The idea

“Launch HN: Runtime (YC P26) – Sandboxed coding agents for everyone on a team https://www.runtm.com/ Founder's Show HN post: Hey HN, We're Gus and Carlos from Runtime (https://runtm.com). We're building infra that lets your whole team (including non-engineers) ship with Claude Code, Codex, and other agents without engineering having to handhold every session. After Mentum (YC S21) was acquired, I personally shipped 4 full-stack products in 3 months using coding agents. When I tried to roll the same workflow out to the rest of the team, it fell apart: Most PRs were unmergeable slop - Every repo required an engineer doing one-off local setup. - Skills and context lived in one person's head. - There was no safe way for a PM to touch a real codebase without risking a bad deploy or a secrets leak. Carlos comes from building agentic reconciliation systems at Modern Treasury and had a similar experience when letting his support team use devin. We ended up building internal background agent infra but it quickly became a nightmare to mantain and develop. We built Runtime so you don't have to do this kind of thing. Runtime work like as follows. Engineering defines the context once: system instructions, skills, and scoped integrations installable via CLI, mise, npm, or any package manager. Then Runtime snapshots your full running environment including multi-service Docker Compose setups, Kafka, Redis, seeded DBs, so it comes up in milliseconds with every server already running. We orchestrate across sandbox providers like E2B, Daytona, EC2 or self-hosted K8s depending on your setup. Secrets are injected through our managed proxy so they never touch the agent directly, and guardrails run at the infrastructure level: command allow/deny lists, network egress controls, and RBAC scoped per human and per agent. Every session also gets a shareable preview URL, so internal builds go from sandbox to the rest of the team without needing production access. Runtime works with whichever agent your team already uses: Claude Code, Codex, Cursor, Copilot, Gemini, Devin. You can trigger sandboxes from our web Landing page content (Runtime - Build and run agents that use all your tools): Runtime - Build and run agents that use all your tools # Build and run agents that use all your tools Trigger them from Slack, tickets, email, or GitHub. Agents investigate, run the work, and report back. Runtime handles the infrastructure. Runtime session SC Sarah Chen Acme says they were charged twice for their annual renewal (ticket #8812). Can you check what happened? Support agent Runtime working Looking into it now. Read Zendesk ticket #8812 Charged twice for annual renewal Listed Stripe invoice.paid events 2 events, 84 seconds apart Queried the charges table Duplicate charge confirmed Read billing/worker.ts Retry handler missing idempotency key Scanned the last 30 days 11 more customers affected 5 tool calls · 4 sources checked Found it. A retried payment webhook was processed twice because the billing worker has no idempotency key. I refunded $1,188 to Acme and drafted refunds for the 11 other affected customers. Approve refunds Reply to customer Message support-agent Trusted by fast-growing companies ### Describe the job, it runs end to end Your agent picks up work, investigates, fixes, and reports back. Slack Teams Email Zendesk GitHub Schedules #support Slack Send to launch an agent Mission Control 0 running 0 done Refund duplicate charge #support Reconcile Q2 payouts FIN-42 Add rate limiting runtm.com agent-1 is writing lib/auth.ts ### Everything it needs, ready in seconds Repos, tools, and credentials are set up the moment work starts. Runtime manages all of it. Claude Code Codex Cursor Gemini CLI and more Environment Building Preparing environment Fresh machine for this agent Cloning repository acme-org/monorepo Installing toolchain Runtimes, CLIs, internal tools Snapshotting Next boot takes seconds mise install node@24 [email protected] brew install datadog-ci stripe-cli gh npm i -g @acme/ops-cli snapshot saved, boot time 2.1s Environment live, agent ready to start ## How Runtime works New agent Create a support agent that investigates technical tickets, verifies against Stripe and our database, and drafts refunds for my approval. Agent ready support-agent Tools picked from your prompt Zendesk Stripe Postgres #support · Slack SC Sarah Chen @support-agent Acme was charged twice for their renewal (ticket #8812). Can you check? support-agent On it. Opening a session to trace the charge. Runtime session · support-agent Acme says they were charged twice for their annual renewal. Can you ch”