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The AI Stack Weekly

Issue 01 · Week 17 of 2026.

/Industry brief · ~7 min read/Public sources onlyDownload brief

The Bottom Line

The marginal dollar at every layer earns less. Except the network.

Flywheel arcAll three lenses

Capital is still flooding the AI stack, but the marginal dollar earns less than the prior dollar at every layer except one. Hyperscalers are deploying ~$700B of 2026 capex against ~$120B of AI-attributable revenue — a ratio that gets tested when Microsoft, Google, Meta, and Amazon all print Q1 between April 29 and May 6. Frontier labs are committing forward compute at multiples of their disclosed revenue. The on-prem floor moved up sharply this week with DeepSeek V4 (open weights, frontier-class on coding), reshaping enterprise procurement: the question is no longer whether to self-host frontier capability, but which workload to move and on what fabric. The durable winner of the buildout is the network and interconnect layer that connects cloud, neocloud, and on-prem for hybrid AI — the only layer where pricing power compounds rather than compresses.

JevonsMetcalfeGilderSoftwareJevonsHardwareHuangNetworkingMetcalfe + Gilder

The three lenses

What moved this week, and what to do about it.

9 events across the flywheel — 3 software, 3 hardware, 3 networking.

Software.

  • DeepSeek V4 released — MIT-licensed, 1.6T MoE, 1M context, frontier-class on coding

    HuggingFace, deepseek.com

  • Open-weight models lead closed on SWE-Bench Pro — Kimi K2.6 58.6 and GLM-5.1 58.4 vs GPT-5.4 57.7 and Opus 4.6 57.3

    Artificial Analysis, HuggingFace model cards

  • Anthropic withholds 'Mythos' flagship on cyber-capability grounds; UK AISI confirms autonomous offensive capability

    anthropic.com, red.anthropic.com, aisi.gov.uk

What this means

Open weights crossing the closed frontier on coding moves the on-prem question from 'can we?' to 'which workload first?' Procurement should pull DeepSeek V4 and the leading open coding models into pilot this quarter; merchant-vs-self-host is now a real fork, not a hypothetical. Anthropic withholding Mythos on cyber-risk is the new diligence signal — vendor-risk frameworks need a capability-gate criterion, not just an availability SLA.

Hardware.

  • NVIDIA Vera Rubin engineering samples shipping to customers within 12 months of Blackwell Ultra GA — half the prior generation gap

    NVIDIA developer channels, multiple OEM disclosures

  • Custom silicon share of incremental AI compute reaches ~30%, up from ~22% three months ago

    TrendForce, SemiAnalysis

  • HBM4 validation milestones at SK Hynix, Samsung, and Micron — primary risk for H2 2026 hyperscaler tail

    TrendForce, vendor advisories

What this means

Vera Rubin samples landing 12 months after Blackwell Ultra means refresh planning needs to shift from a 24-month to a 14-16-month cycle; standard depreciation schedules are now wrong for AI silicon. The binding constraint is power, packaging, and HBM4, not GPUs themselves — buyers should secure HBM allocation and grid interconnect alongside chips, not after. Custom silicon at ~30% of incremental compute is the threshold where merchant-GPU pricing power starts to compress; expect single-vendor leverage to fade through 2026.

Networking.

  • Equinix Fabric Intelligence launch creates AI-native networking as a distinct product category

    Equinix press, Light Reading

  • NVLink Fusion + UALink standardization moves cross-vendor scale-up fabric toward an interoperable baseline

    NVIDIA, AMD, Intel joint statements; OCP working group

  • 1.6 Tbps and co-packaged optics shipping in volume ahead of the compute they serve — Gilder's Law in motion

    Marvell, Broadcom press; OIF working notes

What this means

Equinix Fabric Intelligence formalizes AI-native interconnect as its own product category — investors should track cross-connect and fabric revenue as a leading indicator that decouples from raw colo capacity. NVLink Fusion plus UALink means architects can stop betting on a single vendor's scale-up fabric; multi-vendor, mixed-silicon clusters are now a real design target. With 1.6 Tbps optics shipping ahead of the compute they serve, the network is no longer the bottleneck for hybrid AI — designs targeting multi-DC training in 2027 should plan around fabric headroom, not fabric scarcity.

Capital flow

Money in, revenue out.

4 categories tracked. Capital deployment up in 4 of 4; revenue follows at multiples of 0.21 to 0.6.

The four-category scorecard. Where capital is going in, where revenue is coming out, and how much of it is real. The one chart for the boardroom.

  • Frontier Labs

    OpenAI, Anthropic, Google DeepMind, xAI

    Capital In

    ~$50B

    vs ~$30B

    Revenue Out

    ~$30B

    vs ~$25B

    Burn / Rev

    0.6

    Movement

    Anthropic +8.5 GW across NVIDIA, Trainium, TPU — forward-buy that locks in vendor diversity and outruns disclosed demand.

  • Hyperscaler-Hosted

    AWS Bedrock, Azure Foundry, Vertex, OCI

    Capital In

    ~$48B

    vs ~$30B

    Revenue Out

    ~$10B

    vs ~$8B

    Burn / Rev

    0.21

    Movement

    Microsoft absorbs ~1.6 GW from Stargate Abilene — orphaned frontier capacity rerouted into hyperscaler platforms.

  • Neoclouds

    CoreWeave, Crusoe, Nebius, Applied Digital

    Capital In

    ~$15B

    vs ~$10B

    Revenue Out

    $1.6B

    vs $1.1B

    Burn / Rev

    0.4

    Movement

    CoreWeave backlog +4x YoY to $66.8B (incl. Meta $21B six-year) — conversion velocity is now the metric, not gross backlog.

  • On-Prem / Hybrid

    Enterprise GPU clusters, sovereign and national programs

    Capital In

    ~$42B

    vs ~$25B

    Revenue Out

    Indirect

    vs Indirect

    Burn / Rev

    n/a

    Movement

    DeepSeek V4 open crosses frontier; sovereign programs surge — workload migration from rented to owned compute has a frontier-class trigger.

Burn-to-Revenue is revenue divided by committed capital. Lower means more capital is going out than coming in.

Signal vs noise

What’s real, what’s noise.

5 claims this week — 4 signal, 1 noise.

Each claim is scored 1–5 on source quality and triangulation. Anything 2 or below is flagged as noise. Where consensus is wrong, we say so.

  • 5 / 5

    Anthropic has committed to ~8.5+ GW of forward compute capacity across NVIDIA, AWS Trainium, and Google TPU.

    Sources: anthropic.com (Apr 20 + Apr 7), AWS news, Verge, Broadcom 8-K, multiple SEC filings

    Real. The largest single-counterparty compute commitment ever recorded. Distributed across three platforms reduces single-vendor dependency and is critical evidence for the all-three-lenses thesis.

  • 4 / 5

    Aggregate 2026 hyperscaler capex tracking ~$700B (Microsoft + Google + Meta + Amazon + Oracle).

    Sources: Composite of Q4 2025 earnings guides; not a single sourced number

    Directionally correct. Will likely revise upward on Q1 2026 prints (Apr 29 - May 6). Caution: the aggregate hides per-company variance — Microsoft is decelerating Azure guidance while Google capex still accelerates.

  • 2 / 5 — noise

    DeepSeek V4 was trained end-to-end on Huawei Ascend silicon, eliminating NVIDIA dependency.

    Sources: Chinese-language tech blogs only. No primary DeepSeek confirmation.

    Noise. Significant if true (sovereign-AI hardware decoupling milestone) but unverified. Watch for any DeepSeek primary source. If confirmed, this advances the on-prem-via-non-Western-stack thesis materially.

  • 4 / 5

    Anthropic withheld 'Mythos' on cyber-risk; UK AISI confirmed autonomous offensive capability.

    Sources: anthropic.com, red.anthropic.com, aisi.gov.uk, Cloud Security Alliance

    Real. First major lab to deliberately withhold a flagship on capability-risk grounds. Procurement diligence implications: cyber-capability gating becomes a vendor-risk criterion.

  • 5 / 5

    Open-weight models now lead closed models on credible coding benchmarks.

    Sources: HuggingFace model cards (Kimi K2.6, GLM-5.1), Artificial Analysis, multiple independent evals

    Real. SWE-Bench Pro: Kimi K2.6 58.6, GLM-5.1 58.4 vs GPT-5.4 57.7, Opus 4.6 57.3. First time open leads closed on a credible code benchmark. The on-prem demand catalyst for the open-weights hypothesis.

Early warning panel

The levers we monitor.

10 metrics tracked — 8 rising, 2 falling.

Current vs prior period. Each metric has a threshold where the read materially changes — this panel flags the inflection before it lands in headlines. Click any metric for the methodology and this-week read.

  • Frontier lab cash position (avg months runway, top 3)

    ~22 movs ~26 mo

    Threshold: <18 mo triggers re-rating risk

    What this measures

    Top 3 frontier labs (OpenAI, Anthropic, Google DeepMind) by disclosed runway, computed from cash on hand divided by trailing-12-month operating burn. The drop from ~26 to ~22 months reflects accelerating compute commitments outpacing revenue growth. <18 months triggers re-rating risk — investor models start pricing dilution or strategic exit; <12 months forces consolidation, acquisition, or revenue reset.

  • Hyperscaler capex / AI revenue ratio (top 4 weighted)

    ~5.5vs ~4.8

    Threshold: >6.0 invites investor pushback at next earnings

    What this measures

    Top 4 hyperscalers (MSFT, GOOG, META, AMZN) weighted aggregate of total capex divided by AI-attributable revenue. ~5.5 means $5.50 of capex deployed per $1 of AI-attributable revenue. >6.0 is the threshold where sell-side analysts stop accepting the platform-pull-through narrative; sustained 5.5x+ is the wedge against capital-efficiency claims.

  • CoreWeave revenue backlog

    $66.8Bvs $15.1B

    Threshold: Conversion velocity matters more than gross figure

    What this measures

    Booked but unrecognized revenue. The 4x YoY jump reflects the new Meta $21B/6yr commitment plus Microsoft and OpenAI extensions. The metric to actually watch is conversion velocity: how quickly capacity comes online and customers ramp. If Meta recapitalizes its in-house compute and pulls back, this number compresses materially.

  • NVIDIA Q-over-Q data center revenue

    $62.3B (Q4 FY26)vs $57.0B (Q3 FY26)

    What this measures

    Data center segment revenue, sequential Q-over-Q. Captures Blackwell Ultra ramp and the start of Vera Rubin sample shipments. Beat or miss against the $62B run-rate sets the slope for H2 hyperscaler capex; a miss flattens Huang's-Law trajectory and re-rates the whole AI hardware narrative.

  • Open vs closed gap on SWE-Bench Pro (coding)

    Open +0.9vs Closed +6

    Threshold: Sustained open lead reshapes enterprise procurement

    What this measures

    Coding benchmark differential between top open-weight model (Kimi K2.6 at 58.6) and top closed model (GPT-5.4 at 57.7). Sustained open lead reshapes enterprise procurement because open weights run on-prem with predictable cost-per-token and no rate limits. The flip from closed +6 to open +0.9 is the inflection that makes self-hosting frontier-class AI a real procurement option this quarter.

  • Sovereign AI commitments (count / aggregate $)

    8 / $80B+vs 5 / $50B+

    What this measures

    Count of named national AI infrastructure programs and aggregate forward commitments. Current set: UAE Stargate (1 GW), Germany National DC Strategy, France IA program, Mistral-Sweden, GMI Japan, IndiaAI, UK AI Growth Zones aggregating $38.5B, plus the Saudi-PIF AI commitment. Reflects de-Westernization of compute provisioning and creates new merchant-silicon demand outside the hyperscaler axis.

  • PJM 2026/27 capacity auction price ($/MW-day)

    $329vs $29

    Threshold: 11x in 24 months — power is the new binding constraint

    What this measures

    Most recent PJM auction cleared at 11x the prior auction price, reflecting tightness in the capacity market driven by data-center load growth outpacing new generation build-out. Behind-the-meter generation is now mainstream; FERC compliance milestones in May-June will determine whether 2027 clearing prices repeat or normalize.

  • Time-to-power, busiest US markets (months)

    36-48vs 30-42

    What this measures

    Months from new-load interconnection request to energization in the most constrained US power markets (Northern Virginia, Phoenix, Dallas-Fort Worth, Columbus). Lengthening despite grid investment because demand is outpacing transmission build-out by 2-3x. The constraint is no longer chips, capital, or land — it is electricity delivery.

  • Cost-per-task, frontier reasoning model

    ~$0.05vs ~$0.08

    Falling cost expands workloads (Jevons), not contracts demand

    What this measures

    Median cost across the frontier-tier reasoning models for a benchmark complex task. The 38% drop reflects continued pricing pressure from open-weight competition and provider economies of scale. Falling cost expands the addressable workload set rather than contracting demand — this is the Jevons signature in AI inference.

  • Custom silicon share of incremental AI compute

    ~30%vs ~22%

    Threshold: >35% materially compresses merchant GPU pricing

    What this measures

    Approximate share of newly deployed AI compute capacity using custom silicon (TPU, Trainium, MTIA, Maia, Granite Rapids AI) versus merchant silicon (NVIDIA, AMD). The 30% threshold is structurally important: at this share, merchant GPU pricing power begins to compress as customers gain credible alternatives. Past 35% the compression is material and re-rates merchant gross margins.

Predictions

What we expect next.

6 predictions for the next 30-90 days, confidence 35%-80%.

Each prediction is falsifiable, time-bounded, and tied to a specific signal we will watch. Future issues score these hit, miss, partial, or pending and build a public track record.

Prediction 01

70%

confidence

Capital

At least one frontier lab announces a customer-funded compute commitment greater than 2 GW.

Deadline: By June 30, 2026

Trigger: Earnings cycle commentary on RPO from Oracle and AWS; announcements at Google I/O, Microsoft Build, AWS Summit.

Prediction 02

60%

confidence

Software

At least one Fortune 500 enterprise discloses an on-prem AI workload greater than $100M annual using open-weight models.

Deadline: By September 30, 2026

Trigger: Enterprise architecture announcements; bank, insurer, or pharma F500 first-mover; DeepSeek V4 reference deployment.

Prediction 03

80%

confidence

Capital

Aggregate 2026 hyperscaler capex revises upward by 10% or more from the $700B baseline.

Deadline: By October 31, 2026

Trigger: Q1 2026 earnings (Apr 29 - May 6) and Q2 2026 earnings cycle.

Prediction 04

70%

confidence

Networking

At least one major colocation or interconnect operator reports cross-connect or interconnect revenue growth outpacing compute capacity revenue growth for two consecutive quarters.

Deadline: By July 31, 2026

Trigger: Equinix Q1 (May 7) and Q2 (early August) earnings; broader colo and IX operator reporting.

Prediction 05

35%

confidence

Capital

At least one neocloud loses an anchor tenant or sees backlog growth turn negative quarter-over-quarter.

Deadline: By September 30, 2026

Trigger: Quarterly disclosures from CoreWeave, Nebius, Applied Digital.

Prediction 06

55%

confidence

Hardware

Custom silicon (TPU + Trainium + Maia + MTIA + Granite Rapids AI) reaches 35% of incremental AI compute share, up from ~30% today.

Deadline: By July 31, 2026

Trigger: TrendForce / SemiAnalysis quarterly mix breakdown; Q2 2026 hyperscaler earnings color on internal silicon vs merchant GPU mix.

Track record

Inaugural issue.

The track-record table populates from issue 02 onward, when the first batch of predictions can be scored. A hit rate of 65–75% is the target; above 80% means we are being too conservative; below 50% means the framework is wrong, not that we are unlucky.

Watchlist

On the radar this week.

5 catalysts to watch, starting Apr 29 - May 6.

Specific catalysts that would change the read materially. Watching these tells us whether the thesis is strengthening or weakening.

  • Apr 29 - May 6

    Q1 2026 hyperscaler earnings

    Capex direction signal that hits all four hyperscalers in eight days. Watch: aggregate revising higher, AI-segment margin disclosure, RPO commentary. Higher pushes the capex / revenue ratio past 6.0 (a lever threshold); lower is the first sign of ROI re-rating risk and tests prediction p3.

  • Late May 2026

    NVIDIA Q1 FY27 earnings

    First disclosure on Vera Rubin ramp velocity, HBM4 supply, and custom-silicon competitive pressure. Watch: data-center revenue vs the $62B run-rate, gross margin trend, customer-concentration commentary. A miss flattens the doubling slope; a beat resets the H2 hyperscaler capex tail.

  • May 2026

    Google I/O + Microsoft Build

    Frontier model and platform announcements that directly test prediction p1-2gw-customer-funded. Watch: any disclosed customer-funded compute commitment greater than 2 GW, RPO disclosures, agent-platform pricing. A 2 GW+ commitment scores p1 a hit before its June 30 deadline.

  • Through Q2 2026

    HBM4 memory supply ramp

    Validation status at SK Hynix, Samsung, and Micron is the binding constraint on Vera Rubin shipments. Watch: yield or qualification slips at any of the three. A slip compresses the H2 2026 hyperscaler capex tail materially; a clean ramp protects it and keeps Huang's slope intact.

  • April - June 2026

    FERC PJM compliance milestones

    Behind-the-meter generation materiality threshold takes effect, reshaping unit economics of large loads in the busiest US power market. Watch: FERC commentary on capacity attribution, ERCOT and MISO reactions. The outcome determines whether 2027 PJM clearing repeats the $329/MW-day or normalizes.

Companion reads

The rest of the spine.

The AI Stack Weekly is the cross-stack flywheel read. Pair it with the model-and-tree spine and the working framework to get the full picture.

Edits this issue

  • Inaugural issue. No revisions to the thesis. Future issues append entries here when evidence shifts a hypothesis.

About this brief

Compiled from public announcements, SEC filings, earnings transcripts, and official lab and vendor publications. Every quantitative claim is graded 1–5 on source quality. Claims graded 2 or below are flagged as noise. The thesis the brief defends is published separately and updated only when a hypothesis materially changes.

Authorship

Written by Brian Letort. Independent analysis. All sources cited are public. Not investment guidance.

Operate. Publish. Teach.