Rock the Code

Victor Rentea is a software engineer and architect, and an instructor. He's trained thousands of people in person at 150+ companies around the world. He's the highest-energy trainer and speaker I've come across.

You can find Victor's workshops at https://victorrentea.ro

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0:00 Intro
1:03 What Victor's training still teaches after AI
4:57 AI as a promotion: architect, product, or QA ninja
9:35 LGTM fatigue and multi-LLM code review
16:06 Victor's agentic setup: mouse-driven, voice-dictated
18:27 Software craftsmanship in the agentic era
22:25 Victor's training style and high energy
27:05 Handling contradictions in the room
31:47 Memorable trainings and the 80-senior room
36:12 How to start as a trainer/consultant
44:29 Juniors and skill erosion in the AI era
50:24 Over-engineering, hexagonal architecture, and AI
55:00 Tests, Gherkin, and acceptance-driven development
1:01:24 How Victor learns: newsletters and bright people
1:03:21 The JPoint failure that made Victor a better speaker
1:05:53 Advice for mid-senior devs riding the AI wave

Stephan Janssen is the founder of Devoxx, the largest chain of developer conferences in the world.

0:00 Intro
1:13 Vibe coding the Devoxx Companion app
5:30 Spec-driven development and the client-side validation bug
9:00 Token economics: spending €500 in one hour
15:00 Selfware and local models on Mac Studio
17:15 AI trends at Devoxx: MCP, agentic engineering, vibe coding's death
23:00 DHH's 180° and the developer renaissance
31:00 AI alignment and the Hugging Face agent incident
39:48 Skills still worth having as a senior engineer
44:28 What makes an amazing conference talk
49:17 Memorable Devoxx moments: hoverboards and proposals
55:20 Landing great speakers: bribing Joshua Bloch with Belgian beer
1:00:56 The future of Devoxx and DevRel in the age of AI agents
1:03:01 Robotics, local models, and what to learn next

Trisha Gee is a software engineer with more than 20 yeras of experience, a Java Champion and author of several books on Java and developer productivity. She is a frequent conference and keynote speaker and has held many roles around developer advocacy, training, consulting, and now managing an open-source project (the Aeron messaging protocol).

You can find Trisha's work at https://trishagee.com/

0:00 Intro
0:54 The Rise and Fall of Stack Overflow
5:05 Shortcuts vs. Fundamentals: Where to Draw the Line
15:03 What Actually Hasn't Changed in Software Engineering
21:04 Misusing the Word 'Refactor'
25:46 The Future of IDEs in an Agentic World
32:12 Teaching Developers to Read Code
37:58 Burnout: The 100% Capacity Problem
37:59 AI and the Joy of Coding
45:59 The Disappearing Junior Developer Pipeline
51:55 Pair Programming at LMAX: 6 Months vs. 10 Years
1:00:20 What Developer Advocacy Looks Like Now
1:07:18 Staying Relevant Without Panicking
1:18:09 Rebuilding a Website with Claude
1:24:04 Skill Atrophy and Using AI Without Losing Your Edge
1:31:19 Blogs and Resources Worth Reading
1:37:24 Are We Close to AI Best Practices?
1:40:03 Aeron, Determinism, and Agent Control Planes

Daniel Spiewak is known for spearheading Cats Effect, one of the major effect systems in the Scala ecosystem, and for leading Typelevel, a mini-ecosystem of libraries and tools for functional programming in Scala. He's held various senior engineering roles and is currently working for NVidia as a distinguished engineer.

0:00 Intro
1:00 Cats Effect 3.7 and Scala Native multithreading
6:30 Building async I/O from scratch on LLVM
9:30 The integrated runtime: replacing Java NIO on the JVM
13:30 Scala Native vs Rust: who wins?
17:00 Popularizing Scala Native with minimal resources
20:24 Scala in the agentic coding era
28:00 Where Scala's tooling falls short for AI agents
33:30 Resource lifecycle bugs: capture checking as the fix
37:38 Daniel's work at NVIDIA on autonomous vehicles
43:00 The Distinguished Engineer role explained
49:19 Becoming a Distinguished Engineer fast
54:18 Holding abstractions and bare metal simultaneously
1:03:00 Lessons from open source on people and patience
1:13:19 Starting a foundational OSS project: the steam engine analogy
1:20:00 The open frontier: DevOps and deployment orchestration in Scala
1:33:00 Unison's insight and what Scala should borrow

Dr. Venkat Subramaniam is an engineer, a professor at University of Houston, an author of more than 10 programming books, and a prolific speaker at technical conferences. He's trained tens of thousands of software engineers all across the world, consulted dozens of companies, and he's recognized as a Java Champion since 2013.

You can find Venkat's work at https://agiledeveloper.com/

0:00 Intro
1:07 AI as an amplifier: smart gets smarter
3:02 Why automated testing matters more with AI
7:38 The cost of failure and engineering discipline
12:50 Skin in the game: software's accountability gap
18:02 LLM-driven speed vs. engineering rigor
20:04 Local vs. global optimization in software orgs
26:21 LLMs vs. compilers: the cognitive decline fear
37:27 Gang of Four and SOLID: still relevant?
43:15 Design patterns as language deficiencies
46:32 Java's evolution: lambdas, value types, and the 6-month release cycle
55:02 invokeDynamic: the invisible JVM feature that changed everything
59:48 TypeScript, Elm, and the case for immutability
1:08:11 "There's got to be a better way"
1:19:10 TDD in practice: pair programming over training
1:26:41 Working for impact, not income
1:31:07 Venkat's approach to conference talks and live coding
1:38:01 The Kyiv keynote disaster
1:41:38 The art of elegant code
1:42:50 Immutability: human reasoning vs. system performance
1:47:51 "Help and seek help"

Magnus Madsen is an associate computer science professor at Aarhus University and the creator of the Flix programming language.

0:00 Intro
1:37 Flix fundamentals and design philosophy
3:57 Effect systems in the language vs. as a library
6:30 Effects as checked exceptions
10:57 Type inference and effect propagation
15:53 LLMs and Flix code generation
22:47 Datalog inside Flix
32:13 Research language vs. industry needs
37:03 Compiler tooling and VS Code integration
49:02 No warnings, only errors
51:03 Effect-aware package manager and supply chain attacks
54:59 Why the JVM, and WebAssembly futures
58:04 Flix-generated code outperforming Java
1:01:31 Java interop and effect system boundaries
1:07:48 Is programming language design still relevant in the AI age
1:09:35 Design regrets in Flix
1:13:09 Maintaining motivation across a decade of work

Richard Eisenberg is a language designer and compiler engineer for OCaml at Jane Street and a core contributor to the Haskell language. He focuses on static type systems and functional programming to make software more reliable, while maintaining ease of use and runtime efficiency. Richard has also taught various computer science topics to both university and high school students, and he holds a PhD from the University of Pennsylvania.

You can find Richard's work at https://richarde.dev/

0:00 Intro
0:56 Teaching CS to high school students
3:20 Turning down Microsoft for a teaching career
8:26 PhD, faculty life, and joining Jane Street
12:32 Algorithms and FP for high schoolers in the age of AI
17:08 How Richard uses LLMs day-to-day
22:29 Jane Street's internal AI experimentation
23:08 OCaml in the age of AI: open sourcing and error messages
29:31 Making illegal states unrepresentable: how far is too far
38:11 Formal verification and LLMs
42:08 Effect handlers in OCaml
44:03 Rust-style ownership and data race freedom in OxCaml
51:06 Why Jane Street chose OCaml
57:54 OCaml vs Haskell: purity, mutability, and physical equality
58:47 Onboarding engineers to OCaml at Jane Street
1:00:01 Hiring for fundamentals, not OCaml experience
1:07:07 Screening for good programming taste
1:10:47 Training vs hiring: the chicken-and-egg problem
1:15:31 Why OCaml hasn't gone mainstream
1:25:08 Dynamic languages: Python, JavaScript, and their place
1:28:15 Rust, C++, Scala: languages Richard finds interesting
1:33:08 Research at Jane Street: papers, peer review, and process
1:36:17 Contributing back to open source ecosystems
1:37:46 Dependent types in Haskell: motivation and the long road

Sam Newman is an engineer and consultant, specialized in service architecture. He's the author of the books Building Microservices and Monolith to Microservices, and has helped many companies make informed choices about their service architecture. His forthcoming book is Building Resilient Distributed Systems.

You can find Sam on his website https://samnewman.io/.

0:00 Intro
0:57 The distributed monolith trap
6:30 Structured programming fundamentals most devs skip
10:00 Why long-lived teams make better architecture decisions
13:33 Building Resilient Distributed Systems: the book
22:00 Three golden rules of distributed systems
22:11 The human side of resilience engineering
35:56 AI's impact on PR workflows and code verification
43:13 Why QAs are making a comeback
47:33 End-to-end testing in microservices architectures
58:21 Containerization, public cloud, and DevOps as microservices enablers
1:03:53 When Sam advises against microservices
1:09:38 Idempotency: retrofitting vs. designing upfront
1:15:21 Trunk-based development vs. the PR process

Daniel Spiewak is known for spearheading Cats Effect, one of the major effect systems in the Scala ecosystem, and for leading Typelevel, a mini-ecosystem of libraries and tools for functional programming in Scala. He's held various senior engineering roles and is currently working for NVidia as a distinguished engineer.

0:00 Intro
0:40 Cats Effect 3.7 and Scala Native multithreading
6:26 The integrated runtime: replacing Java NIO on the JVM
12:00 Scala Native vs the JVM for cloud-native workloads
14:00 Scala Native vs Rust: can it compete?
17:58 Popularizing Scala Native with minimal resources
21:04 Agentic coding and Scala's type system advantage
27:59 Where Scala's tooling falls short for AI agents
37:00 Resource lifecycle bugs that fool LLMs
37:44 Daniel's work at NVIDIA on autonomous vehicles
42:24 Capture checking and closing the linearity gap
44:43 What Distinguished Engineers actually do
49:35 How to reach IC7: breadth, communication, and humility
54:16 Holding abstraction and bare-metal performance together
58:00 Functional programming as a mental model for organizations
59:11 How open source shaped Daniel's engineering instincts
1:06:00 The steam engine lesson: technology needs context
1:12:00 Where Scala has room to grow: deployment and DevOps
1:19:57 Unison's big idea and what Scala can learn from it
1:27:06 Starting a foundational Scala project on a shoestring
1:32:42 Mill, Li Haoyi, and the build tool landscape

Simon Peyton Jones is a computer scientist in the true sense of the word, and the lead designer of the Haskell programming language and the GHC. He's a fellow of the Royal Society and the ACM and has won many awards (including the SIGPLAN award) for his contributions to programming language design. Simon is currently working for Epic Games with the CEO Tim Sweeney on Verse, a programming language that brings functional programming to video games.

You can find Simon at https://simon.peytonjones.org/

0:00 Intro
1:42 Origins of type classes in Haskell
7:01 Higher-kinded type variables and the monad surprise
12:31 Tasteful abstractions: when complexity is worth it
18:46 GADTs, higher-rank polymorphism, and OOP connections
23:24 Static vs. dynamic typing: the real case for types
27:18 Laziness, purity, and the IO monad
32:46 What mainstream languages should steal from Haskell
39:41 Subtyping vs. parametric polymorphism
44:31 Verse: types as functions and expressions as patterns
52:32 Verse's mathematical ambitions and Tim Sweeney
57:30 LLM-generated code and the limits of verification
1:04:01 Property-based testing as practical verification
1:08:20 Teaching CS fundamentals to children
1:14:39 Juniors, seniors, and AI in the workforce
1:23:07 Immutability changes everything