Why This Role Stands Out
This contract role offers a competitive daily rate of £420 (Outside IR35) for a six-month engagement, focusing on the fascinating challenge of reverse-engineering complex legacy systems and creating essential technical documentation. You'll thrive if you have a proven track record in detailed technical analysis and documentation, and you're eager to contribute significantly to a modernization project. Apply now to leverage your deep technical data skills in this impactful on-site (two days per week in London) position.
Quick Overview
Job Description
Technical Systems Data Analyst - Legacy Application Reverse Engineering
£420 per day - Outside IR35
Initial six-month contract
London - two days per week onsite
We are recruiting a Technical Systems Data Analyst to investigate and formally document a complex, tightly integrated Legacy application and its underlying databases.
This is not a BI, reporting, dashboarding or commercial analytics position. We require someone who has personally reverse-engineered poorly documented applications and databases and produced detailed technical data manuals for use by architects, developers and migration teams.
The assignment
You will analyse the current application and data environment to establish exactly how it operates, how its data is structured and how its different components interact.
Your principal deliverable will be a comprehensive current-state documentation pack covering:
- Database schemas, tables, columns and data types.
- Primary and foreign keys, relationships and constraints.
- Indexes, views, stored procedures, functions and triggers.
- Business rules Embedded within databases, applications and established processes.
- Application-to-database interactions and access patterns.
- APIs, interfaces, integrations and external dependencies.
- End-to-end data flows and data lineage.
- Source-to-target mappings.
- Transformation, cleansing and validation requirements.
- Data-quality issues, risks, assumptions and unresolved gaps.
- Data dictionaries, entity-relationship diagrams and supporting technical documentation.
You will work with technical teams, system owners and business subject-matter experts to validate your findings and ensure the documentation is sufficiently accurate and detailed to support application modernisation, migration and target-solution design.
Essential experience
Applicants must be able to demonstrate recent, hands-on experience of:
- Reverse-engineering a complex or poorly documented Legacy application and its underlying databases.
- Using advanced SQL to interrogate schemas, data structures, relationships and Embedded logic.
- Producing formal current-state data manuals, data dictionaries, ERDs or equivalent documentation packs.
- Documenting tables, columns, keys, indexes, constraints, relationships and dependencies.
- Discovering and documenting business rules rather than simply receiving completed requirements.
- Tracing data across applications, databases, APIs, interfaces and integrations.
- Creating source-to-target mappings and documenting transformation rules.
- Working with relational databases such as SQL Server, Oracle or PostgreSQL.
- Supporting application-modernisation or data-migration programmes.
- Presenting technical findings clearly to architects, developers and non-technical stakeholders.
- Working within structured enterprise governance, traceability and sign-off processes.
Highly desirable
- Migration from a relational database to a document-based or NoSQL platform.
- MongoDB, Azure Cosmos DB, Couchbase or equivalent NoSQL experience.
- Azure data services.
- ETL/ELT and data-transformation experience.
- Data lineage, metadata management and data-governance experience.
- Experience analysing custom-built enterprise applications.
Please note before applying
This role is unlikely to suit candidates whose experience is primarily focused on:
- Power BI, Tableau or dashboard development.
- Reporting and management information.
- Statistical, customer or commercial analysis.
- Data science or machine learning.
- Building cloud data pipelines without Legacy-system investigation.
- Database administration without systems-analysis and documentation ownership.
- Migration delivery where mappings and business rules were supplied by another team.
To be considered, your CV must include a clear example of an application or database that you personally reverse-engineered and the technical documentation or data manuals you produced from that investigation.
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