What Would I Actually Use My Own Webapp For?
After building a simple auth system, I asked: what's genuinely worth building? Here's what I found.
I just spent a week debugging oauth2-proxy. CSRF tokens, cookie domains, redirect loops — the whole authentication nightmare. In the end, I ripped it out and built a 200-line Go webapp with simple username/password auth.
Now I have a working authenticated webapp at agents.ch3ngl0rd.com/app. Friends can sign up with invite codes. The auth is simple, reliable, and I actually understand how it works.
But here’s the question: what would I actually use this for?
I asked Codex to research genuine value-add use cases. Here’s what I found.
The Insight: SaaS Tools Fragment Your Life
The problem with using Splitwise for expenses, Notion for notes, Day One for journaling, and Doodle for planning is:
- Your data lives in silos — Your expenses don’t talk to your journal entries
- You hit paywalls — Splitwise Pro, Notion Team, Day One Premium
- You’re the product — Free tiers mean your data is being sold
- No integration — Each tool is a walled garden
When you own the infrastructure, you can build tools that actually integrate with your life.
The Top 6 Ideas (Ranked by Value)
1. FlatOps Ledger — Shared House Money
What it is: A single place for rent, utilities, internet, groceries. Who paid what, who owes whom, monthly settlement snapshots.
Why it’s better than SaaS: Splitwise free tier has limits and pushes Pro. Your app can be zero-paywall and tailored to your exact house rules. No ads, no upsells.
Complexity: Medium (1-2 weeks)
Why it fits me: I’m moving into a Glebe apartment with 2 close friends. We’ll have shared expenses from day one. This has immediate weekly value.
The gap in the market: Most expense-splitting apps are mobile-first, ad-supported, or paywall-gated. A simple web app with invite-only access for close friends is exactly what’s missing.
2. Decision Room — Availability + Voting + Commitment
What it is: Plan dinners, trips, house purchases with clear “who can do what when.” Availability polling, budget caps, and final decision logs.
Why it’s better than SaaS: Doodle-style polling is generic and often paid for team features. Your version can combine availability, budget constraints, and decision history in one place.
Complexity: Small-Medium (4-10 days)
Why it fits me: Coordinating with friends for events, dinners, and house decisions is a recurring friction point. Having a dedicated space for “let’s figure this out” would reduce group chat noise.
The gap: Existing tools are either enterprise-focused (Calendly, When2meet) or mobile-only. A simple web interface for close friends is underserved.
3. Journal Intelligence — Pattern Extraction from Daily Entries
What it is: Turn daily journaling into trend views. Mood/energy/social/spend/workload correlations over time.
Why it’s better than SaaS: Journal apps are usually personal-only, device-limited, or premium-gated. Your system can integrate life data (expenses, events, decisions) directly into your reflection practice.
Complexity: Medium (1-2 weeks)
Why it fits me: I journal daily. This is already a habit. Adding intelligence on top would compound the value of every entry.
The gap: Day One, Journey, and others focus on the writing experience, not the insight extraction. A tool that surfaces patterns from your own data is rare.
4. Hugo Publishing Pipeline — Private Draft → Public Post
What it is: Write raw notes privately, auto-propose sanitized blog drafts for agents.ch3ngl0rd.com. Privacy-first staging before publishing.
Why it’s better than SaaS: No context switching across Notes/Notion/blog CMS. Your private thoughts stay private until you choose to publish.
Complexity: Small (3-7 days)
Why it fits me: I already run Hugo and publish content. This would streamline the workflow from “idea in my notes” to “published blog post.”
The gap: Most CMS tools are either all-public (WordPress) or all-private (Notion). A staging workflow that respects privacy boundaries is missing.
5. Sydney Life Console — Transport/Events/Cost Radar
What it is: Curated Sydney feed. Commute changes, saved places, recurring local events, monthly city spend view.
Why it’s better than SaaS: Generic city apps don’t unify your personal routines and friend-house context. This would be a dashboard for your Sydney life.
Complexity: Medium-Large (2-4 weeks depending on API depth)
Why it fits me: Moving to a new city for a new job. Having a personalized “operating system” for Sydney would accelerate my onboarding.
The gap: Transport apps show schedules, not your commute patterns. Event apps show everything, not what matches your interests. A unified personal console doesn’t exist.
6. Learning Loop — Work Notes → Spaced Recall
What it is: Capture backend lessons, system-design snippets, and auto-generate review cards from real work notes.
Why it’s better than SaaS: Anki/Notion are disconnected from your daily workflow. This would derive prompts directly from your actual entries.
Complexity: Medium (1-2 weeks)
Why it fits me: Early-career acceleration at TikTok. Strong compounding payoff for skill development.
The gap: Spaced repetition tools require manual card creation. A system that generates cards from your natural work notes would be a game-changer.
What’s Uniquely Strong About Owning Your Infrastructure
| Aspect | SaaS | Your Webapp |
|---|---|---|
| Data ownership | Their servers | Your server |
| Integration | Walled gardens | One data model |
| Pricing | Per-seat, per-feature | Zero marginal cost |
| Trust boundary | Public signup | Invite-only for friends |
| Longevity | Company could shut down | You control it |
The Recommendation
If I had to pick one to build first: FlatOps Ledger + Journal Bridge.
Here’s why:
- Immediate utility — I’m moving in with friends next month
- Weekly usage — Expenses happen constantly
- Integration opportunity — Link expenses to journal entries (“why did I spend $200 on dinner?”)
- Compounding value — Every month of data makes the next month clearer
The second priority would be Journal Intelligence — because I already journal daily, and adding insight extraction would multiply the value of a habit I already have.
The Honest Take
Most people shouldn’t build their own tools. It’s time-consuming, and SaaS exists for a reason.
But if you’re:
- A developer who can maintain a 200-line Go app
- Living with friends and sharing expenses
- Already journaling daily
- Starting a new chapter in a new city
Then building your own infrastructure isn’t vanity — it’s leverage.
You get tools that fit your life, not tools you have to fit your life into.
What would you build if you owned your own authenticated webapp?