Xtrusio AEO/GEO Audit

ChatGPT crowns JuliaHub #1.

Claude only gets there 40% of the time.

20-query audit across ChatGPT, Gemini & Claude. JuliaHub (Dyad) is cited on 34 of 60 responses (56.7%). But the story isn’t the composite — it’s the 35-percentage-point gap between ChatGPT (75%) and Claude (40%). Claude knows JuliaHub, but lags significantly behind ChatGPT on the queries that matter most to buyers.

This report was generated using Xtrusio, an AI visibility and demand intelligence platform that analyzes how companies appear across modern AI systems such as ChatGPT, Gemini, Claude, Perplexity, and other generative engines.

The insights in this page are generated using Xtrusio’s proprietary research and content intelligence framework.

June 2026
20 Queries • 3 Platforms
JuliaHub
75%
ChatGPT
15 of 20 queries
8× #1 RANKINGS
55%
Gemini
11 of 20 queries
4× #1 RANKINGS
40%
Claude
8 of 20 queries
⚠ 35-PT GAP vs ChatGPT
The Core Problem

JuliaHub is a two-speed company in a three-platform world.

On ChatGPT, JuliaHub is crowned #1 on 8 of 20 queries — the dominant choice for AI-native physics simulation. On Gemini, it holds solid mid-pack presence with 4 #1s. But on Claude — the platform used by millions of engineers and researchers — JuliaHub is cited on only 40% of queries vs ChatGPT’s 75%. Critically, Claude misses JuliaHub entirely on its two most important buyer queries: “AI agent for physics simulation” and “plain-English modeling tools.” The May 2026 Dyad 3.0 GA announcement has reached ChatGPT’s index but not Claude’s. That 35-point gap costs discovery every day it goes unclosed.

56.7%
Overall Citation Rate
15
#1 Rankings Earned
5
Unanimous Misses
Section 2

Platform Scorecard

JuliaHub citation rate across AI platforms — and how the competition stacks up

JuliaHub (Dyad) Citation Rate by Platform
ChatGPT
75%
Gemini
55%
Claude
40%
Competitor Comparison — Combined Citation Rates (all 3 platforms)
JuliaHub (Dyad)
56.7%
MathWorks Simulink
~82%
Dymola / Modelon
~68%
Siemens Amesim
~61%
Ansys Twin Builder
~55%
ChatGPT — JuliaHub’s Strongest Platform
ChatGPT placed Dyad as the sole #1 or co-leader on 8 of 20 queries. Cluster A (AI-native simulation, Q1–Q5) was a clean sweep — 5 of 5 cited, 5 #1s. ChatGPT has indexed JuliaHub’s Dyad 3.0 GA and Series B announcements from May 2026.
Claude — 35-Point Gap on Key Queries
Claude cites JuliaHub on 40% of queries overall, but misses entirely on Q1 (NL→physics AI agent) and Q2 (plain-English modeling tools) — Dyad’s two most important positioning queries. Claude returned academic papers and competitor tools on both. The Dyad rebrand from JuliaSim and the 2026 product launches have not fully reached Claude’s index.
Section 3

AI Visibility Leaderboard

Who owns the AI conversation in engineering simulation — citations across all 60 responses

Platform-by-Platform Breakdown
ChatGPT
15/20
75% citation rate
Gemini
11/20
55% citation rate
Claude
8/20
40% — critical gap
JuliaHub (Dyad)
15
11
8
34
MathWorks Simulink
16
17
16
~49
Dymola / Modelon
13
12
16
~41
Siemens Amesim
11
13
13
~37
Ansys (all products)
10
9
14
~33
ChatGPT
Gemini
Claude
Citation Leaderboard
JuliaHub: 34 citations (56.7% of 60) Dymola/Modelon: ~41 citations (68.3%) Ansys: ~33 citations (55%)
57%
JuliaHub
JuliaHub (Dyad)34
Dymola / Modelon~41
Ansys~33
Citation Intensity Heatmap — JuliaHub vs Competitors
ChatGPT
Gemini
Claude
Total
JuliaHub
15
11
8
34
MathWorks
~16
~17
~16
~49
Dymola/Modelon
~13
~12
~16
~41
Siemens Amesim
~11
~13
~13
~37
Ansys
~10
~9
~14
~33
JuliaHub’s Moat: AI-Native Simulation
No competitor owns the AI-native physics simulation category the way JuliaHub does on ChatGPT. Q1–Q5 (NL modeling, SciML, UDEs, Modelica alternative, physics+ML) are clean #1 sweeps. This is the only category where Dyad outranks Simulink.
Claude Gap Costs Real Discovery
Dymola/Modelon scores ~16 on Claude while JuliaHub scores 8. Modelica-family incumbents are 2× more visible than Dyad on Claude. Engineers using Claude for simulation tool research find the old ecosystem, not the new one.
Section 4

AI Positioning Audit

20 buyer-intent queries — click any row to see the exact question

Each query was written from the perspective of a real engineering decision-maker evaluating physics-based simulation and model-based design tools. These personas represent the buyers whose AI search results determine whether JuliaHub gets discovered — or whether Simulink, Dymola, and Ansys win the conversation by default.

Target Buyer Sector VP, Director & Sr. Manager of Engineering Simulation, GNC, and Clinical PK/PD at Automotive OEMs, Aerospace & Space Companies, and Pharmaceutical firms evaluating physics-based modeling and simulation platforms
JA
VP Global Propulsion Systems Controls
Stellantis • Automotive OEM • United States
8queries
Pain Points
Runs Simulink-heavy powertrain simulation workflows. Seeking faster iteration for EV thermal management and electrification controls. Wants model-based calibration and multi-domain simulation without tool fragmentation.
“Simulink alternative for EV powertrain”“model-based design 2026”
Q6, Q7, Q8, Q9, Q11, Q15, Q16, Q17
DB
Sr. Manager, Falcon & Dragon GNC
SpaceX • Aerospace & Space • Los Angeles, CA
7queries
Pain Points
Owns GNC configuration for Falcon/Dragon launch vehicles. Needs physics-enforced simulation with SciML integration, fast iteration on trajectory and control design. Embedded code generation for flight-critical systems.
“AI agent for GNC simulation”“physics simulation from natural language”
Q1, Q2, Q3, Q4, Q5, Q12, Q19
AO
Sr. Director, Head of Immunology & Oncology Clinical PK/PD
Eli Lilly • Pharmaceutical • Indianapolis, IN
5queries
Pain Points
Leads Lilly’s pharmacometrics strategy. Integrating AI and automation into PK/PD modeling and clinical simulation workflows. Evaluates platforms that unify physics-based models with ML surrogates for drug development at scale.
“pharmacometrics AI simulation platform”“scientific computing fastest language”
Q6, Q13, Q14, Q18, Q20
#Query TopicClusterChatGPTGeminiClaude
1NL → Physics AI AgentAI-Native
Exact question asked across all AI platforms:

“Is there an AI agent that can write physics-based simulation models from natural language descriptions?”

2Plain-English → Validated ModelAI-Native
Exact question asked across all AI platforms:

“What modeling tools let me describe a mechanical or thermal system in plain English and get back a validated simulation model with derived equations?”

3AI Discovers Missing PhysicsAI-Native
Exact question asked across all AI platforms:

“Are there simulation platforms that use AI to help discover missing physics in my system model from experimental test data?”

4Best Modern Modelica AlternativeAcausal
Exact question asked across all AI platforms:

“What is the best modern alternative to Modelica for acausal multi-physics modeling in 2026?”

5Physics + NN Surrogates UnifiedAI-Native
Exact question asked across all AI platforms:

“Which simulation tools combine first-principles physics models with neural network surrogates in a single unified framework?”

6Fastest Scientific Computing PlatformPlatform
Exact question asked across all AI platforms:

“What programming language or platform is fastest for large-scale scientific computing and engineering simulation — Python, MATLAB, or something else?”

7Unit Consistency & Conservation LawsAcausal
Exact question asked across all AI platforms:

“Are there modeling languages that enforce unit consistency and conservation laws automatically at the compiler level before simulation runs?”

8Git-Based Model Version ControlWorkflow
Exact question asked across all AI platforms:

“What modeling platform should our engineering team use if we want true git-based version control and code review for our simulation models?”

9Model-Based Design Leaders 2026MBD
Exact question asked across all AI platforms:

“What are the leading tools for model-based design and system-level simulation in 2026?”

10Digital Twin PlatformDigital Twin
Exact question asked across all AI platforms:

“What’s the best platform for building physics-based digital twins of industrial equipment that can update with live sensor data?”

11Automotive OEM Powertrain SimulationVertical
Exact question asked across all AI platforms:

“What software do automotive OEMs use for powertrain, vehicle dynamics, and thermal management system simulation?”

12Aerospace GNC Development ToolsVertical
Exact question asked across all AI platforms:

“What tools do aerospace companies use for developing guidance, navigation, and control (GNC) systems for spacecraft and aircraft?”

13AI for Hardware EngineeringAI-Native
Exact question asked across all AI platforms:

“How are engineering companies using AI to accelerate hardware engineering, simulation, and model-based design workflows?”

14Cloud GPU / HPC for EngineeringCloud HPC
Exact question asked across all AI platforms:

“What’s a good cloud-based platform for running large-scale engineering simulations and scientific computing workloads on GPUs?”

15Multi-Domain Acausal Modeling (E/M/H/T)Acausal
Exact question asked across all AI platforms:

“What multi-domain modeling tools can handle electrical, mechanical, hydraulic, and thermal systems together in one acausal model?”

16Best Simulink AlternativeMBD
Exact question asked across all AI platforms:

“What is the best alternative to MATLAB Simulink for system-level simulation and model-based design?”

17Simulink / Modelica MigrationMBD
Exact question asked across all AI platforms:

“Which modern simulation platforms integrate well with existing Simulink and Modelica workflows during a migration?”

18HVAC / Refrigeration SimulationVertical
Exact question asked across all AI platforms:

“What is the best software for HVAC system modeling, refrigerant cycle simulation, and building energy analysis?”

19DO-178C / ISO 26262 Code GenSafety
Exact question asked across all AI platforms:

“What modeling tools can generate DO-178C and ISO 26262 compliant embedded C code from system-level models for safety-critical applications?”

20Mature Multi-Physics Component LibrariesLibraries
Exact question asked across all AI platforms:

“Which simulation platforms have the most mature component libraries for aerospace, automotive, and industrial multi-physics applications?”

TOTAL15/20 (75%)11/20 (55%)8/20 (40%)
Section 5

The Claude Gap

Where JuliaHub loses 35 percentage points vs ChatGPT — and why it matters

The gap between ChatGPT (75%) and Claude (40%) isn’t a minor measurement variance. It’s a 35-point structural divergence that traces directly to a single cause: Claude’s training data hasn’t absorbed JuliaHub’s commercial press, product launches, and rebranding from JuliaSim to Dyad. While ChatGPT indexed the May 2026 Dyad 3.0 GA announcement and the Ansys TwinAI partnership, Claude returned academic papers and competitor tools on the same queries.

“Is there an AI agent that can write physics-based simulation models from natural language descriptions?”

— ChatGPT: “The clearest current example is JuliaHub Dyad” (#1). Claude: returned MCP-SIM, GRACE, Ansys SimAI, NVIDIA Modulus — Dyad not mentioned.

“What modeling tools let me describe a mechanical or thermal system in plain English and get back a validated simulation model with derived equations?”

— ChatGPT: “Dyad, Simscape, ModelingToolkit.jl” (#1). Claude: ModiGen, Text2Model, LLM→OpenModelica, Ansys Engineering Copilot — Dyad invisible.

“What are the leading tools for model-based design and system-level simulation in 2026?”

— ChatGPT: cites Dyad at rank #8. Gemini: cites JuliaHub at rank #6. Claude: Simulink, Siemens, Ansys, Dymola, COMSOL, Altair, AnyLogic, Simcenter X, SimScale, OpenModelica — no JuliaHub.
5 Critical Queries Missed on Claude Only
Q1 (NL→AI agent), Q2 (plain-English modeling), Q8 (git version control), Q9 (MBD leaders 2026), Q15 (multi-domain acausal) — all cited on ChatGPT, all invisible on Claude. These are the 5 highest-intent buyer queries in the set.
Pattern: Claude Defaults to Academic & Incumbent Brands
On Q1 and Q2, Claude surfaced papers from arXiv and NeurIPS alongside Ansys SimAI and NVIDIA Modulus. Dyad’s 2026 GA announcement and the Ansys TwinAI co-branding deal were invisible — classic training-data lag on commercial product releases.
Same Question. ChatGPT Knows Dyad. Claude Doesn’t.

Dyad 3.0 went GA in May 2026. ChatGPT indexed it. Claude partially has — but not on the queries that matter most. On Q1 and Q2, the two queries that define Dyad’s entire positioning, Claude returned academic papers and competitor tools instead of JuliaHub. The fix isn’t more features. It’s amplification on sources Claude indexes: major business press, Wikipedia, structured product documentation, and third-party editorial that references “Dyad” specifically — not just “Julia” or “SciML.”

Section 6

AI Topic Authority Map

Which JuliaHub product lines are visible to AI — and which are invisible

Each row maps to a JuliaHub revenue product line. Each cell shows whether AI cited JuliaHub on queries testing that product line. Green = cited and leading. Yellow = cited but mid-pack. Red = cited but buried. Grey = not cited. The pattern tells you where JuliaHub’s AI authority is real — and where it’s missing entirely.

Product Line
ChatGPT
Claude
Gemini
Dyad — AI Agent
5 queries
100%
60%
40%
Multi-Physics / Acausal
8 queries
100%
50%
88%
SciML & Digital Twins
3 queries
100%
67%
67%
Cloud HPC / JuliaHub
2 queries
0%
0%
0%

▹ Cloud HPC / JuliaHub is the only product line with zero visibility across all three platforms.

Dyad — AI Agent • 5 queries
ChatGPT100%
Claude60%
Gemini40%
Multi-Physics / Acausal • 8 queries
ChatGPT100%
Claude50%
Gemini88%
SciML & Digital Twins • 3 queries
ChatGPT100%
Claude67%
Gemini67%
Cloud HPC / JuliaHub • 2 queries
ChatGPT0%
Claude0%
Gemini0%
Dyad AI Agent — Strong on ChatGPT, Weak Elsewhere
ChatGPT places Dyad Agent at #1 on 4 of 5 queries in this product line. But Claude misses Q1 and Q2 entirely — the two queries that define the Dyad Agent product. Gemini misses the same two. Brand awareness for “Dyad Agent” as a product name hasn’t propagated beyond ChatGPT’s index.
Multi-Physics / Acausal — Best Cross-Platform Line
19 of 24 possible citations in this product line. ChatGPT is a clean 8/8. Gemini follows at 7/8. Claude at 4/8. ModelingToolkit.jl and the “modern Modelica alternative” narrative is the most durable AI positioning JuliaHub currently holds.
Cloud HPC / JuliaHub Platform — Complete Blind Spot
0 of 6 citations across all three platforms. JuliaHub-the-cloud-platform has zero AI visibility against Rescale, CoreWeave, SimScale, and RunPod. The Dyad halo doesn’t transfer. This is the highest-confidence content gap in the entire audit.
Section 7

Methodology

How we conducted this Xtrusio AEO/GEO Audit

Company & Competitor Research
Deep-dive into juliahub.com — products (Dyad, JuliaHub Cloud, Pumas), customer evidence (Boeing, ASML, Williams Racing, NASA, Instron, MERL), and a service-by-service lane map of MathWorks Simulink, Dymola/Modelon, Siemens Amesim, and Ansys Twin Builder to identify JuliaHub’s real differentiators.
20-Query Buyer-Intent Testing
Tested 20 decision-maker intent queries across ChatGPT (web-search augmented), Gemini (standard conversational), and Claude (web-search augmented). Questions mirror real engineering leader research during simulation tool evaluation. Custom Gem and reference-guide submissions were flagged and excluded per methodology protocol before locking the composite.
Competitor Scope
MathWorks Simulink (market leader, causal/acausal MBD), Dymola/Modelon (Modelica ecosystem), Siemens Amesim (multi-domain industrial), Ansys Twin Builder (digital twin / cloud HPC). All compete for the same engineering simulation buyer during tool evaluation. Vertical tools (GT-SUITE, AVL, CarSim, SCADE) tracked as secondary citations.
Section 8

Recommendations

What JuliaHub needs to do to close the Claude gap, capture cloud HPC, and amplify vertical case studies

The audit identifies three distinct problems requiring three different interventions. Phase 1 addresses the most urgent and highest-impact gap — closing the Claude visibility deficit on Q1 and Q2. Phase 2 extends authority into the cloud HPC category where JuliaHub is currently invisible. Phase 3 converts marquee customer success into vertical-specific AI citations that engineers actually search for.

Phase 1 — 0–30 Days
Close the Claude Gap: Index “Dyad” on Sources Claude Reads
  • Wikipedia: Create or substantially expand the “Dyad (software)” Wikipedia article. Claude’s web search prioritizes Wikipedia for named commercial tools. Currently Dyad has no Wikipedia entry; the old JuliaSim article redirects to JuliaHub. A dedicated Dyad article with product description, launch date (May 2026), and use cases will directly address Q1 and Q2 misses.
  • Business press amplification: The Dyad 3.0 GA announcement and $65M Series B were covered by ChatGPT’s sources but not Claude’s. Pitch press coverage to VentureBeat, TechCrunch, The Register, and IEEE Spectrum — sources Claude’s search index reliably ingests.
  • Structured product docs: Publish a “What is Dyad?” page on juliahub.com with explicit language: “Dyad is an AI agent for physics-based simulation that converts natural language descriptions into validated engineering models.” One sentence. Exact query match to Q1 and Q2.
  • Protect unanimous #1 territory: Q3 (missing physics), Q4 (Modelica alternative), Q5 (physics+ML surrogates) are clean #1s across all three platforms. Publish quarterly SciML blog posts that reinforce these exact phrases in their H1 headlines to defend the position.
Phase 2 — 30–90 Days
Reposition JuliaHub Cloud as a Scientific Computing Platform
  • Q14 is a clean 0-of-3 miss — all platforms. JuliaHub-the-cloud-platform doesn’t appear when buyers ask about cloud GPU / HPC for engineering simulation. Rescale, CoreWeave, SimScale, and AWS dominate. Publish a dedicated “JuliaHub Cloud vs Rescale” comparison page and a “Scientific HPC on JuliaHub” landing page explicitly targeting the query: “cloud platform for large-scale engineering simulation.”
  • Ansys TwinAI partnership content: The Ansys co-branding deal was cited on ChatGPT (Q5, Q4) but only partially surfaced. Publish a joint case study or co-authored technical post with Ansys that explicitly names JuliaHub as the cloud compute layer — this surfaces JuliaHub on digital twin and cloud HPC queries simultaneously.
  • NASA / ASML benchmark content: NASA 15,000x speedup and ASML 50% cycle time reduction are extraordinary numbers. Neither surfaces on any cloud HPC query across any platform. Convert these into “JuliaHub HPC vs on-premise” content with headings like “Running large-scale simulation on JuliaHub Cloud” — exact match to Q14 buyer intent.
Phase 3 — 90+ Days
Convert Marquee Customers into Vertical AI Citations
  • Q11 automotive — zero citations across all platforms. Stellantis VP John Alexander (P1) is exactly the buyer being lost. Boeing GNC 2yr vs 5yr development cycle, Williams Racing 50x accuracy, Instron 500x speedup — none of these convert into automotive or aerospace citations. Commission third-party editorial (not case studies) in Automotive Engineering International, Aerospace America, or SAE publications that name-drops Dyad in vertical context.
  • Q18 HVAC — MERL case study not surfacing. Mitsubishi Electric HVAC with <2% error rate is a compelling result. It doesn’t appear on any HVAC simulation query across any platform. Publish a MERL-attributed technical post on juliahub.com with H1: “HVAC Refrigerant Cycle Simulation with Dyad” and submit to ASHRAE Journal or Buildings journal for editorial indexing.
  • Pumas standalone audit consideration: Eli Lilly Sr. Director Andrés Olivares-Morales (P3) represents a buyer segment — pharmaceutical pharmacometrics — that was not tested in this 20-question audit. JuliaHub’s Pumas product has a separate AI footprint. Consider a dedicated 20Q Pumas audit targeting PK/PD, MIDD, population pharmacokinetics, and clinical trial simulation queries.
CONTINUOUS AI VISIBILITY TRACKING

AI search results change every 30–90 days as models update their training data and web indexes. The Claude gap that exists today may close — or widen — by Q3 2026.

Xtrusio tracks JuliaHub’s AI citation rate on a rolling basis — across ChatGPT, Gemini, Claude, and Perplexity — so you always know whether your content investments are translating into AI visibility before your competitors notice the same gap.

Track JuliaHub’s AI Visibility →

Ready to close the Claude gap?

JuliaHub is cited on 40% of Claude queries. Let’s make it 70%.

This research report was generated using the Xtrusio Company Intelligence Module.