4.9 Based on 12 audits
Your AI wrote the code.
We make it production-grade.
Your Cursor/Bolt/Lovable backend shipped fast. Now it's breaking in prod. We rescue it. Async, fixed price, no calls.
We fix code generated by
Cursor
Bolt.new
v0
Copilot
Claude
Lovable.01
Your AI wrote the code.
Who's gonna fix it?
Your AI wrote 10,000 lines. You understood maybe 200. It worked on localhost. Production is a different game.
Supabase RLS wide open
Anyone can read and write your entire database
Auth that breaks on edge cases
Session hijacking, broken redirects, no token rotation
Secrets hardcoded in the repo
API keys, DB credentials pushed to GitHub
Zero error handling
Unhandled promises, no retries, silent failures
No rate limiting or validation
Open door for abuse, injection, and DDoS
"It works" ≠ "It's ready"
Localhost passes. Production breaks at 50 users
You hired a freelancer to fix it. They added more AI-generated patches on top of AI-generated code. Now it's 2x messier, 3x more fragile, and you're out $3K.
45% of AI-generated code has exploitable vulnerabilities.
Your MVP is a ticking bomb. Every day without an audit is a day closer to a breach.
Source: Stanford University, "Do Users Write More Insecure Code with AI Assistants?" (2023)
Full report in 3-5 business days. No calls required.
.02
Senior engineers + AI tools.
Same stack, different judgment.
Same tools, senior judgment
We use Claude Code, Cursor, Copilot — same tools you do. The difference: 7+ years telling us when the output is wrong.
You buy, we deliver
Your code, your repo. We leave, it keeps running. Any dev can pick up where we left off.
No meetings. No proposals.
No account managers. Linear + GitHub + Loom. That’s the whole workflow.
.03
Pick your fix.
Fixed price. No calls. Cancel anytime. Your code is always yours.
Vibe Code Audit
Instant start“Is my vibe-coded app going to break?”
Before scaling, fundraising, or hiring
Full codebase audit for AI-generated code (≤40K LOC). Security vulnerabilities, architecture gaps, RBAC review, tech debt map, 30-60-90 day roadmap.
- PDF/Notion report + Loom walkthrough (20-30 min)
- 3-5 business days
- Async (Loom + email)
Rescue Sprint
Instant start“My app IS breaking. Fix the critical stuff.”
Urgent production stabilization
Surgical 2-week intervention. CI/CD setup, Supabase securitization, auth middleware, scattered logic refactor. Zero UI/UX — backend only.
- Production-ready code + CI/CD + docs + deploy
- 1-2 weeks (strict)
- Async (Linear + Loom + GitHub)
Build Sprint Standard
Discovery call“I need a real MVP, not a prototype.”
Founders ready to launch
Full-stack MVP from zero to production. Auth, payments, core features, deploy. Functional UI with component libraries — not pixel-perfect design.
- Next.js + Stripe + Auth — deployed & functional
- 4-6 weeks
- Async (Linear + Loom + GitHub)
Build Sprint Complex
Discovery call“My product needs real architecture, not just CRUD.”
Complex SaaS builds
Complex MVP with integrations, multi-tenant architecture, advanced business logic, third-party APIs. Production-grade from day one.
- Multi-tenant + integrations + advanced logic
- 4-6 weeks
- Async (Linear + Loom + GitHub)
Crew
Instant start“Keep my architecture healthy as I grow.”
Ongoing protection, not building
Ongoing architecture guardian. 1 active request at a time. Tasks ≤4h. Code reviews, server monitoring, async architecture support. Not feature building.
- Continuous code reviews + fixes via GitHub PRs
- Ongoing (48-72h per request)
- Async (Linear + Loom + GitHub)
Only 2 of 3 Crew spots available. We take max 2 sprints per month.
.04
How it works
From checkout to production-ready code. 100% async.
01
Buy
Pick a plan and pay via Stripe. First PR within 48 hours.
02
Scan & review
We clone your repo, run security scans, and map every issue. You record a 5-min Loom — we handle the rest async.
03
Get report / fix
Audit clients get a full report with a prioritized roadmap. Sprint clients get production-ready PRs merged into your repo.
04
Scale safely
Your backend is solid. Any dev can continue the code. Upgrade to Crew for ongoing protection.
.05
Why Kactuz?
| Kactuz | Freelancer | Agency | Full-time | |
|---|---|---|---|---|
| Monthly cost | $1,999/mo | $3-8K/mo | $10-25K/mo | $8-15K/mo + equity |
| Time to start | 24 hours | 1-2 weeks | 2-4 weeks | 2-4 months |
| Seniority | Senior-level output, always | Varies wildly | Mostly juniors | If you can find one |
| Meetings | Zero (async) | Some | Many | Daily standups |
| Cancel anytime | ✅ | ⚠️ | ❌ | ❌ |
| Code ownership | 100% yours | Usually | Depends | Yes |
| Quality review | Every PR reviewed | None | Maybe | If you set it up |
.06
Our Stack
Modern, battle-tested TypeScript — end to end.
No PHP. No WordPress. No legacy.
| Layer | Technology |
|---|---|
| Language | TypeScript (end-to-end) |
| Frontend | Next.js / React |
| Backend | Fastify / NestJS / Next.js API Routes |
| ORM | Prisma |
| Database | PostgreSQL / Supabase |
| Auth | Better Auth / Supabase Auth / Clerk |
| AI | OpenAI GPT-4o / Claude / Vercel AI SDK |
| Payments | Stripe |
| Messaging | WhatsApp Business API / Twilio |
| Background Jobs | Trigger.dev / BullMQ |
| Infra | AWS / Vercel / Railway / Docker |
| CI/CD | GitHub Actions |
.07
Founders trust us with their backend.
“Our Supabase RLS was wide open. Kactuz found 14 critical vulnerabilities in 3 days. We would have been breached within weeks.”
SaaS Founder
$2.4M ARR, HealthTech
“We spent 2 months trying to fix our auth flow internally. Kactuz rebuilt it in 10 days. Token rotation, session management, the works.”
Technical Co-Founder
Series A, FinTech
“Went from Cursor prototype to production MVP with real multi-tenant architecture. Our investors were impressed with the code quality.”
Solo Founder
Pre-seed, B2B SaaS
Client details anonymized. Real results from completed engagements.
.08
Before & After
Real projects. Real diffs. From broken to production-grade.
Before
Lovable-generated SaaS with 28K LOC. Founder about to raise Series A. No idea what's broken under the hood.
After (4 days)
Full audit report: 9 critical vulns, 14 high-priority issues, tech debt map, 30-60-90 day roadmap. Investor deck updated with remediation plan.
Pre-Series A HealthTech SaaS
Stack: Next.js, Supabase, Prisma
Before
Cursor-generated monolith with hardcoded secrets, no auth middleware, Supabase RLS disabled, zero CI/CD. Breaking at 50 concurrent users.
After (2 weeks)
Better Auth + RBAC, row-level security enforced, secrets in env vars, GitHub Actions CI/CD, Sentry monitoring. Handling 2K+ concurrent users.
Multi-tenant B2B SaaS
Stack: Next.js, Supabase, Prisma, Stripe
Before
Figma mockup + scattered Bolt.new prototypes. No backend, no auth, no payments. Founder stuck for 3 months.
After (4 weeks)
Production MVP: Next.js + Better Auth + Stripe subscriptions + multi-tenant dashboard + CI/CD + monitoring. Live and accepting payments.
Marketplace SaaS Platform
Stack: Next.js, Fastify, Prisma, PostgreSQL, Stripe
Before
Post-launch SaaS growing 20% MoM. No one reviewing PRs. Tech debt accumulating. 3 incidents in 2 weeks from unreviewed Copilot code.
After (3 months ongoing)
Every PR reviewed within 48h. Architecture guardrails in place. Zero production incidents. Founder ships features without worrying about the backend.
Growing EdTech SaaS
Stack: Next.js, NestJS, Prisma, PostgreSQL, AWS
.09
FAQ
Backend fixed? Now add AI features to your product.
RAG pipelines, AI agents, embeddings, conversational UIs — we ship production-grade AI features in 4-6 weeks.
Hey, I'm Gustavo. 👋
I founded Kactuz after 7+ years building fintech platforms, marketplaces, and SaaS infra. 15+ products shipped.
In 2025, I watched the vibe coding wave explode. Founders shipping MVPs in hours with Cursor and Bolt. Beautiful frontends. Broken backends. Leaking data. Zero auth.
So we built the cleanup crew. Same AI tools, senior judgment on top. No calls, no BS — just code that works in production.
If your backend is on fire, we can help. If it's not on fire yet, get an audit before it is.
Gustavo Henrique
Founder, Kactuz · Belo Horizonte, Brazil 🇧🇷