Show HN: I built a finance app for couples after 9 years of Google Sheets

2 craigbanach 0 9/8/2025, 9:51:37 PM craig.banach.dev ↗

After tracking finances in Google Sheets since 2016 (currently at column XE - 657 columns), I finally built the app my wife and I needed. The breaking point was yet another argument about a forgotten Amazon purchase that broke our budget.

personifi is intentionally simple - real-time sync between partners, individual logins with shared data, and transaction entry that takes 12 seconds on mobile. Built with Next.js, .NET, and Postgres, running on a €4.55/month Hetzner VPS with Nomad orchestration.

The most validating moment: my wife told me she actually prefers it to our spreadsheet. After 9 years of her tolerating my spreadsheet obsession, that's worth more than any metric.

Currently at 2 DAU (us), but opening it up at £4.99/month for couples who want to stop arguing about money. Also included our free Google Sheets template if you prefer that route.

Blog post about building it: https://craig.banach.dev/musings/i-built-an-app App: https://personifi.xyz

Happy to answer questions about the technical stack, the couples-first approach, or why I chose Nomad over K8s for orchestration.

Mistral AI raises 1.7B€, enters strategic partnership with ASML (mistral.ai)

A clickable visual guide to the Rust type system (rustcurious.com)

You too can run malware from NPM (I mean without consequences) (github.com)

The Last Programmers (xipu.li)

How can England possibly be running out of water? (theguardian.com)

Signal Secure Backups (signal.org)

Nango (YC W23) Is Hiring a Staff Back End Engineer (Remote) (jobs.ashbyhq.com)

DuckDB NPM packages 1.3.3 and 1.29.2 compromised with malware (github.com)

Hallucination Risk Calculator (github.com)

Liquid Glass in the Browser: Refraction with CSS and SVG (kube.io)

iPhone dumbphone (stopa.io)

Strong Eventual Consistency – The Big Idea Behind CRDTs (lewiscampbell.tech)

No adblocker detected (maurycyz.com)

NPM debug and chalk packages compromised (aikido.dev)

Experimenting with Local LLMs on macOS (blog.6nok.org)

Contracts for C (gustedt.wordpress.com)

Microsoft doubles down on small modular reactors and fusion energy (techradar.com)

The elegance of movement in Silksong (theahura.substack.com)

Alterego: Thought to Text (alterego.io)

Anscombe's Quartet (en.wikipedia.org)

Is OOXML Artifically Complex? (hsu.cy)

Deluxe Paint on the Commodore Amiga (stonetools.ghost.io)

CPR in space could be made easier by chest compression machines (newscientist.com)

Will Amazon S3 Vectors kill vector databases or save them? (zilliz.com)

Clankers Die on Christmas (remyhax.xyz)

Show HN: Attempt – A CLI for retrying fallible commands (github.com)

Seedship – Text-Based Game (philome.la)

The key points of "Working Effectively with Legacy Code" (understandlegacycode.com)

AMD claims Arm ISA doesn't offer efficiency advantage over x86 (techpowerup.com)

Ask HN: Good resources for DIY-ish animatronic kits for Halloween?

I have left Branch and am no longer involved with Nova Launcher (teslacoilapps.com)

Jeena's Hyprland Demo (tube.jeena.net)

Byte Type: Supporting Raw Data Copies in the LLVM IR (blog.llvm.org)

The Storm Hits the Art Market (news.artnet.com)

How Britain built some of the world’s safest roads (ourworldindata.org)

Learning the soroban as an adult (2022) (github.com)

AI might yet follow the path of previous technological revolutions (economist.com)

Ex-WhatsApp cybersecurity head says Meta endangered billions of users (theguardian.com)

A critique of package managers (gingerbill.org)

Show HN: ZeroFS, the Filesystem That Makes S3 Your Primary Storage (github.com)

Immich – High performance self-hosted photo and video management (github.com)

Why is Japan still investing in custom floating point accelerators? (nextplatform.com)

Interview with Geoffrey Hinton (ft.com)

A formal proof that AI-by-Learning is intractable (link.springer.com)

Dark Academia Grows Up (publicbooks.org)

MileSan: Detecting μ-Architectural Leakage via Differential HW/SW Taint Tracking (comsec.ethz.ch)

OpenWrt: A Linux OS targeting embedded devices (openwrt.org)

David Walker's Paper Clip Collection (presentandcorrect.com)

ATC/OSDI '25 Joint Keynote: Accelerating Software Dev: The LLM (R)Evolution [video] (youtube.com)

Job mismatch and early career success (nber.org)

Show HN: I built a finance app for couples after 9 years of Google Sheets

Comments (0)