What happens after the first 30 days?

You decide whether to continue, and everything delivered on day 30 is yours to keep. The plan already sizes every remaining slice from your code and puts them in order, so the full modernization runs as a series of the same steps: each later slice is sized from your code, some bigger than the first, built by your team or by ours, and each is accepted at its own parity gate. From month two you can keep the platform on a per-system license at list price, so the system map, requirements, and evidence stay in one place as the remaining slices are delivered. It is optional.

Do we have to use the ModernPath platform?

No, you decide. With your agreement the slice runs in the engineering OS, which keeps the system map, the requirements, and the evidence as development continues.

How do you know the slice fits in 30 days?

We size it from the code, not from estimates. Give us read access after the scoping call and we map the system and size the candidate slices before you sign, so the offer names a slice that fits. If access comes on day 1, week 1 does the same, and a slice that proves bigger than a month is split or swapped before gate 1. The price does not change.

Do you need access to production?

No. We work with repository access, a build environment, and a masked test database. The rebuilt slice is merged to your branch and running in your staging environment. You deploy it to production.

Who chooses the target stack?

You do. The slice is rebuilt on the stack you have chosen, and the plan for the remaining slices uses the same target.

Where does the platform run, and where is our data processed?

In the EU. By default the platform runs in the cloud, in the EU. If you can't use a cloud service yet, for example while a security review is pending, a developer can run the same process locally on their machine.

Which coding harness and models are used?

We provide the coding harness (Claude Code, Codex, or Cursor) and the model endpoints as part of the First Slice. If your policy requires your own subscriptions or specific endpoints, for example EU endpoints, we use those instead. We agree this at the scoping call.

First Slice

Modernize one slice of your legacy system in 30 days

Modernization overruns when attempted all at once. We do it one bounded slice at a time: mapped from its code, rebuilt with coding agents, proven by tests, and accepted at a parity gate.

Book the scoping call See how the 30 days work

The mapping step is already in production at Lemonsoft

Your system, mapped

Slice 1

30 days

3 GATES

Slice 1, done

Your legacy system, mapped from its code

Your system, mapped

Slice 1

Screens, endpoints, flows, stored procedures, tables

30 days

GATE 1GATE 2GATE 3

3 GATES

Every remaining slice sized from its code

Slice 1, modernized

Slice 1, done

Rebuilt on your target stack
Tests green, on record
Accepted at the parity gate
Merged to your branch, running in your staging

Modernization plan

Rebuilt on your target stack
Tests green, on record
Accepted at the parity gate
Merged to your branch, running in your staging

Tap or hover a slice or a gate to see what happens to it.

Our approach

A model of your system, and a process that repeats

Modernizations overrun because nobody can say what the legacy system actually does. We start from the code, prove how each slice behaves, and run every slice the same way. The First Slice is how you start.

A domain-driven model of your system

The Knowledge Core maps your code into domains, capabilities, and business rules, each cited to its source.

Parity proven before anything changes

What each slice does is recorded in the Ledger and pinned by parity tests before it is rebuilt.

The same process, slice after slice

Every slice runs through the same gates, so the whole modernization becomes a series of accepted steps.

How we approach legacy modernization

How it works

4 weeks, 3 gates

Build and test run in the agreed coding harness (Claude Code, Codex, or Cursor). Every other step runs in the Agentic Engineering OS.

WEEK 1

Map and choose

WEEK 2

Define and baseline

WEEK 3

Rebuild and test

WEEK 4

Accept and plan

The slice is chosen

Gate 1

requirements and specs

Gate 2

implementation

Gate 3

parity accepted

In the platform

Map the system

Size every candidate slice

Parity baseline

Requirements, cited to source

Parity acceptance

Plan every remaining slice

In the coding harness

Parity tests

Against your test data

Rebuild on the target stack

Tests before code, then merge

WEEK 1
Map and choose
The slice is chosen
- Map the system. Size every candidate slice
WEEK 2
Define and baseline
Gate 1requirements and specs
- Parity baseline. Requirements, cited to source
- Parity tests. Against your test data
WEEK 3
Rebuild and test
Gate 2implementation
- Rebuild on the target stack. Tests before code, then merge
WEEK 4
Accept and plan
Gate 3parity accepted
- Parity acceptance. Plan every remaining slice

The slice is sized from the code before the build starts: during scoping if we have access, otherwise in week 1. If it is bigger than a month, we split it or swap it before gate 1.

What you get on day 30

System map and documentation

From your code, every statement cited to source.

Parity tests

Green on your test data, evidence in the Ledger.

The slice, rebuilt

Merged to your branch and running in your staging environment, parity proven on your test data. You deploy to production.

A modernization plan

Every remaining slice sized from your code, in order.

Customer case card: the codebase AI couldn't read. How Lemonsoft made a mature ERP codebase legible to coding agents.

The mapping step, in production

“A step change in how effectively our developers can work with AI tools.”

Janne Tammi, CTO, Lemonsoft

Every AI session at Lemonsoft started from zero. Mapping its ERP codebase into a model that coding agents can query changed that.

Read the Lemonsoft story All customer stories

Price and scope

What is included, and what it costs

A forward deployed engineer

Runs the platform and pairs on the build.

The platform for the month

Knowledge Core, Ledger, Mission Control, and hooks for the agreed coding harness. Runs in the cloud, in the EU; if you can't use a cloud service yet, a developer can run it locally. AI usage, coding harness, and model endpoints included.

To start, from you

Repository access, a build environment, a masked test database, a staging environment to deploy to, and a business owner. Final acceptance of the slice is yours.

First slice, month one

€10,000 fixed

Excluding VAT

One slice, sized from your code before the build starts.

Every slice after

Sized from your code

Some fit the same four weeks, some are bigger. Each runs the same three gates, built by your team or by ours.

What a slice is

A set of screens, endpoints, jobs, and reports whose behavior we can prove on your test data within a month.

Slices follow the domains and sub-domains in the map of your system, so each owns its tables, every integration can be stubbed with a contract test, and it can be routed to on its own. It is rebuilt and accepted without touching the rest of the system. We size it by what has to be verified and decided, not by code volume. Later slices are sized from the code and can be bigger than the first.

Not in month one: framework, runtime, or database upgrades outside the slice; integration migrations; more than one slice; production data extraction. The agreed coding harness runs the tests; the platform records the evidence. Ledger artifacts are exportable.

Questions

Book the scoping call

We name the slice, the dates, and the owner in 1 hour

Pasi Vuorio

CEO

Gaurav Khullar

CPO

Pick a time that suits you

1 hour with a founder. Slots come live from our calendar, and you get a confirmation invite immediately. Give us read access after the call and we size the candidate slices before you commit.

Day

Time (Helsinki)

Checking the calendar…

The Cognitive Split Hypothesis, whitepaper cover

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