When we started on Replit in mid-2025, the idea you could build a commercial-grade B2B app on it was … a fiction. With very short context windows and limited capabilities, thinking you could vibe code a “Salesforce” was borderline ridiculous. Maybe it still is,
But … by late 2025, Replit got really, really good:
- Context windows can be unlimited
- Sub agents solving tough issues
- Design mode + Fast mode
It finally got great.
Now… imagine by late 2026 if it could run 24×7.
It just keeps building, all the time. Not just when you are online. Not even just for hours at a stretch.
But constantly, 24×7.
New features, for you to look at, already built and tested. Multiple versions of everything. 24×7 QA of everything. Autonomously building new ideas without you even asking, for you to review when you log back in. Ideas you didn’t even think of.
That would really change software development.
The Bottleneck Isn’t the Agent. It’s You.
Right now, the agent can only work when you’re watching. You kick off a feature, wait 20 minutes, review, give feedback, wait again. Go to sleep, the agent sleeps too.
What if it never stopped?
You describe what you want Monday morning. Go about your day. Check in after lunch to find 8 features built and waiting for review. You approve 6, give feedback on 2. Take your afternoon calls.
By dinner the 2 are fixed. 4 more are built. Plus the agent pings you: “I noticed users are dropping off on the onboarding flow. I built 3 alternative versions and tested them. Here’s the data. Want me to ship the winner?”
You didn’t ask for that. The agent just… did it.
This isn’t theoretical. Our GTM AI agents at SaaStr already work this way at a rudimentary level. They run campaigns, learn from results, adjust, keep going. Come back to you when they need direction. Otherwise they just execute.
Now apply that to building software.
24×7 Math Changes The Calculation
Let’s do the real math on 24×7 development.
A good engineer ships maybe 1-2 meaningful features per week. Call it 75 features per year. A 5-person team? Maybe 300 features per year, accounting for coordination overhead, meetings, code reviews, vacations.
Now let’s talk about a 24×7 agent.
If an agent can ship just 2 features per day—and current agents can already do this for well-scoped features—that’s 730 features per year. From one agent.
But it gets crazier.
The agent doesn’t just build. It builds multiple versions. It tests. It iterates. It fixes its own bugs. Let’s say only 50% of what it builds is good enough to ship. That’s still 365 features per year.
365 features. One agent. Zero salary. Zero benefits. Zero burnout.
Compare that to your 5-person team doing 300 features with $1M+ in fully-loaded costs.
But wait. We’re not done.
What happens when you run 3 agents in parallel? 10 agents? Each one working on different parts of the product, 24×7, all year?
10 agents × 365 features = 3,650 features per year.
That’s more than most enterprise software companies ship in a decade.
The Timeline Compresses to Almost Nothing, Really
Day 1: You describe your CRM. Agent builds core data model, UI, auth, and 5 basic features.
Day 7: You have 35+ features. Pipeline management, deal stages, activity logging, email integration, basic reporting, mobile views, API, webhooks. All tested. All working.
Day 30: 150+ features. You’ve surpassed most vertical CRMs on the market. The agent has tried multiple approaches for each feature, kept the best ones, documented everything.
Day 90: 400+ features. You’re not competing with Pipedrive anymore. You’re competing with HubSpot.
Day 365: 1,000+ features. Plus a year of 24×7 QA. Plus continuous refactoring. Plus automatic security patches. Plus proactive improvements you never asked for.
All from 20 minutes of direction per day. Maybe 120 hours of your time total for the year.
A traditional startup would need 4-5 years and $10M+ in engineering costs to build what you built in 12 months for the cost of compute.
The Compounding Is What People Miss
Today’s agent builds v1. Tonight it builds on v1 to get v1.1. By morning, v1.2. Each cycle adds features. Each iteration improves the codebase.
And because the agent never stops, it’s not just building features. It’s thinking ahead.
“Based on usage patterns, users are trying to do X but we don’t support it. I built it. Here are 3 approaches. This one tested best.”
“I found a security vulnerability in a dependency. Already patched. Here’s the changelog.”
“Competitor Y just launched feature Z. I built our version overnight. Want to review?”
The agent becomes proactive, not reactive. It’s not waiting for your instructions. It’s bringing you ideas.
Over 365 days, this compounds into something almost unrecognizable from where you started. Not just more features—a fundamentally more mature, more robust, more complete product than any traditional team could build in the same timeframe.
Self-Healing Apps Over 365 Days
Now multiply the self-healing concept across a year.
The agent runs functional tests 24×7. It catches regressions at 2am. Diagnoses root cause. Writes the fix. Runs the test suite. Deploys. All while you sleep.
Over 365 days, how many bugs does it catch and fix autonomously? Hundreds? Thousands?
How many production incidents that would have woken you up at 3am? Zero.
How many customer complaints that would have hit your support queue? Fraction of what you’d normally see.
Your app doesn’t just heal itself. Over a year of 24×7 QA, it becomes hardened in ways that normally take 5+ years of production battle-testing. Every edge case found and handled. Every race condition eliminated. Every failure mode accounted for.
By month 12, you have enterprise-grade reliability. Not because you hired an SRE team. Because the agent never stopped testing.
Technical Debt Becomes a Non-Issue
Nobody fixes small stuff because pulling an engineer off feature work doesn’t make ROI sense. “We’ll get to it later.” Later never comes. The codebase rots.
A 24/7 agent changes that math entirely.
Between feature builds, it monitors for deprecated dependencies. Finds security vulns. Spots code smells. Refactors the ugly stuff. Updates packages before they become breaking changes.
Not because you asked. Because it has cycles to spare and it knows a healthy codebase ships faster.
You stop having “cleanup sprints.” The cleanup just happens.
The Three Phases
2025: Agents got great. Unlimited context windows. Sub agents. Design mode + Fast mode. You can finally build a real, production-ready v1. Not a demo. A product.
2026: Agents run 24×7. The economics start working. Agents build continuously—not just when you’re online. You give 20 minutes of direction per day, wake up to new features built and tested. 365 features per year per agent. A solo founder can out-ship a 5-person team.
2027: Agents at enterprise scale. This is where it gets crazy.
Salesforce has ~12,000 engineers. Maybe 8,000 writing code. At 40 hours/week, that’s ~16 million engineering hours per year.
A 24/7 agent runs 8,736 hours per year.
To match Salesforce’s raw engineering output, you’d need roughly 1,800 agents running 24×7.
At 2025 costs? Completely prohibitive.
At 2026 costs? Still expensive—maybe $50-100K/month for that scale.
At 2027 costs? Could be $10-20K/month. Less than one senior engineer.
Obviously agents aren’t as good as senior engineers. They lack judgment, creativity, architectural vision. But for raw feature velocity? For grinding through the long tail of functionality? For keeping up with the backlog that never ends?
The gap closes faster than anyone expects.
I’m Not the Only One Seeing This
And I’m not relying on CEOs talking their book or researchers worried about AGI doom.
The builders are sharing real data.
Cursor just hit $1 billion in annualized revenue with 1 million daily users. They went from $1M to $100M ARR in 12 months—one of the fastest SaaS ramps in history. Users report 30% productivity gains. A University of Chicago study found teams using Cursor merged 39% more pull requests than non-users.
Replit went from $10M ARR to $100M ARR in 9 months after launching Agent. They’ve powered over 2 million apps built by users. Rokt built 135 internal applications in 24 hours using Replit Agent. Zinus saved $140,000 and cut development time in half building analytics dashboards.
YC is seeing it in their portfolio.
Jared Friedman (YC Group Partner) said at Demo Day that one-quarter of YC founders now have over 95% of their codebase AI-generated. These are highly skilled founders who, just a year ago, would have built everything themselves. Now AI does the heavy lifting.
Amjad Masad says Y Combinator founders are telling him: “We thought we’d need a CTO. We turned to Replit first. We’re on month three and haven’t had to hire anyone. We think of Replit as our CTO.”
The independent benchmarks back this up.
METR (an AI safety research org, not a company selling anything) measures how long AI agents can work autonomously. The data is striking:
Claude Opus 4.5 just hit a 50% time horizon of approximately 4 hours and 49 minutes—the highest ever recorded. That means it can complete tasks that take skilled humans nearly 5 hours, with 50% reliability.
For context: Claude 3.7 Sonnet was at 59 minutes in February 2025. GPT-5.1-Codex-Max hit 2 hours 53 minutes. Opus 4.5 nearly doubled that.
And the trend is accelerating. From 2019-2024: task duration doubled every 7 months. From 2024-2025: it’s doubling every 4 months.
Extrapolate that curve and you hit 16+ hour tasks by early 2027. Month-long projects by end of decade.
This is why every founder needs to pay attention.
The startup that figures out 24/7 agent development in 2026 will ship more in 12 months than their competitors ship in 5 years. By 2027, they’ll be operating at a scale that traditional teams literally cannot match at any cost.
Not because the agents are smarter than their engineers. Because the agents never stop.
Maybe You Really Could Vibe Code Your Own Salesforce. Or At Least, Something Close To Part Of It.
Here’s what keeps me up at night.
Salesforce has been building for 25 years. Thousands of engineers. Billions of dollars. Let’s say they’ve shipped 5,000 meaningful features over that time. (Honestly, probably less—lots of those engineering hours went to infrastructure, scale, acquisitions, rewrites.)
With 10 agents running 24×7 for one year, you could theoretically ship 3,650 features.
You could build 70% of Salesforce’s feature surface area in 12 months.
Obviously there’s nuance. Salesforce has enterprise scale, security certifications, 25 years of battle-tested production. You can’t replicate that overnight.
But for a vertical SaaS? A focused use case? A specific industry?
You absolutely could build something that competes on features. In one year. With almost no team.
What This Means for Founders
If you’re building a software company today, you need to think about this.
The competitive moat of “we have a big engineering team” is about to erode. Dramatically. The startups that figure out 24×7 agent development first will ship at speeds that traditional teams can’t match.
The winners won’t be the best engineers. They’ll be the best at directing agents. At reviewing output. At providing clear feedback. At knowing what to build.
Product sense becomes the differentiator, not engineering capacity.
What This Means for Engineers
This isn’t “AI will take your job.” It’s “AI will change your job.”
The engineers who thrive will be the ones who learn to work with 24/7 agents. Who can review and improve agent-generated code. Who can architect systems that agents can build and maintain.
The ones who resist will struggle. Not because they’re bad engineers—because they’re optimizing for a world that’s disappearing.
The Questions Nobody’s Answering Yet
If this timeline plays out, we need to rethink some fundamental assumptions about software.
1. How much do you charge for software that can be built 100x faster?
The old model: software is expensive because engineering time is expensive. A custom enterprise app costs $500K because it takes a team of 5 engineers six months to build.
The new model: that same app gets built in a week by agents running 24/7. Your cost basis drops by 90%+. Do you pass that on to customers? Do you keep the margin? Does software pricing collapse entirely?
SaaS has been a 70-80% gross margin business for two decades. What happens when your competitors can spin up equivalent functionality for 1/100th the cost?
2. Does feature cloning get compressed to hours?
Today, if a competitor launches a killer feature, you’ve got 6-12 months before they pull away. Your team can prioritize, build, and ship a response.
With 24/7 agents? Your competitor launches Monday morning. By Tuesday, your agents have analyzed it, specced a clone, and started building. By Friday, you’re in beta.
Feature advantages become measured in days, not quarters. The moat from “we built it first” shrinks dramatically.
3. Does feature differentiation even matter anymore?
Outside of genuinely complex or unique software—think Figma’s multiplayer engine, or Stripe’s payment infrastructure, or Salesforce’s ecosystem—does having “more features” mean anything?
If any competent team can spin up 1,000 features in a year with 24/7 agents, features become commoditized. The differentiation shifts to:
- Distribution. Who can get in front of customers?
- Data. Who has proprietary data that makes the product smarter?
- Brand. Who do customers trust?
- Integrations. Who’s embedded in the workflow?
- Support. Who helps customers succeed?
The actual building becomes table stakes. Everyone can build. The question becomes: what else do you have?
This is a massive shift. For 20 years, “we have better engineers” was a legitimate competitive advantage. That advantage is about to get arbitraged away.
24×7 Agents Will Change Things Radically. Once Again.
2025 proved agents can build a great v1.
2026 is about what happens when the agent never stops. When it keeps building, keeps testing, keeps improving—and comes back to you only when it needs direction.
It never stops building.
Maybe you really could vibe code your own Salesforce. Or at least, somewhat close.
