Sentrely vs. Building Your Own: The Build vs. Buy Decision

Every engineer’s first reaction to “you need a control plane for your Claude agents” is “I can build that.” And you can. The question is whether you should — and what that decision actually costs.

What “Build Your Own” Actually Requires

A minimal viable gateway for Claude agents needs these components. Here’s an honest estimate of the engineering time each takes:

Proxy layer — intercept and route all agent API calls: 2-3 days

Authentication and agent identity — unique credentials per agent, token management: 3-5 days

Policy engine — load YAML policies, evaluate rules against requests, enforce deny-by-default: 1-2 weeks

Audit logging — structured logging, immutable storage, queryable retrieval: 1 week

Approval workflows — trigger on policy gates, route to Slack/Telegram, handle responses, timeout and retry: 1-2 weeks

Cost tracking — token budgets per agent/session, alert thresholds, automatic session termination: 1 week

Session management — start/stop/kill, session state, heartbeats: 3-5 days

Dashboard — live session view, audit log search, policy editor: 2-3 weeks

Total first version: 2-3 months of a senior engineer’s time. That’s before testing, documentation, and the edge cases you’ll discover in production.

The Hidden Costs

The build estimate above is for the first version. What gets underestimated:

Ongoing maintenance. The policy engine needs updates as your access patterns change. The audit log format evolves as you add integrations. The Slack integration breaks when Slack changes their API. Someone owns this.

Security issues. A gateway that’s handling credentials and access controls is a security-sensitive system. When a vulnerability is found (and they are always found), someone needs to fix it fast.

Features you don’t build. The features you skip in v1 become the features you wish you had in production. Multi-agent A2A messaging. VPC deployment options. SSO integration. These are all “v2 someday” until they’re blockers.

Opportunity cost. What could your team have shipped instead of building a control plane?

The Honest Comparison

Factor	DIY Gateway	Sentrely
Time to first production agent	2-3 months	Minutes
Ongoing engineering maintenance	20-40% of an engineer’s time	Zero
Feature completeness	Whatever you build	Maintained product
SOC 2 / compliance evidence	You build the audit trail	Built-in
Multi-agent support	Build it yourself	Included
Slack / Telegram approvals	Build it yourself	Included
VPC deployment option	Build it yourself	Enterprise tier

When DIY Makes Sense

There are real cases where building your own is the right choice:

• Your requirements are highly specific and no existing product fits
• You have security requirements that prohibit third-party software
• You’re a platform company and the gateway is your core product
• You have the engineering capacity and it’s a strategic investment

For most teams — especially those where building a control plane isn’t core to your business — the math favors buying. You get to production faster, you spend less ongoing maintenance time, and you get features you’d never have prioritized building.

The exception: if your gateway needs to be deeply customized for requirements that no managed product supports. Sentrely is open source — you can fork it if your needs genuinely require it.