Vibe Coding vs. Buying SaaS: When to Build and When to Buy
The "cancel your SaaS and build your own" posts always leave out the real costs: build time, maintenance, and the revenue you didn't generate while coding. Here's the break-even math.
Jake Mercer
Growth Strategist · Ea-Nasir.co
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Quick answer
Build your own tools when the SaaS is over $100/mo and the use case is internal with low reliability requirements. Keep paying for SaaS when it's customer-facing (landing pages, checkout, email), under $100/mo, or when the tool has ongoing development you can't replicate. For most automations, check Make first at $9/mo before writing a single line of code.
The Reddit post format is familiar: "Cancelled $800/month in SaaS by building my own tools in a weekend. Here's the full breakdown." It gets 3,000 upvotes and spawns a thread of people planning to do the same. Some of those builds make sense. Most don't. The "cancel your SaaS" narrative ignores the real costs: time to build, time to maintain, reliability gaps, and the opportunity cost of not doing actual business work during the build.
Where the Narrative Is Right
There are genuinely good candidates for vibe coding over SaaS. Simple internal tools with no external reliability requirements. Custom dashboards that aggregate data from your own systems. One-off automations you'd otherwise pay Zapier $50/month to run forever. Integration scripts between tools that have no native connection.
The common thread: these are low-stakes, internal-use tools where a day of downtime or a bug in the logic doesn't cost you customers or revenue. If the tool breaks, you fix it. No SLA, no support ticket, no reputation damage.
The Four-Question Framework
1. Is this a customer-facing tool or an internal tool?
Customer-facing tools (landing pages, checkout flows, email systems, sign-up forms) have reliability requirements that homegrown solutions rarely meet consistently. When your Leadpages landing page has 99.9% uptime and your vibe-coded Flask app is down every time your VPS restarts, you're losing leads. Keep paying for customer-facing reliability.
Internal tools (reporting dashboards, data transformations, internal notification systems) have lower reliability requirements. A 4-hour outage of an internal analytics script costs you nothing in revenue. Build these.
2. Does the SaaS have ongoing development your build won't have?
The SaaS tools you pay $30 to $200/month for are investing that revenue into feature development, security patches, and infrastructure. Your vibe-coded alternative is frozen at the version you shipped. GetResponse ships new email templates, deliverability improvements, and integration updates continuously. A homegrown email tool stays at whatever state you left it in. Try GetResponse free.
3. What is the fully-loaded cost of building and maintaining it?
Replace Leadpages ($37/month) with a custom landing page solution: initial build time 20 to 40 hours at $50 to $75/hour equivalent value = $1,000 to $3,000. Maintenance: 2 to 4 hours/month. Annual maintenance cost: 36 hours at $75 = $2,700. Year-one total: $1,000 to $3,000 build + $2,700 maintenance = $3,700 to $5,700. Leadpages year-one cost: $444. The build decision costs $3,256 to $5,256 more in the first year to avoid $444 in SaaS fees. Year two breaks even only if maintenance drops significantly, which it usually doesn't.
This math shifts when the SaaS is expensive. Replace a $300/month tool with a 40-hour build ($3,000) and $500/year maintenance ($1,500 + $3,000 = $4,500 year one). SaaS cost year one: $3,600. Break-even happens partway through year two. From year three onward, you're saving $2,100/year. That build decision has a reasonable ROI.
4. Can Make or n8n do this for $10 to $30/month instead?
Before vibe-coding an integration or automation, check Make. Most integration use cases that prompt people to write custom scripts are already handled by Make scenarios at $9 to $16/month. n8n self-hosted on a $6/month VPS handles complex multi-step logic without code. If the automation you're about to build can be built in Make in 2 hours instead of 20, the economics are obvious. Try Make free.
What to Keep Paying For
Email marketing platforms: the deliverability infrastructure alone justifies the cost. Getting emails into inboxes requires domain authentication, IP reputation management, and ongoing compliance with ESP policies. This infrastructure takes years to build and is not something you should replace with a script. Tools like beehiiv and GetResponse handle this for $15 to $42/month.
Customer-facing checkout and payment tools: PCI compliance, fraud detection, and payment processor relationships are not worth replicating. Keep paying for Stripe, ThriveCart, or whatever handles your payments.
Analytics and tracking: the engineering time to maintain a reliable analytics infrastructure is significantly more expensive than the SaaS alternative for any business under $1M/year in revenue.
The break-even math: replacing a $37/mo Leadpages with a custom build costs $3,700 to $5,700 in year one (build + maintenance). Leadpages costs $444/year. Replacing a $300/mo tool costs $4,500 in year one, saves $2,100/year from year three onward. Only build your own tools when the SaaS costs more than roughly $150/mo and the tool is internal-use with low reliability requirements.
The Honest Verdict
Vibe coding is genuinely useful for internal tools, one-off automations, and custom solutions for problems the SaaS market doesn't solve well. It's a bad decision for customer-facing infrastructure, tools with reliability requirements, and replacements for SaaS products priced under $100/month where the build cost doesn't recover for two or more years.
The Reddit posts about cancelling $800/month in SaaS are usually written by people who replaced three or four tools in the $50 to $200/month range, did the build work on weekends as a hobby, and don't account for maintenance time in the math. The math looks different when your time has a dollar value.