Flexipy
Industries · Services · Products

Flexipy OÜ · Python engineering · Estonia, EU

Software that outlives its MVP.

Founders reach us six months in, holding code nobody can maintain. We take it over, make it safe to change, and ship the next release — or build the new system properly the first time. You get a fixed-price roadmap within a week, working software you can click every week after, and the engineer who designs yours is the one you talk to.

10+ years
shipping production Python
6+ years
longest client relationship
01 Products we built and operate

Products we built, and still operate

Not case studies we can't show you. Working software, with the engineering problem named.

Dev13 Systems

2025

The operating system an agency runs on, with AI built into the data rather than bolted beside it. CRM through to cash — accounts, deals, proposals, contracts — then native projects with work items, cycles and worklogs, HRM and payroll records, a multi-currency finance module built on a service catalogue, plus LMS, recruitment, OKRs, a wiki and a client portal. Twenty-five specialist agents across sales, delivery, engineering, marketing, talent and internal ops work over the same organisation-scoped store, so an agent answers from the agency's own accounts, projects and documents instead of from a chat window that knows nothing about them.

What was technically hard

Twenty-five agents reading one knowledge base, none of them able to see across a tenant boundary. Retrieval is scoped at the query layer — the organisation is an argument to the search, not a filter applied to results afterwards — and the isolation is enforced again underneath by Postgres row-level security, because a filter you forget is a data leak and the second line has to hold when the first is wrong. Money made it harder still: every amount is a value object carrying its currency and the FX rate captured at transaction time, so a figure stays true to the day it was recorded rather than to today's rate.

XBuilder

2025

An AI takeoff platform for construction estimating. It reads a PDF floor plan and returns structured quantities — rooms with areas and perimeters, openings with widths and heights, dimension chains and building sections — which an estimator exports as CSV or JSON and bids from, instead of measuring the drawing by hand.

What was technically hard

A language model returns plausible JSON, not a schema. Plans name their levels inconsistently, quote dimensions in whatever the drafter used, and omit fields entirely, so nothing from the model is trusted directly: every number is coerced before it becomes a row, levels are derived from the floor map rather than read off the labels, and every room and opening carries its own confidence score. An estimator prices a bid off these figures, so a wrong number that looks certain is far worse than one marked uncertain.

Osvitly

2026

A multi-tenant school platform where any teacher or school gets an isolated workspace of their own. Lesson planning with media, tests and question banks, homework with media submissions, attendance, a gradebook, class projects with teams, messaging and announcements, and a shared library — with parents given read access to their own children's progress and a line to the teacher. A single tutor running a school of one is a first-class case rather than a workaround, and one account can hold different roles in different schools. English and Ukrainian throughout, with AI help for building lesson content over an MCP server.

What was technically hard

A gradebook has to be honest about a term that is only half finished. The naive version divides by everything planned, so a pupil three weeks into a course reads as failing, and a parent who sees that number acts on it. Totals here accumulate only the items a pupil actually has a grade for; attendance is measured against lessons that were actually marked, so an unrecorded lesson never counts against anyone and an excused absence never punishes. The other half was making it fast: every gradebook view assembles from a fixed number of queries no matter how many pupils are in the class, and a test guards that count so a later change cannot quietly reintroduce a per-pupil lookup.

02 Selected work
03 Industries we know
04 How we work

A fixed-price roadmap in a week, then working software every week after

Fixed price, weekly demos. A typical build is 8–16 weeks to the first production release.

  1. 01

    Discovery call

    Free. We work out what you actually need built.

  2. 02

    Fixed-price roadmap

    Within a week. Scope, sequence and cost, in writing.

  3. 03

    Weekly working demos

    Not status reports — software you can click.

  4. 04

    Tested, secure launch

    With the tests and the deployment you keep.

  5. 05

    30 days support

    After launch, included.

05 Build or buy

When you should not hire us

If an existing product fits your process, buy it. Here is how we think about the choice.

Bespoke software compared with Off-the-shelf SaaS

Dimension

Building it

When Off-the-shelf SaaS works

Fit to your process Built around how you actually work, including the parts that are unusual. Fits if your process is close to the industry norm — and many are.
Time to first value Weeks. Nothing works until the first release. Days. This is the real advantage, and it is a big one.
Ongoing cost You own the code and pay to maintain it. Per-seat forever, but somebody else carries the maintenance.
Integrations Whatever you need, including the internal system nobody else has. Whatever the vendor supports. Check before you commit.
When it breaks You decide the priority, because it is your team. You file a ticket and wait with everyone else.
Leaving The code and the data are yours. Export what the vendor lets you export.
06 What clients said

Every quote here links to where you can check it

Stanislav demonstrated deep technical acumen during his time as a Technical Lead at Integrity Lab, consistently identifying critical areas for code base improvement and implementing effective solutions. His experience with engineering and team processes helped lay groundwork for our efforts to scale the team.

CTO · Integrity Lab

Patrick S.verify ↗

He demonstrated a strong understanding of Django, Django Admin, and backend architecture, and was able to quickly get up to speed with an existing production system. His Python skills are solid, communication was clear on both technical and business topics, and tasks were delivered reliably. Overall, a professional and dependable developer.

Internal gas trading platform · Python, Django, AWS

Verified Upwork clientverify ↗

He worked fast and with high quality. I appreciated his thoughtful planning approach. He shared his architectural approach and asked for feedback on that early on, which helped move the project along smoothly. His communication skills were great (spoken, written, demeanor). Super easy to work with.

Quoting app automation · Django, React, Docker

Verified Upwork clientverify ↗

I highly recommend working with Stan — he ramped up on our complex multi-agent AI architecture remarkably fast, understood the full project structure within days, and played a key role in delivering on our launch deadline. Reliable, sharp, and a clear communicator.

Multi-agent AI platform · Delivered to launch deadline

Verified Upwork clientverify ↗

Stanislav was responsible for building out the entire backend infrastructure using Python, Django, Django REST Framework, PostgreSQL, Celery, Redis, all containerized with Docker and Docker Compose and deployed on a VPS. He moved through the development work very fast without cutting corners. I would not hesitate to work with Stanislav again and would recommend him to anyone looking for a dependable, skilled backend developer.

M-JIBU, SMS-to-AI assistant · Kenyan market, M-PESA and Africa's Talking

Verified Upwork clientverify ↗

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Stanislav Rybonka · Founder & Principal Engineer

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