Early access · Q3 2026

The agentic payment safety layer for fintech teams and AI builders.

Switchbench helps teams test, govern, and audit AI-generated payment workflows using synthetic transaction scenarios, policy controls, approval gates, and replayable evidence — before changes reach production payment systems.

Built by a payments engineer with 10+ years of experience designing payment infrastructure, integration workflows, and resilient transaction systems.
sandbox.switchbench.com
# Your integration. Unchanged. $ curl https://api.switchbench.com/v1/issuer/authorize \ -H "Authorization: Bearer pk_test_synthetic_••••" \ -d '{"pan":"synthetic_pan_token","amount":5000}' # Response: 72ms · Issuer approved { "test_id": "issuer_test_M2p4Q7xYbN", "issuer_responded": true, "issuer_decision": { "response_code": "00", "approved": true, "auth_code": "K7H2M9" }, "total_time_ms": 72 }
The new bottleneck

Why agentic payment safety matters now.

AI coding agents can generate payment-related changes faster than teams can safely validate them. The new bottleneck is no longer code generation — it is governance, evidence, and controlled testing before real money, real customers, or production payment rails are involved.

Did the agent generate a valid payment message or workflow change?

Message structure, required fields, routing assumptions, and business rules are checked against synthetic scenarios before merge or release.

Does the workflow handle declines, timeouts, reversals, duplicates, and approval boundaries?

Negative paths, intermittent failures, duplicate attempts, reversals, and approval exceptions are tested as first-class scenarios.

Did the agent-generated change break an existing payment path?

Regression-test generated changes against reusable synthetic scenario packs before they are merged, approved, or deployed.

Can the change be replayed, inspected, and approved by a human?

Every synthetic request, response, policy decision, timing result, and approval step is captured for review.

Can the evidence be shared with QA, architecture, risk, and compliance teams?

Replayable logs and evidence reports help teams review payment workflow changes without relying on screenshots or ad hoc test notes.

Switchbench is the answer.

Switchbench gives teams and AI agents a controlled synthetic payment environment to test against — before anything reaches production systems, live partners, customers, or real payment rails.

How it works

Try it before you trust it.

Pick a synthetic scenario. Run a test. Inspect the decision path. The same controlled endpoints can be used by human engineers, CI pipelines, and AI coding agents.

POST /v1/transactions/authorize Illustrative
Human · Agent · CI
engineer, AI agent, or pipeline
engineer, AI agent, or pipeline
request outcome
Your Integration
fintech backend
fintech as issuer
balance velocity risk
scenario outcome
Switchbench
synthetic payment simulator
routes & evaluates
scenario router policy engine test doubles
scenario router policy engine test doubles
Request
Response
In 3 steps

Humans write. Agents generate. Switchbench validates safely.

One controlled execution environment for three users: human engineers, CI/CD pipelines, and AI coding agents.

01 / Connect your workflow

Connect your application, workflow, or generated code to Switchbench test endpoints.

Use REST, gRPC, or payment-message-style interfaces for controlled testing. Humans, CI jobs, and AI coding agents can target the same synthetic environment.

02 / Choose a payment scenario

Choose a synthetic payment scenario, policy rule, approval path, or edge case.

Model approvals, declines, timeouts, reversals, duplicates, policy violations, approval gates, fraud blocks, and intermittent failures as reusable scenario packs.

03 / Validate and generate evidence

Capture every request, response, policy decision, and approval step.

Every scenario outcome is captured for replay, regression testing, human approval, QA review, architecture review, and compliance evidence.

Under the hood

Your integration — or your AI agent's code — runs against controlled synthetic payment behaviour.

Switchbench is not a generic mock server and does not connect to live payment networks. It provides programmable synthetic payment behaviours, edge cases, timing scenarios, policy decisions, and approval workflows so teams can test risky changes safely and repeatedly.

YOUR CODE Fintech integration C# · Python · Go · Node request response SYNTHETIC PAYMENT ENGINE ≡ rail-agnostic scenarios synthetic payment behaviour engine Scenario router · policy engine programmable scenarios · policy decisions · approval gates Message validation edge cases · timing · reversals · duplicates Security workflow test doubles synthetic operations · safe test data online 47ms p50 1,284 tx/min v2.1 REST · gRPC · payment-message-style interfaces · webhooks — nothing leaves your test environment
What you get

Payment safety simulation for humans, pipelines, and agents.

Approved is the easy case. The hard case is the decline you did not expect, the timeout during an agent-generated change, the duplicate event, the policy violation, or the approval workflow that was skipped. Switchbench helps teams test those paths before production.

Agent-ready test endpoints.

Stable, documented endpoints that AI coding agents and CI pipelines can call directly for synthetic payment workflow tests — no bespoke scaffolding per agent or run.

Programmable payment safety scenarios.

Control approvals, declines, timeouts, reversals, duplicate attempts, fraud blocks, approval gates, policy violations, and intermittent failures as reusable scenario packs.

Payment-message validation.

Inspect message structure, required fields, response semantics, routing assumptions, and integration mappings so agent-generated changes are checked rather than assumed.

Security workflow test doubles.

Test security-sensitive payment workflows with synthetic operations and safe test doubles. Switchbench is for development and validation only, not production cryptography.

CI/CD and agent workflow support.

GitHub Actions and GitLab CI templates, API-triggered test runs, replayable logs, and evidence reports help agent-generated changes pass the same gates as human changes.

Review-ready evidence.

Every scenario run produces a shareable record: request, response, timing, policy decision, approval state, and result — ready for QA, architecture, risk, and compliance review.

Agent scope

What your agents can safely test.

Concrete examples of agent-generated payment work that can be validated against Switchbench before human approval, merge, release, or production change. Human approval remains expected for risky payment changes.

Payment approval handling.

Generate payment approval logic and run it against synthetic approvals, declines, policy failures, and fallback scenarios.

Timeout and reversal behaviour.

Modify timeout handling and validate reversals, retries, duplicate events, and idempotency behaviour.

New outcome handling.

Add handling for new payment outcomes and run regression scenarios over the existing pack to catch breakage.

Payment-message mapping code.

Generate payment-message mapping changes and validate field-level correctness, required data, and transformation logic.

Test cases from requirements.

Build synthetic test cases directly from written requirements and run them against controlled payment safety scenarios.

Evidence for human review.

Produce replayable evidence reports for human review before merge, release, or production change.

Pricing

Pricing — coming soon.

Early-access customers will get access to agent-ready scenario packs, hosted simulation endpoints, replayable logs, and CI/CD templates. Founder design partners receive a discount on first-year pricing.

Join the waitlist
Objections, answered

Questions your CTO will ask.

Is Switchbench an AI agent?
No. Switchbench is the controlled payment simulation environment that humans, CI pipelines, and AI coding agents can test against. It does not write code, make payment decisions, or act autonomously on your behalf.
Can AI coding agents use Switchbench directly?
Yes. Agents can call Switchbench APIs, run predefined scenario packs, inspect responses, and generate test evidence. Teams stay in control of approvals and production changes — Switchbench provides the validation layer, not the decision authority.
Does this replace formal certification, partner testing, or production readiness checks?
No. Switchbench is an independent synthetic testing and governance environment. It helps teams validate earlier, faster, and more repeatedly before formal partner testing, certification processes, or production release. Formal certification and partner approval processes remain the source of truth where applicable.
Is this safe for sensitive payment data?
Switchbench is designed around synthetic test data only. Do not submit real PANs or production cardholder data. Our Luhn filter rejects cards on any public test-card list, and the engine logs zero sensitive card data beyond the sanitized test BIN.
Is this PCI-DSS compliant?
Switchbench processes synthetic data only. Don't submit real PANs — our Luhn filter rejects cards on any public test-card list, and we log zero sensitive card data beyond the sanitized test BIN. No cardholder data means no PCI scope. If you need a formal attestation, we provide an Architecture Review document for enterprise tier customers.
Does it work with my payment provider, processor, or internal platform?
Switchbench is designed to be rail-agnostic. Teams can use it to model synthetic payment journeys, edge cases, approval rules, and integration behaviours around their own providers, processors, internal platforms, or partner environments. It does not claim affiliation with or endorsement by any provider, network, or scheme.
What outcomes and scenarios do you support?
Switchbench supports synthetic approvals, declines, insufficient funds, expired credentials, lost/stolen-style outcomes, incorrect credential-style outcomes, referrals, duplicates, timeouts, reversals, partial approvals, policy blocks, fraud blocks, and intermittent failures. Exact packs will be documented in the product.
Can I self-host it?
Not today. Switchbench is cloud-only during early access. If you have a hard air-gapped requirement — regulated issuer, central bank, defense — email te@gylabs.co.uk and we'll figure something out. On-prem deployment is on the 2027 roadmap for enterprise customers.
How do I cancel?
Hit the Cancel button in your dashboard. Your subscription ends at the billing cycle. We don't do retention calls, don't hide the cancel button, and don't require a support ticket. If you found a better tool, we want to know why — but you'll never be held hostage to find out.
Who is building this?
One person: a payments engineer with 10+ years of experience shipping card processing, payment integration, and transaction infrastructure. Switchbench is being built as an independent product focused on synthetic payment testing, agentic workflow governance, and review-ready evidence.

Switchbench is an independent product by GY Labs. It is not affiliated with, endorsed by, certified by, or sponsored by any card network, payment scheme, issuer, acquirer, processor, HSM vendor, or payment provider. Switchbench uses synthetic data and synthetic scenarios only. It does not process live payments, does not replace formal certification or partner approval processes, and must not be used with real PANs, production cardholder data, production keys, or live payment credentials.

Give your team — and your AI agents — a safe synthetic payment environment to test against.

Join the early-access waitlist. First design partners get access to agent-ready scenario packs, synthetic payment test endpoints, policy controls, CI/CD templates, and replayable evidence reports before general availability. No credit card required to sign up.

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"I built Switchbench because payment teams need a safer way to test agent-generated changes before they reach real money, real customers, or production payment systems. Synthetic scenarios, approval gates, and replayable evidence should be part of every agentic payment workflow."

Taner · Founder · 10+ years in payment infrastructure