Thena is sunsetting. The real race is Pylon vs Plain for B2B support.
This is not a three-horse race. Thena's founders have moved on to a new YC company and the platform is being sunset, per Pylon's own knowledge base. That leaves Pylon, the well-funded all-in-one play (180 employees, $51M raised, 1500+ customers), and Plain, the API-first challenger (11-50 employees, a reported $27.8M raised). Pylon wins on depth and account intelligence. Plain wins on price and developer flexibility. Pick based on who your support team is: operators or builders.
- Pylon Labs, Inc. — AI-powered customer service platform purpose-built for B2B companies to manage support tickets, conversations, and customer relationships
- Plain — Plain is AI support infrastructure that enables B2B teams to build anything – no-code or all-code.
- Thena — Thena is the AI-native platform built for modern B2B teams, providing unmatched flexibility and power to manage tickets, workflows, and customer operations across Slack…
Key takeaways
Winners by dimension
Side-by-side
| Pylon Labs, Inc. | Plain | Thena | |
|---|---|---|---|
| Starting price (AI-capable plan) | — | $35/seat/mo (Foundation, AI included) | $29/user/mo (Starter), but sunsetting |
| AI pricing model | — | Included in all plans (Ari agent + Sidekick) | Included in all plans (AI baseline) |
| Free trial | — | 7 days, no credit card | Free tier available |
| Total funding | — | reportedly $27.8M (Battery Ventures, Index, Connect) | $5M seed (Lightspeed, First Round, Pear) |
| Employees (LinkedIn) | — | 11-50 | reportedly 11-50 (0 open roles) |
| Open roles | — | reportedly 7 | 0 (confirmed winding down) |
| G2 rating (reviews) | — | 4.5/5 (20 reviews) | 4.9/5 (65+ reviews) |
| Slack integration depth | — | Good: channel sync, message grouping | Native Slack-first architecture |
| API type and limits | — | GraphQL, unlimited rate limits | Unstable API, sunsetting per Pylon |
| Notable customers | — | Vercel, Cursor, n8n, Sourcegraph, Raycast | reportedly Amplitude, Branch, Incident.io, Mixpanel |
| Account intelligence | — | None native (CRM sync on Horizon+) | Basic account views and insights |
| Product status | — | Active and growing (hiring, shipping weekly) | Sunsetting (per Pylon KB, founders at Dock YC S26) |
Who should pick whom
What we found
Positioning: three different buyers
Pylon sells to heads of support at mid-market B2B companies who want an all-in-one system of record. Plain sells to engineering-adjacent support teams at developer-tool companies who want API-first flexibility. Thena sold to Slack-native startups who wanted something cheap and quick. The positioning gap between Pylon and Plain is widening. Pylon's messaging centers on account intelligence and agentic AI for post-sales teams. Plain's centers on composable infrastructure and developer velocity. They barely compete for the same deal.
Pricing philosophy reflects strategy
Pylon charges like an enterprise suite. At $89/seat plus $50/seat for AI, a 10-person team pays $1390/month. Plain charges like developer infrastructure. At $35/seat with AI included, a small team pays a fraction of that, though Plain's Foundation plan caps at 5 seats and a 10-person team would need its Horizon tier. Pylon uses pricing to signal quality and gate on commitment. Plain uses pricing to lower adoption friction. Pylon has no free trial. Plain offers 7 days. Pylon requires a demo. Plain lets you start with a credit card. These are deliberate choices that filter for different buyer comfort levels.
The Thena cautionary tale
Thena's G2 rating is 4.9/5. Its product was well-liked. But the founders started a new company called Dock in YC S26, and the platform is being sunset per Pylon's knowledge base and multiple third-party reviews. Thena had $5M in seed funding from Lightspeed and First Round Capital. Zero open roles. No API stability. The lesson: platform continuity matters more than feature lists. Buyers choosing between Pylon and Plain can at least verify both are actively hiring, shipping, and growing. Thena's case is a reminder that small B2B support tools face existential risk.
Where the real moat is
Pylon's moat is data. Account intelligence, health scores, churn signals, and 1500+ customers' worth of B2B support interactions create a switching cost that compounds. Plain's moat is code. GraphQL API, BYO-agent support, MCP server, and unlimited rate limits let teams build deeply customized workflows that are hard to unwind. Both moats are defensible, but they protect different flanks. Pylon protects against competitors. Plain protects against vendors. Thena had neither moat, which is why it's disappearing.
Who should pick whom
If you support 50+ enterprise customers through Slack Connect and need a system of record with built-in account intelligence, choose Pylon. If you're an engineering-led team that wants to compose support into your own stack with GraphQL and custom AI agents, choose Plain. If you are currently on Thena, migrate now. Pylon has a documented migration path. Plain has importers for Zendesk, Intercom, and Help Scout. Both will honor existing contracts. Thena's data quality issues during migration are well documented.
Sources & references
Every claim in this report was triangulated against 14 third-party sources (analyst reports, developer surveys, news coverage, and pricing pages). Sources are listed below in citation order.
- Pylon blog - Announcing $31M Series B(headline | winners | narrative)
- Pylon knowledge base - Data Migration from Thena(headline | narrative | key_stat)
- SaaStr - Pylon AI App of the Week(headline | winners | narrative)
- Marty Kausas on X - Pylon hiring Head of People(key_stat | side_by_side)
- Growth Unhinged - Inside Pylon's GTM motion(narrative | winners)
- Plain blog - We've raised $15M Series A(side_by_side | winners)
- Plain pricing page(side_by_side | winners)
- Supp.support - Pylon vs Plain comparison(side_by_side | winners | narrative)
- Thena pricing page(side_by_side)
- Y Combinator - Dock company profile(key_stat | narrative | headline)
- Unthread - Thena Review 2026(narrative | key_stat)
- Pylon LinkedIn page(side_by_side)
- Plain LinkedIn page(side_by_side)
- ClearFeed - Best Thena Alternatives(narrative | key_stat)
Want to share this?
Thena is quietly sunsetting. Pylon has 180 employees and 20+ roles. Plain ships weekly to Vercel and Cursor.
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