyX doesn't send connection requests on its own.
- AI-drafted inbox with a trust ramp: Replies land in an inbox built outside HeyReach from scratch. Every reply starts as an AI-written draft that a human approves, typically for about the first seven days. An "AI IQ" score climbs from 0 toward 100 as the account earns trust; once it does, autonomous sending ("Autosend") can be switched on. Messages send individually — three separate messages rather than one long one, which the team credits with a meaningful reply-rate lift.
- Pipeline management: Replies get tagged automatically — hot, warm, cold, non-interested — and can be moved manually or by the AI as the conversation develops.
- Nightly optimization: Each night, NightlyX rewrites underperforming copy, readjusts targeting, and promotes whichever campaign variant is winning, pushing new leads into it automatically.
- Lead magnets: A newer feature lets a LinkedIn post act as a trigger (e.g., someone comments "guide") that fires an automatic reply and DM with a resource link — but only to people already connected, and paced deliberately so it doesn't read as spam or trip LinkedIn's limits.
- Analytics and alerts: An adaptive-targeting view shows reply rate and campaign health at a glance, flags campaigns that need attention (e.g., "redo targeting copy"), and can push events to Zapier or Slack via webhook.
The results
Looking at account performance at the time of the walkthrough:
- 29% reply rate over the past 7 days, 24% over the past 30 — consistently above the ~20% mark
- 18.9% reply rate across all campaigns on the account
- 16% connection rate, by design — the targeting stays narrow and specific rather than pulling from a broad LinkedIn Sales Navigator list
- Roughly 8 teams testing the product in early access
The product is still in active early access — email outreach was recently dropped entirely so the team could focus fully on LinkedIn.
Why it works
Two things stand out about this approach:
- Trust before autonomy. Rather than handing an AI SDR full control on day one, every account starts in human-approval mode and earns its way to autonomous sending through an "AI IQ" score — so outbound never goes fully hands-off before it's proven itself.
- Fewer, better contacts over broad reach. A 16% connection rate would look weak by volume-outbound standards, but it's the deliberate result of a narrow, specific target list rather than a wide Sales Navigator pull — and it's paired with reply rates that consistently clear 20%.
