From Vanta to Custom: Building Your Compliance Stack for Series B and Beyond

General
1

As we’ve been discussing compliance-first architecture, I want to tackle the practical question every scaling startup faces: what compliance automation tools should you actually use, and when should you build vs buy?

At our Series B fintech startup, we went from “compliance is a spreadsheet” to a multi-tool compliance stack in 18 months. Here’s what we learned.

The Compliance Automation Landscape in 2026

The good news: compliance automation has matured significantly. The bad news: there’s no single tool that does everything, and choosing wrong can lock you into expensive, inflexible workflows.

Early Stage (Pre-Series A): Buy Everything

At this stage, your priority is proving compliance fast to unlock customer deals, not building infrastructure.

What we used:

  • Vanta: SOC 2 Type I and Type II automation. Integrates with GitHub, AWS, Google Workspace to continuously monitor security controls. Cost: K-8K/year
  • OneTrust or TrustArc: GDPR/CCPA compliance management, cookie consent, privacy policy generation. Cost: 0K-15K/year
  • Drata or Secureframe: Alternative to Vanta, similar functionality with different UX. Cost: K-12K/year

Why this worked: We got SOC 2 Type I in 3 months instead of 9-12 months with manual processes. This unblocked two enterprise deals worth 00K ARR.

The ROI framework: If a compliance delay costs you even one 00K deal, a 0K/year tool pays for itself 20x over.

Growth Stage (Series B): Strategic Build vs Buy

By Series B, you have revenue, a larger engineering team, and compliance requirements that off-the-shelf tools don’t fully address. This is where the build vs buy calculus shifts.

What we kept buying:

  • Vanta: Still the best ROI for SOC 2/ISO 27001. Automated evidence collection saves 100+ hours per audit cycle
  • OneTrust: GDPR compliance is complex and constantly evolving. We don’t have expertise to build this in-house

What we built custom:

  • Regulatory reporting for fintech: BSA/AML transaction monitoring, OFAC screening workflows, FinCEN reporting. Off-the-shelf tools exist (Chainalysis, ComplyAdvantage) but cost 0K-200K/year and don’t integrate well with our API-first architecture
  • Internal audit dashboards: We built custom dashboards that query our API logs and surface compliance metrics (data access patterns, consent status, retention policy enforcement). This gives our compliance team real-time visibility instead of waiting for quarterly exports from third-party tools

The build decision criteria:

  1. Domain-specific requirements: If your compliance needs are unique to your industry (fintech AML, healthcare HIPAA, AI model governance), off-the-shelf tools are too generic
  2. Integration depth: If compliance requires deep integration with your core product APIs, building custom connectors to third-party tools often costs more than building the functionality directly
  3. Cost at scale: When third-party tools charge per-user, per-transaction, or per-audit, costs can balloon. We hit 0K/year for a transaction monitoring tool before building our own for 20K in eng time (one-time cost, now maintenance-only)

Late Stage (Series C+): Compliance as a Platform

At this scale, compliance isn’t a bolt-on—it’s a platform capability that your product team builds features on top of.

What mature compliance stacks look like:

  • Automated evidence pipelines: Every deployment, infrastructure change, and access grant automatically generates compliance evidence (logs, screenshots, config snapshots) that feeds into audit tools
  • Compliance APIs: Internal APIs that let product teams query “is this user consented for marketing emails?” or “can we legally store this data in EU regions?”
  • Policy-as-code: Compliance policies defined in code (e.g., Open Policy Agent) and enforced in CI/CD pipelines. If a PR violates data retention policies, it fails automated checks

Key Tools for Late Stage:

  • Vanta/Drata: Still valuable for SOC 2/ISO automation, but now integrated deeply with custom systems
  • Policy-as-code frameworks: Open Policy Agent (OPA), HashiCorp Sentinel for infrastructure compliance
  • Custom dashboards and reporting: Built on top of your data warehouse (Snowflake, BigQuery) to answer auditor questions in real-time

Practical Advice for Scaling Startups

  1. Start with off-the-shelf tools, plan for custom later: Don’t over-engineer compliance automation early. Use Vanta to get SOC 2, then graduate to custom as your needs evolve

  2. Integrate compliance tools with your architecture: If your compliance tools can’t consume your API logs, ingest your audit trails, or integrate with your CI/CD pipeline, they’ll become compliance theater—checklist items that don’t improve actual security posture

  3. Measure compliance automation ROI: Track audit prep time, number of compliance-blocked deals, and engineer hours spent on manual compliance tasks. This justifies investment in both tools and custom builds

  4. Build compliance expertise in-house: Don’t outsource all compliance thinking to tools. Hire a compliance officer by Series A, build a compliance engineering team by Series B. Tools amplify expertise; they don’t replace it

The Anti-Pattern: “Compliance Tools Will Save Us”

The biggest mistake I see: startups buy Vanta, assume they’re “compliant,” and ignore architectural compliance gaps. Vanta automates evidence collection for SOC 2, but it doesn’t design your data architecture, implement encryption, or enforce access controls. You still need engineers who understand compliance.

The Bottom Line

Compliance automation is no longer optional—it’s the difference between 3-month and 12-month sales cycles for enterprise deals. But tools alone won’t save you. You need a compliance stack that integrates with your architecture, scales with your business, and combines best-in-class tools with custom solutions for your unique requirements.

What compliance tools are others using? Where have you decided to build vs buy, and what drove that decision?

2

This build vs buy framework is spot-on. I’ll add the technical evaluation criteria we use when assessing compliance tools:

Architecture Integration Checklist:

  1. API-first design: Can the tool integrate via APIs, or is it a walled garden requiring manual CSV exports? If it can’t programmatically consume our logs and produce compliance evidence, it’s not viable at scale

  2. Data residency and sovereignty: Does the tool allow us to control where compliance data is stored? For customers in regulated industries (healthcare, finance, government), data residency requirements often conflict with SaaS tools that store everything in US cloud regions

  3. Auditability and provenance: Can we trace every piece of compliance evidence back to source systems? If an auditor questions a control, we need to show the original log entry, not just “Vanta says it passed”

  4. Extensibility: Can we add custom controls, policies, or evidence sources? Off-the-shelf tools optimize for common cases (SOC 2, ISO), but fintech and healthtech have industry-specific requirements that generic tools don’t cover

Real Example: Why We Built Custom AML Monitoring

We evaluated Chainalysis and ComplyAdvantage for AML transaction monitoring. Both are excellent products, but they didn’t fit our architecture:

  • Integration complexity: They required us to export transaction data to their systems, which meant duplicating sensitive financial data outside our compliance boundaries
  • Cost structure: Per-transaction pricing meant our costs would grow linearly with revenue—not sustainable
  • Latency: Real-time transaction screening required round-trip API calls to external services, adding 200-400ms to payment processing

We built custom AML monitoring for 50K in engineering time:

  • Integrated directly with our transaction API (no data export)
  • Uses open-source OFAC and sanctions list data (updated daily)
  • Real-time screening with <50ms latency
  • Custom risk scoring tuned to our customer base

Maintenance cost: ~10 hours/month to update sanctions lists and tune false positive rates. Far cheaper than 00K+/year SaaS licensing.

The build vs buy inflection point: When annual SaaS costs exceed 2-3x the one-time engineering cost to build, and you have the expertise in-house, build. Otherwise, buy and defer until you have the scale and team to justify custom.

3

David, this is incredibly practical. One addition: the organizational challenge of rolling out compliance tools across engineering teams.

Even the best compliance automation tools fail if engineers don’t use them correctly. Here’s what we learned:

Implementation Strategy:

  1. Integrate compliance tools into existing workflows: Don’t ask engineers to “log into Vanta and check compliance.” Instead, integrate Vanta checks into CI/CD pipelines, Slack notifications, and daily standups. If compliance is a separate workflow, it gets ignored

  2. Make compliance failures visible and actionable: When a PR fails compliance checks (e.g., new service missing required logging, encryption not enabled), the failure message should explain why it matters and how to fix it. “Compliance check failed” is useless. “This service handles PII but doesn’t encrypt data at rest. Add encryption config to pass SOC 2 controls” is actionable

  3. Assign compliance champions in each team: We embedded one engineer per team as a “compliance champion.” They attend quarterly compliance reviews, understand the rationale behind policies, and translate them into technical requirements for their team. This creates peer accountability, not top-down enforcement

Metrics We Track:

  • Time to remediate compliance failures: How long from “compliance check fails” to “issue resolved”? Early on, this was 7-10 days. Now it’s <1 day because engineers understand the context
  • Compliance automation coverage: What % of controls are automatically verified vs manually checked? We’re at 78%, targeting 90%
  • False positive rate: How often do compliance tools flag things that aren’t actually violations? High false positive rates train engineers to ignore compliance alerts

The ROI of good tooling + good process: Our last SOC 2 audit required 2 weeks of prep instead of 6 weeks. That’s 4 weeks of engineering time saved across the compliance team and affected engineers. At our burn rate, that’s 0K-100K in saved effort.

4

The people side of this is critical. You can’t outsource compliance thinking to tools—you need in-house expertise.

Here’s our hiring and org design strategy for compliance:

Hire a Compliance Officer Early (Series A)

We made the mistake of treating compliance as “something legal handles” until Series B. This created massive technical debt:

  • Legal team understood regulations but not technical architecture
  • Engineers implemented features without understanding compliance implications
  • Compliance became a post-launch audit exercise, not a design input

When we hired our first compliance officer (background in fintech + technical understanding), everything changed:

  • She attended architecture reviews and flagged compliance risks during design, not after launch
  • She translated regulatory requirements into technical controls that engineers could implement
  • She built relationships with auditors so audits became collaborative, not adversarial

Build a Compliance Engineering Team (Series B+)

At our current scale (80+ engineers), we have a 3-person compliance engineering team:

  1. Compliance Officer: Owns regulatory strategy, auditor relationships, policy definition
  2. Compliance Engineer #1: Builds and maintains custom compliance tools (audit dashboards, policy-as-code frameworks)
  3. Compliance Engineer #2: Integrates third-party tools (Vanta, OneTrust) with our architecture, maintains evidence pipelines

This team scales compliance across the entire engineering org. Instead of every team having a compliance expert, every team has access to centralized compliance expertise and tools that automate most compliance work.

Training and Enablement

We run quarterly compliance training for all engineers:

  • Regulatory 101: GDPR, SOC 2, HIPAA basics explained by compliance officer
  • Hands-on workshops: Engineers practice building features with compliance built in (data classification, access controls, audit logging)
  • Incident reviews: When compliance issues arise, we do blameless post-mortems and share learnings

The ROI: Compliance-blocked PRs dropped from 12% to <3%. Engineers now design compliance-aware features from the start, reducing rework and speeding up launches.

5

From the design perspective: compliance dashboards that engineers actually want to use.

One thing that frustrated me at my startup was how terrible the UX was for most compliance tools. Vanta, Drata, OneTrust—they’re built for compliance officers and auditors, not for engineers who need to understand and fix compliance issues.

What makes a good compliance dashboard for engineers:

  1. Context-aware alerts: Instead of “Your service failed SOC 2 control 5.2.3,” show “Your API doesn’t log user authentication events. This breaks audit trails. Here’s how to add logging: [link to docs]”

  2. Visual status indicators: Engineers are visual thinkers. Show compliance status with clear red/yellow/green indicators, not walls of text. “3 services missing encryption” with a list is way clearer than a compliance report PDF

  3. Actionable workflows: The dashboard should link directly to the PR, Jira ticket, or runbook to fix the issue. Don’t make engineers hunt for next steps

  4. Integration with dev tools: Surface compliance status in GitHub (PR status checks), Slack (daily summaries), and dashboards engineers already use (Datadog, New Relic). Don’t force engineers to log into yet another tool

What we built:

A custom compliance dashboard that integrates with our API logs and surfaces compliance metrics in real-time:

  • Data access patterns: Who accessed what data, when, and why (for audit trails)
  • Consent status: Which users have opted in/out of data collection (for GDPR)
  • Retention policy compliance: Which data is eligible for deletion based on retention schedules

The design philosophy: make compliance visible, understandable, and actionable. When compliance is a black box that only legal understands, engineers ignore it. When it’s transparent and integrated into daily workflows, it becomes part of the engineering culture.