— Practice / 04 / Surface

App Engineering.

Where the leap meets the customer. We modernise legacy estates and build new AI-native products — with a craft bar set where it should have always been.

§ 01
Why this practice exists

The application is the only thing the customer ever sees. Everything else is interior decoration.

Most modernisation programmes confuse motion with progress — re-platform without re-thinking, re-skin without re-architecting. We do not believe in that work.

Our app practice ships products and platforms that pass two tests: customers love them, and engineers want to keep working on them.

§ 02
Capabilities

What we build.

From decade-old monoliths to ground-up agentic products — the same craft, applied differently.

— 01

Application Modernisation

Strangler-fig migrations, monolith decomposition, event-driven re-architecture. Modernisation that ships customer value at every milestone — never a 24-month death-march rewrite.

StranglerDDDEvents
— 02

Platform Modernisation

Internal developer platforms, golden paths, paved roads, Backstage-class portals. The multiplier layer that turns engineering velocity from heroics into compound interest.

IDPBackstagePaved roads
— 03

AI-Native Product Builds

Agentic workflows, copilots that don't suck, retrieval-grounded experiences. Products designed around the model — not bolted onto it as a sidebar feature.

AgentsRAGCopilots
— 04

Developer Experience

CI/CD, preview environments, AI-pair workflows, eval harnesses, ergonomic local stacks. We treat developer time as the asset it is — and design it accordingly.

CI/CDDXEval harness
— 05

Frontend & Design Engineering

Design systems that engineers actually adopt, accessibility as a default, performance budgets that hold. The interfaces your brand deserves.

Design systemsA11yPerf
— 06

API & Integration Surface

OpenAPI-first design, GraphQL federation, event meshes, webhook hardening. The connective tissue that lets the rest of the estate compose.

OpenAPIGraphQLEvents
§ 03
How we engage

Three shapes.

Sized to the work, not to the retainer. We do not staff projects we do not believe in.

— 01 / Strike team

The first wave.

4–8 senior engineers, embedded for 12–24 weeks. Ships the proof point that makes the wider modernisation politically viable.

— 02 / Pod model

Steady-state delivery.

Long-running pods aligned to product surfaces. Quarterly outcome contracts, transparent burn-down, clean handover discipline.

— 03 / Programme lead

Whole-estate modernisation.

Multi-pod programmes with named principals, executive cadence, and an end-of-engagement capability transfer that sticks.

The product is the only thing
the customer ever sees.
— App Engineering at Revoleap
§ 04
Adjacent practices
— 01 / Practice in chief
AI Engineering
Read →
— 02 / Foundations
Cloud
Read →
— 03 / Substrate
Data
Read →
— 05 / Always-on
Platform Ops
Read →

Ship the first wave.

A working session with our app engineering principals — modernisation triage, AI-native product strategy, DX audit.

Begin a conversation
§ 04
Sample artifact · the evals loop that lets AI features ship
— Figure · the loop that lets AI features ship without regression

A system is only as good as the eval set you published.

— THE GATE Eval Held-out set + LLM-as-judge — 01 · DEFINE What good looks like Behaviours, edges, refusals — 02 · BUILD The agent / model Prompts, tools, guardrails — 04 · SHIP Behind a flag Canary, A/B, gradual — 05 · MONITOR In production Drift, prod-eval, signal — REGEN LOOP

— The loop on the left — production observation feeding back into the eval set — is what separates AI you can ship weekly from AI that quietly regresses for two months before anyone notices.