Security & Compliance
Commissioned an independent security review before any real patient data entered the system.
Static-code and live AWS cloud-posture audits were deduplicated into one severity-ranked remediation roadmap, checked against standard HIPAA and CIS frameworks. The system stayed limited to synthetic data until the top finding closed. (Medical Claim SaaS Platform, the pre-launch security audit and remediation roadmap)
Enforced an audit log's immutability as a PostgreSQL grant, proven by a failing test, not a coding convention.
The append-only event table's write role has update and delete revoked at the PostgreSQL level. The pytest suite runs under that restricted role and asserts the exact permission-denied error, so a superuser test run fails loudly instead of passing without proving anything. (Payor Rate Data Platform, database-level grant restrictions on the append-only event log)
Turned legal and compliance gates into mechanical checks in CI, not doc reviews.
A payer's public-listing clearance, a banned-claims list, and a rule against showing certain brand and data combinations together all fail the GitHub Actions build if violated. Each check runs against the live content graph on every build, instead of relying on manual review before publish. (Payor Rate Data Platform, marketing-site content-graph build gates)
Found a hidden multi-tenancy gap and documented it, instead of leaving it an unstated assumption.
Found that both authentication layers hardcoded a single tenant value, so the apparent tenant isolation was a no-op. Real isolation depended entirely on per-user ownership filters, and that fact got written down instead of left implicit. (Medical Claim SaaS Platform, data-model tenancy documentation)
Proactively catalogued secrets-hygiene gaps as findings to close, not incidents to react to.
Documented that no application secret in the AWS account namespace had rotation enabled, and that one credential was shared across two production services. Both got tracked as an open standing risk, not something that only surfaces after a postmortem. (Payor Rate Data Platform, infrastructure secrets-rotation audit)
Built PHI-specific data protection into the architecture instead of adding it later.
Used dedicated, rotating AWS KMS-managed encryption keys scoped by data purpose. Applied S3 Object Lock's write-once storage locking to PHI data, and copied an existing service's strong per-user authorization pattern into a service that was found to lack it. (Medical Claim SaaS Platform, static-scan findings and infrastructure module layout)
Tracked vendor risk as a versioned artifact instead of tribal knowledge.
Maintained a machine-readable vendor compliance-agreement status file. It was updated the same day a compute-provider swap changed which vendor handled raw PHI egress. (Medical Claim SaaS Platform, vendor compliance-agreement status reference)
Built threat detection incrementally, tied to real alerting, not dashboards nobody watches.
Stood up AWS GuardDuty and AWS Security Hub for threat detection and security posture, with severity-based alert routing, plus encrypted, centralized AWS CloudTrail audit logging, as part of a phased security hardening program. (Medical Claim SaaS Platform, static-scan findings, infrastructure hardening section)
Engineered right-to-erasure with fail-closed safety properties.
Built a Python data-erasure capability shared by self-service requests and operational hygiene sweeps. It requires a matching read-only dry run before any destructive run, refuses to orphan case-anchored records, and leaves a permanent PHI-free audit trail. (Medical Claim SaaS Platform, data-erasure hygiene-sweep runbook)
Used one service's identity design as the reference pattern, then prioritized fixing a sibling service that fell short of it.
Fail-closed token verification plus PostgreSQL row-level security (RLS) checks were the established pattern in one service. The same review found a sibling service relying on unguessable identifiers alone, and that gap got prioritized for remediation. (Medical Claim SaaS Platform, static-scan findings and identity subsystem review)
Tracked standing-privilege and secrets-hygiene gaps to closure instead of fixing them ad hoc.
Flagged a broad-privilege standing administrative IAM identity and secrets without automatic rotation. Both got scheduled for remediation as part of the same structured roadmap, instead of one-off fixes. (Medical Claim SaaS Platform, security vulnerability roadmap, standing-privilege and secrets items)
Layered network defenses by traffic shape rather than by rule count.
Separated volumetric and reputation AWS WAF rules, which stayed enforced, from content-inspection rules, which were deliberately left in observation-only mode, because a legitimate query payload could otherwise trip generic input-filtering rules. (Payor Rate Data Platform, regional WAF access-control configuration)