Senior Software Engineer (Full Stack)

Who we are

4C Strategies builds organisational readiness and military training management software for clients in over 70 countries. Our flagship product, Exonaut®, is used by NATO and allied forces to plan, run and evaluate exercises in real time. Our consultants and engineers work alongside armed forces across the UK, Europe, North America and beyond to deliver training and exercise management solutions.

What we're building

This role works on Exonaut itself: two applications on one platform.

The first makes exercise assessment traceable. Every judgement about whether a unit is ready traces back through evaluations and observations to the training objective it was meant to test, and that chain holds across exercises and over time. The second coordinates training programmes: dozens to hundreds of exercises, force-generation events and capability activities that compete for the same units, training areas and enablers. We model a programme as a graph of dependencies, so a conflict surfaces before anyone commits to it, not weeks later at a planning conference.

Both run on a meta-model platform that lets one product core serve structurally different national customers. Each customer arrives with its own doctrine, vocabulary and governance, and we absorb that variation as versioned, governed configuration, never as a fork of the code. The hard part is holding that line: keeping the domain model deep and coherent while every customer has a reasonable-sounding case for one more special case.

How we build

Modern Java — currently 25 — on the backend, an Angular and Nx frontend in TypeScript, PostgreSQL, and Liquibase-managed migrations. The platform has years of production use behind it, and we are modernising it in place rather than rewriting it: mainstream frameworks replacing hand-rolled infrastructure one area at a time, an explicit API contract, and business rules in the backend, where they belong.

The principles are conservative on purpose. Evolve, don't rewrite. Configuration over code forks. The domain model carries the load: given the choice between a richer model and shipping sooner with a thinner one, we invest in the model. Governed by default: every element has a visible state, an owner and rules for how it changes. Standardise over hand-roll. Structural decisions are argued in RFCs and recorded in ADRs.

Three constraints shape most of what we do. It runs inside the customer's own environment, on premises and often air-gapped, so nothing may assume a managed cloud service or a route to the internet. Many versions run in the field at once, each upgraded only in a scarce, accreditation-bound window, so every release ships as a self-contained package with a rollback that has actually been tested. And every decision is traceable — who assessed or approved what, when and on what basis — in an audit trail that cannot be rewritten. AI may assist; it never makes the assessment or the decision.

You

You will work across the stack. Substantial experience in either Java or TypeScript, and a genuine willingness to be useful in the other. Opinionated about design, and comfortable arguing a position in writing. Sound judgement about data modelling, because the central questions here are modelling questions: how to represent graph-shaped domains on a platform built for trees, and make them perform at the scale of a six-week campaign. Patience with a codebase that has history, and the discipline to improve it step by step rather than wish it away.

A real advantage, though none of it is required: modernising a mature system in place; graph data modelling or query performance; workflow and state-machine design; on-premises, air-gapped or accredited deployments; or knowing how defence organisations train, exercise and plan. The domain is learnable, the judgement less so.

You'll work alongside product managers, designers and defence specialists who know this domain well. Your designs will be challenged, and you'll be expected to challenge back — including on scope.

Research shows some people only apply when they meet every requirement. If you don't tick every box but recognise yourself in much of the above, please apply anyway. We'd genuinely like to hear from you.

Security and citizenship

This role supports defence work, so the successful candidate must hold Swedish citizenship and pass Swedish security vetting (säkerhetsprövning). We will explain what the check involves early in the process rather than late — a requirement like this should never be a surprise at offer stage.

This requirement comes only from the security rules that govern defence work, not from personal preference.

Why it matters

Deterrence works only when a capability is real, and a capability is only real once it has been trained and tested under conditions close to the ones it would face. When a commander reports that a formation is ready, that judgement has to rest on evidence, not opinion. Exonaut is where that evidence is planned, gathered and defended.

How we hire

Every interview has a written script and a scored rubric, applied the same way to every candidate.

1. Hiring Manager Screen — a conversation about your experience, how you work and what you want next.

2. System Design — a design discussion drawn from problems like the ones above.

3. Programming — a hands-on session in a language of your choice (Java, C#, TypeScript, Python or Go).

4. Culture Interview — how you collaborate, disagree and make decisions with others.

5. Candidate Q&A — your time to interrogate us. We expect you to use it.

We then debrief as a panel and decide. We review applications on a rolling basis.

What you can expect from 4C Strategies

• Based in our Malmö office: we expect you on site four days a week.

• Competitive salary, reviewed annually.

• Occupational pension (tjänstepension).

• Wellness allowance (friskvårdsbidrag).

• Healthcare insurance, including insurance for treatment.

• Parental pay.

• Vaccinations.

• A supportive, collaborative team building meaningful products for mission-critical work.

Why join 4C Strategies

This is a senior role on a product used in earnest, at the point where its platform's next shape is being decided. The direction is set — evolve it, standardise it, model the domain properly — and the people who do that work well are the people who decide how it is done. You'll work alongside experienced engineers and military specialists, with the individual-contributor track valued as highly as management, so you can grow without leaving the code behind.

The work matters: what you build helps armed forces, public safety and resilience organisations train, prepare, and respond.

How to apply

To apply, click the Apply today button and submit your CV. A short cover note on your experience and motivation is welcome but not required. We review applications on a rolling basis, so please apply as soon as you can.

4C Strategies is an equal opportunity employer. We celebrate diversity and are committed to creating an inclusive environment for all employees.