Engineering & QA

Engineering & QA is responsible for everything we build and the quality of what we ship. Engineers design, implement and maintain the software; QA engineers own test strategy, coverage and release confidence. Both disciplines work shoulder-to-shoulder on every project — quality is not a handoff at the end, it’s a shared standard throughout.

The function is led by Anand (Partner, Engineering & Technology).

Before reading the ladder, understand the Career Philosophy — specifically the concepts of Impact and Leverage that underpin every level below.

Software Engineering Ladder

L0 — Intern

Impact: individual task level

Works on well-scoped, short-term tasks with close supervision
Learns the codebase, tooling, and how professional software development actually works
Asks questions freely — curiosity and honesty about what you don’t know is expected at this level
Produces work that is reviewed heavily; that’s the point, not a reflection of failure
An internship at Arillus is about discovering whether engineering is your function and whether Arillus is your place

L1 — Associate Software Engineer

Impact: individual / project level

Delivers well-defined tasks with guidance from a senior
Writes working code that passes review; reviews frequently catch significant issues
Learns the codebase, tooling, and team conventions — asks for help early rather than staying stuck
Treats code review feedback as learning, not criticism

L2 — Software Engineer

Impact: individual / project level

Delivers features end-to-end from a written story — including tests, edge cases, and error handling — with reviews catching only minor issues
Debugs own problems methodically before escalating
Estimates own work with reasonable accuracy; flags scope changes early
Begins reviewing L1 code and giving useful, specific feedback
Communicates progress without needing to be chased

L3 — Senior Software Engineer

Impact: multiple projects

Owns a module or workstream end-to-end: design, implementation, testing and handover
Designs solutions before implementing — considers edge cases, performance and security from the start
Breaks down ambiguous requirements into concrete technical tasks
Reviews code as a routine, not an exception; actively mentors L1–L2 engineers
Can Tech Lead a standard project: runs technical standups, unblocks teammates, owns the technical relationship with the Product Lead and client
Handles straightforward technical conversations with clients directly
Raises concerns about scope, feasibility or quality early

Engineers at L3 and above are capable of being Group Leads — taking on people leverage alongside their technical work. See Career Philosophy and Groups.

L4 — Staff Software Engineer

Impact: multiple projects simultaneously

Tech-leads complex or large projects; owns architecture decisions within them
Acts as fractional Architect/Reviewer for projects led by L3s — reviews approach at kickoff, checks in at milestones
Handles difficult technical client conversations independently: pushback, trade-offs, hard constraints
Raises the team’s engineering bar through documented standards and patterns, not just personal output
Identifies systemic problems across projects and drives solutions, not just workarounds

L5 — Senior Staff Software Engineer

Impact: company level

Provides technical oversight across the firm’s entire portfolio of active projects
Escalation point for the firm’s hardest technical problems
Owns cross-project decisions: technology choices, reusable components, shared libraries, engineering standards
Measured by the capability and quality of engineering output across the whole organisation — not just their own work

L6 — Principal Software Engineer

Impact: company level, exceptional

Owns the engineering practice itself: how Arillus builds software, stack decisions that span all clients, the firm’s technical reputation
Trusted by clients and partners as the highest technical authority in the firm
Rare. This level exists when the firm needs it, not on a fixed timeline.

QA Ladder

L1 — Associate QA Engineer

Impact: individual / project level

Executes test plans written by others accurately and thoroughly
Reports defects with clear steps to reproduce, expected vs. actual behaviour, and environment details
Learns the project’s domain, testing tools, and team conventions
Asks for help early when a test case is ambiguous or a defect is hard to reproduce

L2 — QA Engineer

Impact: individual / project level

Independently owns testing for a small project: writes test plans from user stories, tracks coverage, manages regression
Identifies gaps in requirements and raises them before development begins
Communicates defect status and release confidence without being prompted

L3 — Senior QA Engineer

Impact: multiple projects

Defines test strategy from project kickoff: what to automate, what to manual test, where the risk sits
Reviews L1–L2 test plans and gives specific, constructive feedback
Leads automation efforts and sets the standard for how the project tests
Handles quality conversations with clients directly

L4 — QA Lead

Impact: multiple projects / company

Sets quality standards across multiple projects and audits adherence
Reviews test approaches at project kickoff; spot-checks coverage and quality at milestones
Mentors L1–L2 QA engineers; owns their growth
Identifies systemic quality issues across projects and drives process improvements firm-wide