Open for work · one engagement slot free, Q3 2026
Prague · est. 24 May 2016 · IČO 05108438

Agentic software,
shipped with twenty
years of taste
behind every commit.

Banana Pancakes is a one-person Prague studio. Products of its own — Polarix, HOCR, Perdify, Worklist — plus agentic development and audits for teams that need a senior engineer who already knows how the agents behave.

Operator
Jiří Zajpt, managing director
Shipping since
May 2016 — ~10 years
Writing code since
~2005 — ~20 years
Products live
3 live · 1 in beta
Based
Prague 5, CZ — CET
§ 01 — Products

Things I’ve built.

All owned 100% by Banana Pancakes s.r.o. No outside investors.
/ 01 · iOS puzzle game Live · App Store

Polarix

A merge-puzzle iOS game with one mean twist: opposite charges fuse, same types merge up to annihilation. Slide cores, set up chains, survive — three rules, infinite depth.

playpolarix.com Swift · SwiftUI
/ 02 · B2C call-center CRM Live · Sales-led

HOCR

A B2C CRM built around the call center. Sales pipeline, e-sign agreements, Twilio Flex routing, branded customer portal, and AI-driven call QA — one audit-friendly platform, ready to launch in days.

hocr.app Rails · Rust · Twilio Flex
/ 03 · AI interrogation game Beta · TestFlight

Perdify

An AI interrogation mystery for iOS. Six suspects who think, remember, and lie on their own — press them through voice or text, and find the killer before the room turns on you.

Swift · Rails · Postgres
/ 04 · Encrypted task manager Live · worklist.app

Worklist

Zero-knowledge, end-to-end encrypted task management for teams that actually care who sees what. Tasks, comments, delegations, attachments and notes — all encrypted client-side, before they leave the browser.

worklist.app Rust · TypeScript
§ 02 — Open source

Things I’ve given away.

Extracted from real apps. Issues welcome.
/

runledger

Rust PostgreSQL SQLx 4 crates
github.com/featherenvy/runledger

A Postgres-native durable job queue and workflow orchestrator for Rust. Cron schedules, workflow DAGs with dependency counters, idempotent enqueue, dead-letters, panic-aware metrics rollups, and external workflow gates — extracted from a real production app and published as a standalone four-crate workspace.

runledger  ·  workspace
├─ runledger-core            public contracts, traits, types
├─ runledger-postgres        SQLx persistence · queue · DAG
├─ runledger-runtime         worker · scheduler · reaper
└─ runledger-test-support    ephemeral DB harness for tests
§ 03 — Services

How I plug in.

Audits run weeks. Builds run months. Retainer or fixed.
02 / Audit & optimization

Audit & optimization

For teams already running agents but losing speed somewhere. I audit the workflow end-to-end — tools, prompts, evals, models, review process — then rebuild what’s broken and document what works.

01Workflow audit & written report
02Prompt, eval & tooling improvements
03Model selection & routing review
04Team playbook & handover
03 / Growth

Honest growth

Landing pages that load fast and say something true. Paid acquisition with real attribution. I run the numbers and tell you when the spend isn’t working — before you ask.

01Landing pages & A/B testing
02Paid: Google, LinkedIn, Meta
03SEO & technical content
04Attribution & weekly readouts
§ 04 — Recent work

What working with me looks like.

Client name redacted at their request. Engagement active.
~/D/[redacted]
$ find frontend/ admin-panel/ -iname "*.tsx" | xargs cat | wc -l
    78980
$ find crates/ -iname "*.rs" | xargs cat | wc -l
   377899
$ git log --reverse --format="%ai" | head -1
2026-02-13 18:24:49 +0100  # first commit
$ date
Sat Apr 25 22:40:10 CEST 2026
~456k
lines, total
~10
weeks since first commit
1
engineer · agentic
We bet on Banana Pancakes’ agentic development approach and got the work of five engineers in the first month — with the judgment to tell us when we were wrong. Startup speed, senior taste, zero hand-holding. Hire them before someone else does.
Client founder Active engagement · 2026

For twenty years I’ve led teams of developers and shipped products. Running a team of agents across projects asks the same skills. Software ships at breakneck speed now — the challenge is making it correct, and maintainable.

— On running engineers, and agents Jiří Zajpt Managing director & principal engineer, since 2016
2016
founded · 24 May · Prague
~20
years writing software
1
engineer · solo operator
§ 05 — Stack

Tools I reach for.

Languages I’ve led teams in — and lead agents in too.

Principles

Typed where it helps. Boring where it must. Fast where it matters.

Agents are great at volume and terrible at judgment. I pair them with languages whose type systems catch the mistakes agents love to make — Rust, TypeScript, Swift — and keep a clear path back to sanity when they wander.

/ 01Rustbackends · hot paths
/ 02TypeScriptfrontends · tooling
/ 03Ruby on RailsCRUD · backoffice · MVPs
/ 04SwiftiOS · Polarix & Perdify
/ 05Pythonresearch · ML · glue
/ 06Postgresthe database
/ 07Codexprimary driver · Claude for UI
/ 08Grafanabusiness dashboards · alerts
§ 06 — How I work

A short, predictable dance.

Every engagement roughly follows this shape — adjusted, not invented.
Phase 01
First call

45 minutes to understand the business, the team, and what’s on fire. I’ll tell you if I’m the right shop — and if not, who is.

~ 1 week
Phase 02
Written proposal

Scope, cost, timeline — in a short document you can share with a co-founder or a board without explaining it twice.

~ 1 week
Phase 03
Ship & iterate

Weekly demos, a shared Linear board, and a principal who answers Slack. No status-update theatre, no middleman.

3 – 12 months
Phase 04
Handover (or stay)

When the thing is built, I document everything and leave — or stay on a lighter retainer. Your call, not mine.

open-ended
§ 07 — Contact

Tell me what’s broken
or missing.

Short messages are fine. I reply within a working day, in plain Czech or English. No form-letters, no sales cadences — it’s just me.

Signal / Phone
on request
Registered office
Na pomezí 910/2
Jinonice, 158 00 Praha 5
Česká republika
Company
IČO 05108438
DIČ CZ05108438
C 258440, MS v Praze