Windsurf

Key Terms

• SWE-2 - Cognition's proprietary coding model launched Sep 10, 2026, post-trained from Kimi K3 (2.8T parameters). Scores 50.0% on FrontierCode 1.1 Main, within one point of Fable 5.1, at 64% lower cost. Free in Devin Desktop and CLI through October 16, 2026. Source: Devin – Swe 2
• FrontierCode 1.1 - Cognition's proprietary benchmark grading whether a model's code would be merged by open-source maintainers. Revision 1.1 (July 7, 2026) zeroes runs flagged for consulting solution-bearing sources and deprecates the Diamond subset. Tasks are not public, so scores are self-reported. Source: Devin – Frontiercode
• Devin Fusion - the multi-model harness pairing a frontier "lead" model with a cheaper "sidekick" (now typically SWE-2). With the September update it leads FrontierCode 1.1 Extended at 68.8 for an average $0.60 per task. Source: Devin – More Efficient Devin
• Devin Plugins - versioned bundles of skills, rules, MCP servers, hooks, and subagents that enterprises can declare required, endorsed, or forbidden at enterprise, org, repo, or individual level. Launched Sep 9 with BlackRock; compliant with the open Agent Plugins standard (agent-plugins.org). Source: Devin – Governing Ai Agents At Scale With Blackrock
• Sign in with ChatGPT - billing option added Sep 29: an eligible ChatGPT Plus or Pro plan pays for OpenAI-model usage in Devin Cloud, Desktop, and CLI, drawing on the Codex and ChatGPT Work usage already included in that plan. Available on Devin Pro, Max, and Teams. Source: Devin – Sign In With Chatgpt
• ACU (Agent Compute Unit) - the unit Cognition uses to chart monthly Devin usage in its Series E announcement; the chart shows steep growth from August 2025 to August 2026 but no absolute ACU counts or per-ACU pricing are published in the post. Source: Devin – Series E
• Code Scans - Devin feature introduced Sep 16 that turns a broad engineering goal ("update our auth logging") into an investigation across the codebase, evaluated findings, and a set of pull requests. Source: Devin – Introducing Code Scans
• SWE-2 free promotional period - SWE-2 is listed as free ("Slow" tier) in Devin Desktop and CLI through October 16, 2026 on the pricing page; in Devin Cloud, community reports and a Cognition employee put it at 75% off. No post-promo price is published. Sources: Windsurf – Pricing , News – Item
• Token-based billing / extra usage - paid plans can purchase usage beyond quota at per-model API rates shown only in the IDE's model picker, not on the public pricing page. Source: Windsurf – Pricing

Latest Changes

Changes since the 2026-08 report.

• New model: SWE-2 launched Sep 10, post-trained from Kimi K3 with an RL recipe that trains all reasoning-effort levels in one run. It scores 50.0% on FrontierCode 1.1 Main (vs 42.0% for SWE-1.7) and beats SWE-1.7 medium with 58% fewer turns and 81% lower cost. Source: Devin – Swe 2
• Funding: Series E of over $2B at a $48B valuation announced Sep 8, led by a16z and Accel, with Founders Fund, General Catalyst, and Avenir participating; run-rate revenue grew from $492M in May to almost $900M. Source: Devin – Series E
• Price cuts: Devin is now 30-40% cheaper in Fusion and Normal mode, 15-20% cheaper in Ultra, and up to 70% cheaper in Devin Review, from newer models plus a harness that batches tool calls and reuses cached context; Fusion tops FrontierCode 1.1 Extended at 68.8 for $0.60 per task on average. Source: Devin – More Efficient Devin
• New models (third-party): September added GPT-6 Astra (Sep 3), Grok 4.7 (Sep 21), GPT-6 Sol and GPT-6 Luna (Sep 22), Claude Opus 5.5 (Sep 22, the new #1 on FrontierCode 1.1 Extended), Claude Sonnet 5.5 (Sep 28, 64.4% on FrontierCode 1.1), and GPT-6.1 Sol (Sep 29, cache reads 95% off). Sources: Windsurf , Devin – Claude Opus 5 5 , Devin – Gpt 6 1 Sol
• Billing option: Sign in with ChatGPT (Sep 29) lets an eligible ChatGPT Plus or Pro subscription pay the OpenAI-model share of Devin sessions, with a configurable Devin limit in ChatGPT settings; Fusion with a GPT-6 Astra lead and free SWE-2 sidekick measures 39% cheaper than Astra alone on the Artificial Analysis Coding Agent Index. Source: Devin – Sign In With Chatgpt
• Feature added: Devin Plugins (Sep 9), built with BlackRock's engineering team, bundle skills, rules, MCP servers, hooks, and subagents with Git-based versioning and enterprise-level required/endorsed/forbidden declarations. Source: Devin – Governing Ai Agents At Scale With Blackrock
• Feature added: Code Scans (Sep 16) turn broad engineering goals into investigated, evaluated pull requests across a codebase. Source: Devin – Introducing Code Scans
• Platform expansion: Devin Cloud gained macOS/iOS build support (Sep 15), terminal control via devin --cloud or /cloud (Sep 21), and Microsoft Teams and Microsoft 365 integrations (Sep 23). Sources: Windsurf , Devin – Microsoft Teams And Microsoft 365
• Partnership: MongoDB AMP integration (Sep 29) embeds Devin in MongoDB's Application Modernization Platform for legacy-to-Atlas migrations. Source: Devin – Devin For Mongodb Modernizations
• Controversy: On Sep 30, Factory's CEO accused outgoing board adviser Chris Degnan of sharing confidential Factory information with Cognition; Degnan simultaneously joined Cognition as Chief Revenue Officer and denies wrongdoing. Source: TechCrunch – Factory Ceo Just Accused His Vc Board Advisor Of Spying For Cognition
• Upcoming (verified watch-items): the GPT-5.6 Sol 70% Devin discount ends October 3, 2026, and the SWE-2 free period ends October 16, 2026, with neither post-deadline price published. Sources: Devin – Gpt 5 6 Sol Promo , Windsurf – Pricing

Plans

Source: Windsurf – Pricing (page served at the windsurf.com URL is fully Devin-branded; all download/signup links point to devin.ai)

Usage allowance details: Quotas remain described only as "Light," "Increased," and "Significantly higher," refreshing "automatically on a daily and weekly basis," with no token counts, request limits, or credit amounts published anywhere on the pricing page or FAQ. The FAQ's cost-saving advice names specific small models (Haiku, GPT 5.2 Mini, Kimi K2.5) as quota extenders but gives no numbers. This is a continuity gap with June and August. Source: Windsurf – Pricing

Diff vs August: Plan structure and prices are unchanged (Free $0, Pro $20, Max $200, Teams $80 + $40/full seat). The free proprietary model line rotated from SWE-1.7 to SWE-2 with a hard end date of October 16, 2026. Enterprise features on the pricing page are unchanged (SAML/OIDC SSO, VPC, admin controls, teamspace isolation). Source: Windsurf – Pricing

Extra usage: Available on paid plans at per-model API rates shown only in the IDE's model picker. Source: Windsurf – Pricing

API Pricing

Devin does not offer standalone API access to SWE-2. A Cognition employee on HackerNews said keeping inference capacity for Devin products is preferred over OpenRouter distribution "atm," and another commenter noted there is not even a /v1/chat/completions endpoint. In Devin Cloud, SWE-2 is discounted 75%; on device (Desktop and CLI) it is free through October 16, 2026. Sources: News – Item , News – Item , Windsurf – Pricing

Per-token rates for third-party models inside Devin are visible only in the model picker. Two public list prices surfaced in September: GPT-6.1 Sol at $2/$10 per MTok with cache reads 95% off, and GPT-5.6 Sol lowered to $4/$20 per MTok list with the 70% Devin discount applied on top through October 3, 2026. Sources: Devin – Gpt 6 1 Sol , Devin – Gpt 5 6 Sol Price Drop

Published cost-per-task data (Cognition's own FrontierCode 1.1 measurements, the only public dollar figures):

Sources: Devin – More Efficient Devin , Devin – Fable 5 1 , Devin – Gpt 6 1 Sol , Devin – Gpt 6 Sol Luna

Relative cost claims: SWE-2 is 64% cheaper than Fable 5.1 at matched FrontierCode 1.1 Main scores; SWE-2 medium beats SWE-1.7 while costing 81% less on average; GPT-6 Sol matches GPT-5.6 Sol's FrontierCode 1.1 score at 61% lower cost per task; Claude Opus 5.5's per-task cost is less than a tenth of Fable 5's and about a sixth of GPT-6 Astra's; a typical Fable 5.1 FrontierCode task reads about 3M cached tokens, 70K uncached input tokens, and 21K output tokens, so over 95% of tokens are cache reads. Sources: Devin – Swe 2 , Devin – Gpt 6 Sol Luna , Devin – Claude Opus 5 5 , Devin – Fable 5 1

Model Performance / Benchmarks

SWE-2 launch table (Sep 10, 2026)

Source: Devin – Swe 2 . Methodology: publicly available results where they exist, otherwise internal harnesses (Claude Code for Anthropic models, Codex for OpenAI models, Grok Build for xAI models, Devin CLI for open-weight models), best score across reasoning efforts.

Efficiency data: SWE-2 medium makes its first real edit after a median of 18 steps vs 48 for SWE-1.7, and mean steps per FrontierCode 1.1 Main task drop from 127 (SWE-1.7) to 53 (SWE-2 medium). Source: Devin – Swe 2

September leaderboard claims (FrontierCode 1.1, self-reported)

• Claude Opus 5.5 (Sep 22): new #1 on FrontierCode 1.1 Extended, edging Fable 5 and GPT-6 Astra, at less than a tenth of Fable 5's cost per task; reaches fixes roughly 4x faster than Fable 5. Source: Devin – Claude Opus 5 5
• Claude Sonnet 5.5 (Sep 28): 64.4% on FrontierCode 1.1, "a significant improvement from Sonnet 5," surpassing Fable 5.1 at extra-high reasoning effort. Source: Devin – Claude Sonnet 5 5
• GPT-6 Astra (Sep 3): surpasses Fable 5.1, second only to Fable 5, at 64% lower cost. Source: Devin – Gpt 6 Astra
• GPT-6.1 Sol (Sep 29): matches GPT-6 Sol's FrontierCode 1.1 score at roughly half the cost per task at every reasoning effort; at low effort scores 58.1% for $0.21 per task, the best score of any model under $0.30. Source: Devin – Gpt 6 1 Sol
• Grok 4.7 (Sep 21): strongest on hard, multi-module backend tasks but trails Grok 4.6 on the aggregate because it tends to over-scope. Source: Devin – Grok 4 7
• Devin Fusion (Sep 28): leads FrontierCode 1.1 Extended at 68.8 for $0.60 per task average. Source: Devin – More Efficient Devin

Trustworthiness eval: SWE-2 passed 98.0% of politically sensitive questions (99.8% English, 95.2% Simplified Chinese, 99.1% Traditional Chinese) on Cognition's propaganda/censorship eval, and its context-dependent vulnerability eval showed no statistically significant framing effects. Source: Devin – Swe 2

Benchmark transparency note: FrontierCode tasks are not public, the leaderboard is run by Cognition in its own ecosystem, and the Terminal-Bench 2.1 (92.8%) vs Terminal-Bench 4 (27.3%) spread for SWE-2 became the community's central generalization concern (see Community Signals). Source: Devin – Frontiercode

Latest News

SWE-2 launched (September 10, 2026)

SWE-2 is Cognition's first multi-trillion-parameter RL model, post-trained from Kimi K3 with per-effort-level linear cost penalties tuned to the base model's Pareto frontier, a length-weighted reward baseline used since SWE-1.6, DSpark speculative decoding with an online-trained draft model, and NVFP4/FP8 quantization-aware training. It scores 50.0% on FrontierCode 1.1 Main, 73.0% on DeepSWE 1.1, and is free in Devin Desktop and CLI, rolling out to Devin Web and Fusion. Source: Devin – Swe 2

Series E: $2B at $48B (September 8, 2026)

Cognition raised over $2B at a $48B valuation led by a16z and Accel alongside Founders Fund, General Catalyst, and Avenir, with Benchmark, Kleiner Perkins, Lightspeed, T. Rowe Price, DST, and roughly 35 other investors participating. Run-rate revenue grew from $492M (May) to almost $900M; named customers include NVIDIA (chip design), GE Aerospace (aviation), Citi (financial services), Mercedes-Benz (automotive), and Modal (AI infrastructure). New offices this year: Washington D.C., Tokyo, Singapore, London, São Paulo, and Madrid, alongside San Francisco, New York, and Austin. The post also names Devin Auto-Triage (incident triage), Devin Security Swarm (vulnerability finding), and Devin Automations (event-driven triggers from Slack, GitHub, Linear). Source: Devin – Series E

Devin Plugins with BlackRock (September 9, 2026)

Plugins bundle skills, rules, MCP servers, hooks, and subagents into versioned, Git-backed units that enterprises can declare required, endorsed, or forbidden at enterprise, org, repo, or individual level, working across local and cloud agents. BlackRock shaped the governance model through its bread-kit framework (BlackRock Enterprise Agentic Development Kit); a BlackRock MD says bread-kit is now used by "every team that is coding" with new engineers onboarded onto it. Source: Devin – Governing Ai Agents At Scale With Blackrock

Code Scans and macOS support (September 15-16, 2026)

Code Scans convert broad engineering goals into concrete codebase-wide improvement PRs. Two days earlier, Devin Cloud gained macOS support, extending autonomous cloud development to iOS apps, native macOS applications, and Apple-tool-dependent projects. Sources: Devin – Introducing Code Scans , Windsurf

Six new models in Devin (September 3-29, 2026)

GPT-6 Astra (Sep 3), Grok 4.7 (Sep 21), GPT-6 Sol and GPT-6 Luna (Sep 22), Claude Opus 5.5 (Sep 22), Claude Sonnet 5.5 (Sep 28), and GPT-6.1 Sol (Sep 29) all went live in Devin Desktop and CLI during the month, each with Cognition-published FrontierCode 1.1 numbers (see Model Performance). The FrontierCode leaderboard changelog confirms the same add dates. Sources: Windsurf , Devin – Frontiercode

Devin in Microsoft Teams and Microsoft 365 (September 23, 2026)

Native @-mention support in Microsoft Teams plus a first-party Microsoft 365 integration connecting Devin to mail, calendar, files, tasks, chats, and directory. Source: Devin – Microsoft Teams And Microsoft 365

Sign in with ChatGPT and the cost-efficiency update (September 28-29, 2026)

Users on Devin Pro, Max, and Teams can pay OpenAI-model usage in Devin through an eligible ChatGPT Plus or Pro plan, with a configurable Devin cap in ChatGPT settings and fallback to Devin quota. GPT-6 Sol is available in Devin Cloud as a research preview. The parallel cost-efficiency update cut Devin usage costs 30-40% (Fusion and Normal), 15-20% (Ultra), and up to 70% (Devin Review), with Fusion leading FrontierCode 1.1 Extended at 68.8 for $0.60 per task. A MongoDB partnership (Sep 29) embeds Devin in MongoDB's Application Modernization Platform. Sources: Devin – Sign In With Chatgpt , Devin – More Efficient Devin , Devin – Devin For Mongodb Modernizations

Factory board-adviser dispute (September 30, 2026)

Factory CEO Matan Grinberg publicly accused Chris Degnan, a Factory board adviser and RPT Partners partner, of sharing confidential information with Cognition while negotiating a job there; Degnan joined Cognition as Chief Revenue Officer the same day and denies both firing and leakage. Vinod Khosla (an investor in both companies) called Factory a "struggling second tier competitor," and Cognition CEO Scott Wu responded that Cognition has "no interest in Factory's info." Cognition's other customers per TechCrunch include NASA and Goldman Sachs. Source: TechCrunch – Factory Ceo Just Accused His Vc Board Advisor Of Spying For Cognition

Late-August context that shaped September: Fable 5.1 arrived in Devin Aug 31 with Fable-level cost per task dropping 54% versus Fable 5 ($2.68 vs $5.84 on FrontierCode 1.1 Extended) due to the $0.25/MTok cache-read rate, and Fable 5/5.1 became usable under zero data retention via a time-bound exemption while Anthropic's Enterprise Frontier Safeguards rolls out. GPT-5.6 Sol's list price fell to $4/$20 per MTok on Aug 21, with the 70% Devin discount running through Oct 3, 2026. Sources: Devin – Fable 5 1 , Devin – Gpt 5 6 Sol Price Drop

Community Signals

SWE-2 launch: benchmark skepticism tops a 447-point thread

The SWE-2 launch was the month's highest-engagement Cognition story on HackerNews (447 points, 194 comments). The dominant theme was the Terminal-Bench 2.1 vs Terminal-Bench 4 split. postalcoder: "If you're looking for reason to be skeptical, look no further than the massive delta between the Terminal Bench 2.1 (92.8%) and the Terminal Bench 4 score (27.3%). Terminal Bench 4 was released a couple weeks ago, so the difference you're seeing between the two scores can be interpreted as 'how well does this model generalize to new problems'? More crudely: 'how benchmaxxed is this model?'" News – Item . mediaman pushed back: "This is a groundless criticism. TB2.1 is saturated. TB4 is not. Sol xhigh is 90% on TB2.1 but 37% on TB4. Is it also 'benchmaxxed'?" News – Item . thereitgoes456 attacked the venue itself: "It is rivaling Astra, on their own benchmark that they made (FrontierCode), that they ran themselves in their own closed-source ecosystem that isn't reproducible by anyone." News – Item . fallingbananna supplied comparative TB4 context: "Those 27.3% are still in the ballpark of modern models: Sonnet 5 - 12.4%, Luna - 17.3%, Grok 4.6 - 20.3%, Sol - 37.3%, GLM 5.3 - 41.8%, Opus 5 - 51.8%." News – Item . Thread: News – Item

Availability and free-tier confusion in the same thread

Cognition employee samyok stated: "SWE-2 is free to use for users like yourself for the next month, and almost all usage should be supported via our CLI. Disclaimer: I work at Cognition, although was not involved in SWE-2." News – Item . randomblock1's experience differed by surface: "I just gave it a try and it doesn't appear to be free, it used up some of my on demand usage. It does say 75% off though. Seems like for Pro subscribers SWE-1.7 is free, maybe SWE-2 is free for them?" News – Item , later adding "No it still requires Pro in the CLI. Only free model is SWE-1.6 slow." News – Item . The lack of a standalone API drew direct criticism from wren6991: "Your own CLI? Not even a /v1/chat/completions API? Is your business model based on pretending LLMs are not an interchangeable commodity already?" News – Item . A paying convert, InsideOutSanta: "I bought the 20$ subscription and have been using SWE-2 for a few days now, and it's actually good. I don't think it's Fable-class, but SWE-2 Max feels substantially better than [what I expected]." News – Item

Series E reception: valuation skepticism and a defender (24 points, 12 comments)

edude03 questioned the product's standing: "Devin was the first ai developer harness I ever heard of... Now it seems like the product has faded (into irrelevance?) between other harnesses like cursor especially and all the major harnesses having a cloud mode. Is there some other area Devin has become really popular / has stayed competitive?" News – Item . steve-atx-7600 focused on the number: "Seems insane... struggling to see where Devin adds $2 billion value. Edit 48billion I just noticed. Someone's getting fleeced." News – Item . wordpad argued the enterprise moat: "They have a first mover advantage on autonomous AI employee space. So big enterprises will all default to them given all their competitors will be 'startups' uncertain to be around long term." News – Item . vvern offered a concise reversal: "I used to be a hater, but it's kinda good now." News – Item . Thread: News – Item

Other September signals

A third-party page on SWE-2's Terminal-Bench 2.1 score drew 69 points and 27 comments: News – Item . Dioxus Labs (YC S23) announced it is joining Cognition (8 points): News – Item . Late-August context: Bloomberg reported SpaceX attempted to acquire Cognition (7 points, News – Item ), which the CEO denied the next day (News – Item). A Show HN launched "Engrams, an open source alternative to Devin" (17 points): News – Item

Failed sources

The Reddit search (old.reddit.com/search/?q=windsurf+devin) was blocked by a login wall this cycle and could not be used; no Reddit quotes are included as a result. All HN quotes above were retrieved via the HN Algolia API with direct permalinks.

Reddit recovery (added 2026-10-03)

A logged-out Reddit recovery pass (October 3) found no Devin threads in the month's top results (matches were sports and politics). Reddit footprint remains tiny for a $48B-valuation product: r/DevinAI counts 1.3K weekly visitors with 23 weekly contributions (captured 2026-10-03). Reddit – Devinai

Enterprise Readiness

Terms explained:

• SCIM - a protocol for automatically provisioning and deprovisioning user accounts from a corporate directory (e.g., Okta, Azure AD) to a SaaS tool. Datatracker – Rfc7644
• MultiDevin - enterprise feature where "Manager" Devins delegate to parallel "worker" Devins for large task backlogs. Source: Devin – Enterprise
• Forward Deployed Engineer - a Cognition engineer assigned to an enterprise customer for hands-on implementation, listed as an enterprise entitlement. Source: Devin – Enterprise

Transparency Gaps