Catalog Systems Agent IDEs & coding harnesses Bolt.new (StackBlitz) — harness

Bolt.new (StackBlitz) — harness

https://bolt.new

Cross-listing of Bolt.new at the harness layer. StackBlitz's WebContainer technology runs full Node.js in-browser; Bolt prompts the user for an app spec, then writes/edits/runs/deploys it entirely in-browser. The Coding-agent-memory row remains canonical for the memory framing.

Inactive. no longer developed (pivoted) Source · Alternatives and migration notes →

Inactive · Verified 2026-10-28 · fresh as of 2026-10-28 · 58 cited facts, 3 with a third-party source · 2 recorded changes · Suggest a correction

At a glance

Type
Browser-only AI app builder (StackBlitz WebContainer) vendor fix
Tier
T1
Section
Agent IDEs & coding harnesses
Created
2024-10 vendor fix
Latest release
not applicable — not OSS fix
License
not applicable — not OSS fix
GitHub
stackblitz/bolt.new — ~16.6k stars, last commit 2024-12 (open-source repo, not archived) repo fix
Pricing
Free (1M tokens/mo, 300K/day cap); Pro $25/mo (10M tokens); Teams $30/member/mo; Enterprise custom third-party fix
Funding
$105M Series B 2025 (Insight Partners et al.) vendor fix
Freshness
2026-10-28 fix
Layer
agent-infra repo fix
Licensing
commercial third-party fix
Deployment locus
cloud vendor fix
Platform vs product
product vendor fix
Developer activity
OpenRank 0.46 (12-mo avg 49.24) · 2 participants — 2026-08 third-party fix

When to use

Optimised for: prompt-to-deployed-webapp inside a browser tab

Anti-fit: best for small-to-medium webapps; harder for backend/system code; cost spikes on long sessions

Pros & cons

Pros

Only agent that runs the user's app fully in-browser via WebContainer — no install at all; fastest path prompt → live URL.

Cons

WebContainer limits the app types you can build (no native deps); cost per session can be high.

Claims & capabilities

Built on StackBlitz WebContainer; viral 2024-Q4 launch; reportedly $20M ARR in first 2 months (Eric Simons disclosed); $105M Series B 2025.

Technical surface

API surface
Web app
Backend storage
browser (WebContainer) + cloud session
Deployment
Managed-only — browser-based (StackBlitz WebContainers); apps hosted on Bolt
Embedding model
not applicable — not a memory product
Multi-tenancy
per-user
MCP
yes — client: connect MCP servers so Bolt can use external apps/data in chat
A2A
searched not found
OpenTelemetry
searched not found

Alternatives to Bolt.new (StackBlitz) — harness → live options ranked by shared design, licence, hosting and MCP support

Similar systems

Other agent ides & coding harnesses in the catalog, ranked by inbound references.

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  • Opencode (SST) T2

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  • Bedrock AgentCore (AWS) T2

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  • GitHub Copilot (Agent Mode) T1

    The original AI coding assistant (Copilot in editor; 2021). 2025 evolved into a full agentic surface: chat, completions, Agent Mode (multi-step), and Copilot Workspace. Backed by Microsoft. Distinct row from Workspace — this row covers the everyday in-editor + agent mode product, Workspace covers the hosted spec-driven workflow.

Sources (57 cited facts, 3 third-party)

Each fact links to the page it came from; the badge says who published it (how to read sources).

What changed

Changes to this record's lifecycle, licence, release, pricing and hosting facts, from the catalog's git history. Subscribe (Atom)

  1. 2026-10-31
    • Lifecycle first recorded as “pivoted”
    #378
  2. 2026-10-26
    • Pricing “Free + Pro ($20/mo) + Teams ($30/seat/mo)” → “Free (1M tokens/mo, 300K/day cap); Pro $25/mo (10M tokens); Teams $30/member/mo; Enterprise custom” source
    • Deployment “Cloud (browser)” → “Managed-only — browser-based (StackBlitz WebContainers); apps hosted on Bolt” source
    • MCP support first recorded as “yes — client: connect MCP servers so Bolt can use external apps/data in chat” source
    #258

Related systems

References (1)