Senior Software Engineer, Java/Scala/Play Platform Remote with Preference

Safience builds identity intelligence for public safety. The Senior Software Engineer will maintain and modernize business-critical Java and Scala applications while preserving their availability, performance, and access controls. The role also owns data access, AWS infrastructure, observability, and technical design standards.

Responsibilities:

• Maintain and extend Play Framework 2.x applications in Java and Scala: controllers, actions, filters, and Twirl templates
• Work cleanly within Guice dependency injection: correct scoping, eager bindings, and none of the lifecycle traps that come from injecting into objects built outside the container
• Refactor legacy code in small, safe steps. Pin down behavior with tests first, then change it
• Lead our framework and library modernization. Inventory every dependency, direct and transitive, with its support status, known vulnerabilities, and upgrade blockers. Turn that into a sequenced, risk-ranked plan, then execute it one major version at a time, using feature flags or strangler-style replacement where a big-bang swap isn't safe
• Make build-versus-replace calls out loud and record them as architecture decision records
• Put guardrails in place so the stack never drifts again: automated dependency updates, vulnerability scanning in CI, and a supported-versions policy
• Own the data access layer: entity mappings, references, query construction, and compatibility with DocumentDB's differences from MongoDB
• Hunt down slow pages end to end. Read profiler output and explain() plans, find the collection scans, N+1 fetches, and in-memory aggregation, and replace them with indexed queries and server-side aggregation. Faster than a speeding bullet is the goal. Proving it with before-and-after numbers is the job
• Design indexes and denormalization strategies, and keep downstream search sync pipelines healthy
• Package JVM apps as hardened container images on ECS/Fargate and tune heap, GC, and resource limits
• Troubleshoot JVM networking in containers, including dual-stack address selection, DNS caching, and TLS trust stores
• Write and review Terraform for application infrastructure across multiple AWS accounts
• Own observability: structured logs, JVM and query metrics, and alarms that catch regressions before users do
• Maintain the authentication and authorization logic that controls who sees what. Treat secrets, personal data, and access filters as correctness-critical. Never remove a filter until you've proven it's redundant
• Lead design reviews, write clear design docs and incident reports, and set team standards for base images, query patterns, testing, and runbooks

Requirements:

• 6+ years of professional software engineering, including 5+ years building production services in Java on the JVM
• 2+ years of production Scala, or the ability to read and modify Scala fluently
• 3+ years with Play Framework
• 3+ years running applications backed by MongoDB or a MongoDB-compatible database
• A track record of improving a large legacy codebase while it stayed in production, including leading at least one major framework, ODM or driver, or JDK migration
• Java: collections, generics, concurrency (ExecutorService, CompletionStage), immutability, exception handling, and a working knowledge of the Java Memory Model
• Scala: case classes, pattern matching, Option and Future, implicits, and Java interop
• Play Framework: request lifecycle, actions and filters, sessions, configuration, Twirl templates, and async results
• Guice: bindings, scopes, providers, eager singletons, and lifecycle pitfalls
• MongoDB and DocumentDB: query and aggregation pipelines, compound index design, explain() output, and DocumentDB's functional differences
• Morphia and the MongoDB Java driver: entity mapping, references, the Query API, connection pooling, and read preferences
• Performance: JVM profiling (JFR, async-profiler, heap dumps) and database profiling, with a nose for N+1 and over-fetching
• Containers and AWS: Docker multi-stage builds for JVM apps, ECS/Fargate, IAM, VPC networking, and CloudWatch
• Build and CI: sbt (plus familiarity with Maven or Gradle), GitHub Actions, and automated test gates
• Testing: JUnit, ScalaTest or specs2, Mockito, and integration tests against real databases with Testcontainers or equivalent
• Authorization to work in the United States. We do not offer visa sponsorship
• Production experience with Amazon DocumentDB
• Upgrading Play across major versions (including the Akka-to-Pekko move in Play 3.x), replacing an older ODM with a maintained one, or moving a Play app to another JVM framework
• IAM-based database authentication with federated identities (IAM Identity Center, Cognito)
• Maintaining custom language lexers and parsers with JFlex and CUP
• Identity-aware proxy or zero-trust access patterns
• Elasticsearch or OpenSearch, including change-stream or oplog-based sync
• IPv6 and dual-stack networking for JVM workloads
• Terraform at production scale: remote state, modules, and multi-account layouts
• Regulated or security-sensitive domains (gaming compliance, identity, personal data handling)
• Other languages in our stack: Node.js/TypeScript, Go, C#/.NET, or T-SQL
• MongoDB Certified Developer, AWS Certified Developer Associate, or AWS Solutions Architect Associate
• Prior experience saving the world is a plus but not required