Developer & Web Technologies Focus: Developer Productivity & Generative AI Socials: linktr.ee/daniel_sogl 2 Code smarter, not harder How AI coding tools boost productivity — and where they don't
…used an AI coding assistant this morning? 2. …let an AI agent open a PR for you this week? 3. …shipped AI-generated code you didn't fully understand? 3 Code smarter, not harder How AI coding tools boost productivity — and where they don't
actually stand (May 2026) Adoption is solved. Impact is not. Act 2 — Smart along the SDLC Where AI really helps — and where it quietly hurts Act 3 — From Vibes to Specs The biggest leverage upgrade of 2026 Act 4 — From Local to Cloud The PR is the new interface Act 5 — Roles are changing — all of them Engineer · QA · PM · Designer · SRE 4 Code smarter, not harder How AI coding tools boost productivity — and where they don't
developers use or plan to use AI tools Stack Overflow Developer Survey 2025 · N=49,000 90% use AI at work JetBrains AI Pulse Apr 2026 · N=11,000 73% use AI daily — up from 41% in 2025 Pragmatic Engineer Feb 2026 · N=15,000 22% already use coding agents JetBrains AI Pulse Apr 2026 Four surveys. ~100,000 developers. The adoption question is closed. The question now: did it make us smarter? 6 Code smarter, not harder How AI coding tools boost productivity — and where they don't
actually trust them — down 11 points YoY We use it. We don't trust it. We use it anyway. 66% spend more time fixing "almost-right" AI code — and it's their #1 frustration. SOURCE — STACK OVERFLOW DEVELOPER SURVEY 2025 · 49,000 RESPONDENTS 7 Code smarter, not harder How AI coding tools boost productivity — and where they don't
OSS devs slower with AI. They felt 20% faster. 16 devs · 246 tasks · mature repos → FEBRUARY 2026 UPDATE −18% Same devs, retested. New cohort: −4% (CI: −15 to +9%). 57 devs · 143 repos · 800+ tasks METR, in their own words: "An unreliable signal of current productivity effects." 30–50% of developers refused tasks they'd have to do without AI. Selection bias killed the RCT design. SOURCE — METR.ORG · 2025-07-10 & 2026-02-24 · ARXIV:2507.09089 8 Code smarter, not harder How AI coding tools boost productivity — and where they don't
that of an amplifier. It magnifies the strengths of high-performing organisations and the dysfunctions of struggling ones." Strong teams get stronger. Struggling teams get worse — faster. +39% first-year ROI ~8-month payback 5 → 6% change-failure rate "instability tax" ↑ Throughput ↓ Stability trade-off — not optional SOURCES — DORA 2025 STATE OF AI · DORA 2026 ROI OF AI-ASSISTED SOFTWARE DEVELOPMENT 9 Code smarter, not harder How AI coding tools boost productivity — and where they don't
2. Design Architecture · ADRs 3. Implementation Greenfield · Legacy 4. Test Coverage · Mutation 5. Review AI as reviewer 6. Docs Drafting · Maintaining 7. Maintenance Refactor · Legacy 8. Ops Incident · Debug One hero number. One caveat. One smart move. 11 Code smarter, not harder How AI coding tools boost productivity — and where they don't
NUMBER 31% domain-hallucination rate in real-world LLM use up to 60% in complex domains SMART MOVE Persona prompts + domain glossary file. Treat the LLM like a new hire. Validated finding: LLMs can generate and assess user stories at scale — but only with explicit domain context. Zero-shot output is generic theatre. Sources — arXiv:2504.00513 (UStAI) · arXiv:2507.15157 · SQ Magazine LLM Hallucination Stats 2025 12 Code smarter, not harder How AI coding tools boost productivity — and where they don't
980 ADRs across 109 GitHub repos analyzed by LLMs violations detected — cross-decision reasoning weak SMART MOVE Feed your own ADR history into the context window. Path-dependency is everything in architecture. LLM as sounding board: excellent for pattern matching, options analysis, trade-off enumeration. Weak at "why did we already decide against this". Sources — arXiv:2602.07609 · arXiv:2604.03826 (EASE 2026) · arXiv:2504.08207 (DRAFT) 13 Code smarter, not harder How AI coding tools boost productivity — and where they don't
SIMPLE TASKS 35–40% productivity gain new projects · clean slate · isolated tasks COMPLEX LEGACY CODE ≤10% gain — or negative existing systems · the 90% of real work AI is up to 4× more productive on greenfield than on code you maintain. Most of us live on the right side of this slide. Smart move: spec-driven + small batches. Big legacy refactors with AI are an anti-pattern. We come back to this in Act 3. Sources — Stanford SEP (in DORA 2026) · METR 2025 RCT 14 Code smarter, not harder How AI coding tools boost productivity — and where they don't
HERO NUMBERS 30 → 90% line coverage in 5 min → zero bugs found tests match the code that already exists FIELD NOTE "We hit 99% coverage with AI" — and zero bugs found. The AI tested what the code does, not what it should do. Smart move: BDD-first. Tests assert the requirement, not the implementation. AI proves business intent. You review the technical "how". Sources — eferro Nov 2025 · Nimble Approach Dec 2025 · field experience 15 Code smarter, not harder How AI coding tools boost productivity — and where they don't
49% CodeRabbit precision · 46% runtime-bug detection vs. <20% for classic static analyzers TURNAROUND 9.6 → 2.4 days Duolingo PR median · −67% · +70% PR volume FIELD NOTE AI as pre-reviewer: catches the obvious, frees humans for taste & architecture. The catch: AI-generated code produces 1.7× more issues than human code (CodeRabbit, N=470 OSS PRs). → More AI authoring ⇒ more AI reviewing. Smart move: AI catches first pass, you decide what ships. Sources — CodeRabbit Martian Benchmark 2025 · CodeRabbit "State of AI vs Human Code" Dec 2025 · GitHub Docs 16 Code smarter, not harder How AI coding tools boost productivity — and where they don't
using AI as primary doc tool nearly doubled in one year REALITY CHECK Synthetic benchmarks: 84–89% correct. Real-world classes: 25–34% correct. Smart move: docs as versioned spec artefacts, not afterthought. AI drafts, humans validate against intent — same loop as code. Sources — State of Docs 2026 · arXiv:2510.26130 (Real-world Class-Level Code Doc) 17 Code smarter, not harder How AI coding tools boost productivity — and where they don't
code-clone blocks YoY ≥ 5-line duplicates 25 → <10% refactored-code share of all changes cut by 60% since 2021 5.5 → 7.9% code churn within 2 weeks code revised right after merge FIELD NOTE · WPF → WEB MIGRATIONS Run the agent blind on a legacy migration and it translates the old debt into the new architecture — same anti-patterns, new stack. Smart move: name the weaknesses first. Anti-patterns in instructions · domain rules in skills · self- healing hooks to catch regressions. Proven across multiple client engagements — WPF desktop → modern web apps. Source — GitClear AI Copilot Code Quality Report 2025 · 211M changed lines · field experience 18 Code smarter, not harder How AI coding tools boost productivity — and where they don't
NUMBERS −40 to −70% MTTR in AI-augmented pilot teams 13,000 h engineering hours saved · Uber Genie Co-Pilot since Sep 2023 CAVEAT +30% manual toil despite AI investment. Tool-sprawl is the new bottleneck. Smart move: fix your alerting before adding AI on top. AIOps amplifies noise just as well as signal. Sources — Rootly 2025 State of DevOps · Uber Engineering · Digital Applied 2026 · incident.io 19 Code smarter, not harder How AI coding tools boost productivity — and where they don't
Greenfield implementation Code review (pre-pass) Incident triage & correlation User-story / doc drafting Test scaffolding (then mutate) LOW / NEGATIVE LEVERAGE Complex legacy refactors Cross-decision architecture Domain-heavy requirements (no glossary) "Vibe maintenance" AIOps on top of broken alerting Smart isn't "more AI". Smart is AI in the right place — and knowing when to keep it out. 20 Code smarter, not harder How AI coding tools boost productivity — and where they don't
and where most of us are stuck Specs Explicit intent. Repeatable. Team- shareable. Skills Reusable agent capabilities. Composable. Agents Plan, execute, iterate. Autonomously. Most teams ship from Vibes. The wins are in Specs. Vibes Intuitive, conversational. Fast — until it isn't. Source — Red Hat Developer · "Vibes, specs, skills, and agents" · March 2026 22 Code smarter, not harder How AI coding tools boost productivity — and where they don't
for a reason. A what. A why. The agent handles the syntax. The agent knows the API. It doesn't know your customer, your domain, or the problem you're actually solving. That part is on you — and it's where your value as an engineer now lives. WHAT STILL MATTERS · WHAT DOESN'T Understanding the customer's problem Defining behaviour & constraints The speedup comes from alignment — not from faster typing. Memorising framework APIs Knowing the syntax cold Source — Microsoft Developer Blog · GitHub Spec Kit · Sept 2025 23 Code smarter, not harder How AI coding tools boost productivity — and where they don't
STEP ZERO — BEFORE ANY CODE Who is this for, and what problem does it solve? If you can't answer that in one sentence, no agent — local or cloud — will save the work. A spec is just this answer, written down in a form the agent can act on. Spec Kit, Kiro & Co. automate steps 1–4. They cannot do step zero. THEN — AND ONLY THEN — THE PIPELINE 01 Specify the what 02 Plan the how 03 Tasks the steps 04 Implement agent → PR Source — github/spec-kit · Kiro Specs · Tessl 24 Code smarter, not harder How AI coding tools boost productivity — and where they don't
Spec-first Persistent context for every session. No automation. Where most teams start. AGENTS.md CLAUDE.md .cursorrules LEVEL 2 — SWEET SPOT Spec-anchored Spec evolves with code. Slash commands, checkpoints, cross-artefact consistency. GitHub Spec Kit ~100k★ · 30+ agents supported Kiro (AWS) Agentic IDE · EARS notation LEVEL 3 Spec-as-source Humans only edit specs — never generated code. Generated files marked DO NOT EDIT . Tessl Private beta · spec is the source Most teams in May 2026 sit between Level 1 and Level 2. If you take one thing from this talk: write an AGENTS.md tonight. 25 Code smarter, not harder How AI coding tools boost productivity — and where they don't
· co- creator of Django: "I won't commit code I couldn't explain to someone else." → Forces understanding. Kills hallucinated dependencies. Catches silent bugs. Addy Osmani · Google: Beware "house of cards code". → Fragile AI output that collapses under scrutiny. Specs in workflows prevent it. 26 Code smarter, not harder How AI coding tools boost productivity — and where they don't
2025 / 26 Async Cloud Agents in your PR queue THE INTERFACE TO AI IS NO LONGER the cursor → it's the pull request 2022 Autocomplete tab in the IDE 2023 Chat side panel 2024 Agents inside the IDE 28 Code smarter, not harder How AI coding tools boost productivity — and where they don't
at Goldman Sachs, Citi, Nubank, Dell. Valuation $10.2B → $25B in talks (Apr 2026). OpenAI Codex Cloud 4M+ weekly developers (Apr 2026 · OpenAI announcement). 10× growth since Aug 2025. GitHub Copilot Coding Agent Assign an issue → get a PR. ~1.2M PRs/month. CODEOWNERS, branch protection apply. Cursor 3 ("Glass") April 2026. Parallel agents in worktrees + cloud sandboxes. 30% of Cursor's own merged PRs from background agents. Also in the field: Claude Code (via GitHub Action) · Google Jules · Sourcegraph Amp · Tembo. Sources — Vendor announcements · OpenAI 21.4.2026 · Bloomberg 23.4.2026 · InfoQ 2.4.2026 29 Code smarter, not harder How AI coding tools boost productivity — and where they don't
Editor-in-Chief OLD LOOP open IDE · write · test · commit · push · PR · wait for review NEW LOOP write spec · assign agent · do other work · agent opens PR · you review · iterate · merge 31 Code smarter, not harder How AI coding tools boost productivity — and where they don't
traditional PMs. ~25 engineers, 1 head of product. PostHog Same playbook. Published the playbook. Vercel "Code-last" philosophy. Outcomes > commits. Stripe Early pioneer. High-ownership engineering. Shopify Product engineers shipping product, not features. incident.io JD: "outcomes & impact > exact implementation" "In an AI-first era, product engineering is more important than ever. Dare I say — it's basically the only thing left." — Lee Robinson · Vercel / Cursor 33 Code smarter, not harder How AI coding tools boost productivity — and where they don't
· NOV 2025 AGE 22–25 −20% software-developer employment since late-2022 peak AGE 35–49 · SAME ROLES +6–9% in the same AI-exposed roles AI rewards existing expertise. It punishes "junior implementer". Routine implementation evaporates first. The question this opens: If junior pipeline collapses, who's the senior in 5 years? Source — Brynjolfsson, Chandar, Chen · Stanford Digital Economy Lab · ADP payroll data · 3.5–5M workers 34 Code smarter, not harder How AI coding tools boost productivity — and where they don't
Quality Owner 58% of enterprises upskill QA in AI. QA-engineer roles +17% YoY vs. devs +9%. Test-author → quality strategist. PM → Builder Linear: no PMs. PMs that ship prototype to stakeholder review in <10 minutes using Claude Code & v0. Designer → Frontend Author v0, Galileo V3, paper.design — Figma → production- ready frontend code. Designer's deliverable becomes a PR. SRE → Platform Multiplier DORA: 90% of orgs have a platform · 76% a dedicated team. Platform quality decides whether AI helps or hurts. Every role on the team is moving up the abstraction stack. The deliverable changes — but the seat in the room stays human. Sources — World Quality Report 2025 · Lenny on Linear · Productside · DORA 2025 35 Code smarter, not harder How AI coding tools boost productivity — and where they don't
risk isn't being replaced by AI. It's being out- competed by someone on your team who uses it smarter. 36 Code smarter, not harder How AI coding tools boost productivity — and where they don't
real spec A CLAUDE.md , AGENTS.md , or .cursorrules for your most active repo. Treat it like onboarding for a new hire. 2 Pick one SDLC phase to optimise Not "use more AI everywhere". Pick test, or review, or incident triage — and measure the change for 2 weeks. 3 Run a cloud agent on one real backlog item Pick a Copilot / Codex / Devin / Jules task. Let it open the PR. Review like a senior would. Notice what you'd actually ship. 38 Code smarter, not harder How AI coding tools boost productivity — and where they don't
place, at the right time, and knowing when not to use it at all. 39 Code smarter, not harder How AI coding tools boost productivity — and where they don't