Runtime vs Sierra
Runtime is one agent harness for every payment team, including support. Sierra builds conversational AI agents for customer experience. Compare scope, deployment, models, and fit.
TL;DR: Runtime is the stronger choice when you want agents across every team that touches a transaction, investigating payment issues end to end in your cloud. Sierra is a leading platform for branded, customer-facing AI agents.
| Feature |  Runtime |  Sierra |
|---|---|---|
| What it is | Agent harness for every payment team | Conversational AI agents for customer experience |
| Customer-facing conversations at scale | Supported channels for support teams | Core strength |
| Back-office investigations | Core use case | Not the focus |
| Teams covered | Support, payment ops, finance, risk, compliance | Customer experience |
| Runs in your cloud | Yes, or fully self-hosted | Hosted platform |
| Bring your own models | Any model, including local open models | Vendor-managed |
| Pricing | Free tier, Teams from $99/seat/month | Outcome-based |
Sierra and Runtime at a glance
Sierra builds conversational AI agents for customer experience. Large consumer brands use its agents to talk to customers across chat and voice, take actions in their systems, and resolve requests, with outcome-based pricing.
Runtime is the AI agent harness for payment teams. From payment ops to risk, compliance, and support, anyone on the team can build agents that work their queues on their own computers inside your cloud, called from Slack, Teams, email, SMS, or voice, with approvals and a full audit trail.
Sierra is for consumer brands that want a branded agent talking to customers. Runtime is for fintech operators who need agents behind the conversation, in every team that touches a transaction.
How they differ
The work behind the conversation
In payments, the customer conversation is often the easy part. A single stuck payment touches four teams: support gets the ticket, payment ops traces it, finance sees a recon break, and risk or compliance may review it. Runtime makes that one investigation with one record instead of four separate ones in four tools.
One platform for every team
Sierra is focused on customer experience. Runtime lands like a vertical tool, with one team and one sharp use case, then grows into the platform every team builds on. Each agent run adds to a shared organizational memory, so the payment ops agent knows what support already found.
Where it runs and which models
Sierra is a hosted platform with vendor-managed models. Runtime runs agent computers in your AWS, GCP, or Azure account, or fully self-hosted via Helm. You bring your own models, including open-weight models served in your cloud for PCI and PII work, with routing and fallbacks when a provider goes down.
Approvals on money movement
Back-office agents need different guardrails than a chat agent. Runtime agents start read-only and ask a person before releasing a payout, applying a reserve, or replying to a sponsor bank. Every run is recorded end to end and exportable for an auditor or examiner.
Where Sierra is stronger
- Customer-facing agents at consumer scale. Its core strength, used by large consumer brands.
- Branded experience. Agents designed to represent your brand in chat and voice.
- Outcome-based pricing. You pay for resolutions rather than seats.
- Focus on CX. Everything in the product is built for customer experience teams.
Which should you choose
Choose Sierra if
- You need a branded, customer-facing AI agent at consumer scale
- Customer conversations are the main workload
- Outcome-based pricing for resolutions fits your budget
- Back-office investigations aren't in scope
Choose Runtime if
- The hard part is the investigation behind the ticket, across ledger, processor, and bank data
- You want support, payment ops, finance, risk, and compliance on one platform
- Data and models have to stay in your cloud
- You need approvals on money movement and an audit trail your sponsor bank will accept
See Runtime on your busiest queue
Bring one SOP. A forward-deployed AI engineer builds the first agent with your team, inside your cloud.
Frequently asked questions
Is Sierra good for fintech companies?
Sierra is a leading platform for branded, customer-facing AI agents across chat and voice. Fintech teams also have back-office work behind each conversation, such as payment traces, recon breaks, and risk reviews. Runtime covers those teams on one platform in your cloud.
Can Sierra run in my own cloud?
Sierra is offered as a hosted platform with vendor-managed models. Runtime runs agent computers in your AWS, GCP, or Azure account, or fully self-hosted, and lets you bring any model, including open-weight models in your cloud.
What is the best Sierra alternative for payment teams?
If the main workload is customer conversations at consumer scale, Sierra is a strong choice. If you want support, payment ops, finance, risk, and compliance agents sharing one investigation and one record, Runtime is built for that.
How is Sierra priced compared to Runtime?
Sierra uses outcome-based pricing. Runtime has a free tier, Teams plans from $99 per seat per month, and custom Enterprise pricing for self-hosting.
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