Impress employers and recruiters.
Choose from hundreds of resume examples.

Target Resume Now

Tailor your resume to this Lead Java Developer/Solution Architect (6-month contract) role.

Rezi rewrites your resume against gravity9's job description. Free.

Resume score gauge reading 58 out of 100

Don't guess if your resume is good enough.

See how it scores against the Lead Java Developer/Solution Architect (6-month contract) posting at gravity9 — free, in seconds.

About the Role

gravity9 is recruiting Java engineers and architects for large-scale, data-intensive modernization programs within UK central government. These roles involve replacing legacy systems, decomposing monoliths, and building secure data platforms. We are hiring for Senior Java Developer and Application / Migration Architect profiles, with opportunities to move between programs.

Responsibilities

Produce high- and low-level designs, security and data architectures, and architecture decision records, and take them through client design authorities and formal governance gates.
Make and defend architectural trade-offs in front of both engineering and non-technical stakeholders, including client technical authorities and third-party suppliers.
Analyze real access patterns and validate target MongoDB document models against genuine throughput, query and sharding requirements before they are baselined.
Design integration boundaries in multi-vendor programs where you own one component and must collaborate across the seams of others.
Build production Java services and RESTful APIs (Spring Boot or similar), designed for integration by multiple consuming systems and documented to OpenAPI.
Design and implement MongoDB document models, aggregation pipelines, indexing and sharding strategies, and integrate them cleanly into Java service layers.
Build data pipelines: CDC and streaming ingest, transformation frameworks, checkpointed batch extract workers, and MongoDB sink configuration and tuning at terabyte scale.
Implement access control, encryption and audit within the application and data layer, including enforcement inside the MongoDB query path.
Write unit, integration, golden-record fixtures, parallel-run reconciliation, and load and stress tests.
Work across both MongoDB Atlas and Enterprise Advanced, including Kubernetes-hosted deployments, and with the migration and sync tooling around them.
Model relational, XML or other legacy schemas onto MongoDB document models, handling schema and semantic drift through versioned, configuration-driven mappings.
Design and prove cutover mechanisms — dual-write, backfill, reconcile, read-switch, rollback — for systems where a failed migration is not an acceptable outcome.
Build validation and reconciliation tooling that satisfies audit: completeness, field-level fidelity, and query-level equivalence between old and new.
Design and implement attribute- or role-based access control models, including enforcement at the data layer and policy administration.
Work with application-layer and field-level encryption — MongoDB client-side field level and queryable encryption, and externally managed key material.
Produce tamper-evident audit trails and observability that answer not just what happened but why.
Work as an embedded member of a small delivery team, frequently alongside client engineers and other suppliers.
Run workshops, playbacks and sprint demonstrations; produce design documentation, integration guides and operational runbooks.
Support knowledge transfer and upskilling of client teams.
Use AI-assisted engineering tooling as part of normal delivery, within the constraints client security policy sets.

Requirements

Strong hands-on Java — building and running production services and RESTful APIs with Spring Boot or an equivalent framework.
MongoDB — solid working experience covering document modelling, querying, aggregation pipelines and indexing, and integrating MongoDB into Java application layers. Atlas and/or Enterprise Advanced.
Data-intensive systems — demonstrable experience of pipelines, migrations or integrations at meaningful scale, and sound reasoning about throughput, ordering, idempotency and failure recovery.
API design — clean, well-documented REST interfaces suitable for integration by multiple consuming systems.
Testing — genuine automated testing discipline, plus practical experience of load and stress testing against realistic volumes.
Infrastructure and deployment — Terraform or equivalent infrastructure as code, containerised deployment on Kubernetes, and AWS or a comparable cloud.
Communication — able to write clear design documentation and hold your own in a client design authority or architecture review.
UK resident, and either holding current UK SC clearance or clearly eligible to obtain it.
Proven design authority on a delivery of comparable size and sensitivity, while remaining hands-on enough to prototype, pair and review code (for architect-level roles).
Experience operating inside multi-vendor or multi-supplier programmes, including holding a technical position when other suppliers hold a different one (for architect-level roles).

Skills

Java
Spring Boot
RESTful APIs
MongoDB
Document Modelling
Querying
Aggregation Pipelines
Indexing
Data Pipelines
CDC
Streaming Ingest
Transformation Frameworks
Batch Extract
Access Control
Encryption
Audit
Testing
Unit Testing
Integration Testing
Load Testing
Stress Testing
Terraform
Kubernetes
AWS
API Design
OpenAPI
Kafka
Debezium
Stream Processing
Strangler Fig Pattern
Operational Data Layers
Dual Running
Phased Cutover
Domain-Driven Design
Bounded Context Analysis
Monolith Decomposition
Attribute-Based Access Control
Policy-as-Code
OPA
Casbin
XACML
Field-Level Encryption
Client-Side Encryption
Key Management
HSM
KMS
KMIP
Search
Lucene
Atlas Search
Vector Search
RAG
Metadata Standards
DCAT
Dublin Core
Data Cataloguing
Data Mesh
Federated Data Architecture
Event-Driven Architecture
Saga Pattern
Eventual Consistency
Oracle
COBOL
Mainframe
Time-Series Data
Geospatial Data
Edge Hardware
AI-Assisted Development
Agentic Coding Tools

Location

Work Type

Engagement Contract
Remote
Hybrid
Part-time
Full-time

Experience Level

Senior
Architect

About the Company

gravity9 is recruiting for a portfolio of engagements across UK central government.
These are large-scale, data-intensive modernisation programmes.
Work is typically delivered through client-supplied devices or VDI, with VPN access to client environments.
Comfortable operating within defined information-handling and access constraints, and with the pace that government security and onboarding processes set.
Small, focused, multi-disciplinary teams.
On several programmes gravity9 delivers alongside partner organisations and other suppliers, and you will need to work effectively across those boundaries.
These roles support a growing pipeline of central government work.
Some engagements are contracted and mobilising; others are in contract negotiation with expected start dates in the coming months.
We are building the bench now so that we can mobilise quickly, and clearance lead times mean early conversations are worthwhile even where a start date is not yet fixed.